Draft2 Finalized Project Covac

8/14/2019 Draft2 Finalized Project Covac

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It is been declassified by The Internet Guild and members of the Archiver realm.

It is copyrighted by nobody and is released under public domain and all Dishes are copyrighted by theirrespectful owners.

Covac stans for Communications Online-Network Virtual Amplification Communications

This file is been made public by the Secret Archivers and Infowarriors.

This information is also by an autistic person who has been around technology since he was very little.


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The type of Equipment, supplies, and other things that are needed in order to build the systemChapter I.

My plans are to build Biquad antennas since it creates a wifi style satellite, each and every satellitedoesn't have to meet the guidelines of this handbook but the point of this is to make long range wifiextenders to meet people in rural areas and for long range transmissions, not to mention higher qualitytransmissions in close range areas. It is not illegal to use a Biquad Antenna and having a backupInternet communications system is also not illegal and buying the parts for this is as well not illegal andis recommended during natural disasters and cut off communications points. This specific chapter willexplain what equipment, supplies, and other things that need to be bought or made in order to set up the

system.

These are the parts and ingredients you will need for the system unit that connects to other peers.

This is one way to build the Biquad Antenna and Covaccommunication system(Source martybugs.net) A.

Use the following bits and pieces:1x 123x123mm square section of blank PCB

1 x 50mm length of 1/2" copper pipe

1 x short length of CNT-400 or LMR-400 low loss coax (~300mm long)

1 x 250mm of 2.5mm2 copper wire (approx 1.5mm diameter)

1 x N connector

1x Dish network Satellite Dish

Note: that you don't have to use blank PCB for the reflector. You can use any material that's electricallyconductive, can be electrically connected to the coax braid, and will reflect microwaves (ie, any metalplate will do fine).I've also heard of people using CDROM as the reflector, as the foil on it will certainly reflectmicrowaves.

Background of technician involved:

I've done quite a bit of experimentation and testing with various home made dipoles for 24dBi Coniferdishes, and have managed to increase the performance of the dish.


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Trevor Marshall has a webpage with information about using a biquad as a feed on a Primestar satellitedish, with very good results. I decided to try using a biquad as a feed on a 24dBi Conifer dish, to see ifI could improve the performance of it of the dish.

Note that the photos on Trevor Marshall's webpage do not clearly show the construction of the biquad -particularly the way in which the quad is attached to the coax. Numerous people (including myself)

have constructed biquads incorrectly, based on his photos, and found that they perform very poorly.Use the photos of my biquad below, and refer to the websites listed in the references section at thebottom of this page for more information on the correct construction of the biquad.

Reflector:

Cut a square piece of blank printed circuit board, 123x123mm.

Note that Trevor Marshall (Go to the Trevor Marshall section to read his work) recommends a size of123x123mm if using the biquad as a stand-alone antenna, while 110x110 is optimal if using it as a feedfor a large dish.He also recommends attaching some lips to two sides of the reflector, to reduce radiation from the rearlobes.

Use some steel wool to remove any tarnish and polish it up. Cleaning the copper in this way will makeit easier to solder.

blank printed circuit board

Cut a 50mm section of copper pipe, and file both ends smooth. Using some sandpaper and/or somefiles, polish up the copper pipe (including the inside of the copper pipe, to ensure a good connectionwith the coax braid).


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the dimensions of the copper pipe (Enlarged to show texture and for larger screens)

Cut a notch into one end of the copper pipe, removing approx 2mm from half the circumference.

A short section of copper pipe, notched at one end (Enlarged to show texture and for larger screens)

Drill a hole in the centre of the blank PCB so that the copper pipe is a tight fit in the hole. I found areamer to be very useful for enlarging the hole to the correct size.


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making a hole in the center (Enlarged to show texture and for larger screens)

Insert the copper pipe into the hole, with the notched end on the copper side of the blank PCB. Thecopper pipe should be protruding approx 16mm through the hole, measured on the copper side of thePCB.

Insert the copper pipe into the reflector (Enlarged to show texture and for larger screens)

Solder the copper pipe to the PCB, to ensure a good physical and electrical connection.

The next Image is on the next page.


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solder the copper pipe to the PCB (Enlarged to show texture and for larger screens)

Quite a bit of heat is needed, due to the thickness of the copper pipe, and an electrical soldering ironprobably won't be able to deliver sufficent heat. I found a small gas torch works quite well.

Making the Element:

The element is made from a length of copper wire, bent into the appropriate shape.

Note that the length of each "side" should be as close to 30.5mm as possible (measured from the centreof the copper wire to the centre of the copper wire), which is a quarter of a wavelength at 2.4GHz


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the shape and dimensions of the element (Enlarged to show texture and for larger screens)

I had some offcuts of electrical power cable lying around, and found that 2.5mm2 power cable had adiameter of approx 1.6mm - a little bigger than the 1.2mm that Trevor Marshall specifies, but didn'tthink it would make a significant difference to the performance of the biquad.

recycling power cable offcuts (Enlarged to show texture and for larger screens)

Remove the insulation, measure and cut a 244mm length the copper wire, and straighten it as best asyou can.


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straighten the wire (Enlarged to show texture and for larger screens)

Measure the mid-point of the wire, and make a 90 degree bend. The bend should be quite sharp andpronounced.

90 degree bend (Enlarged to show texture and for larger screens)

Measure the midpoints of each half, and make two more 90 degree bends in the wire, so that it lookslike that shown in the photo below.


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make it symetrical... (Enlarged to show texture and for larger screens)Clean up all your bends, and ensure each side of the element is as straight as possible, and as close to

30.5mm as possible.Note that you may need to trim a small amount off each end of the wire to achieve this.

Assembly:

The element must now be attached to the reflector. Note that only the two "ends" of the copper wire areto be attached to the copper pipe - the centre of the copper wire must not touch the copper pipe (hencethe notch which was cut into the end of the copper pipe.

The copper wire element should be approximately 15mm away from the reflector. Testing antennaperformance while varying the spacing between the copper wire element and the rear reflector indicatesthat a spacing of approx 15mm provides the lowest SWR (test results available

http://forum.wirelessnederland.nl/viewtopic.php?t=918&postorder=asc&start=45but is not in English).
http://forum.wirelessnederland.nl/viewtopic.php?t=918&postorder=asc&start=45http://forum.wirelessnederland.nl/viewtopic.php?t=918&postorder=asc&start=45http://forum.wirelessnederland.nl/viewtopic.php?t=918&postorder=asc&start=45


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the element soldered onto the copper pipe (Enlarged to show texture and for larger screens)

Strip approx 30mm of the outer sheath from the end of the coax.

strip the outer sheath (Enlarged to show texture and for larger screens)

Fold the braid back over the outer sheath, and trim the centre conductor, so that about 4mm isprotruding.


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fold the braid back, trim the centre conductor (Enlarged to show texture and for larger screens)

Insert the braid into the copper pipe, so that the end of the centre conductor lines up with the extremeend of the copper pipe, and solder the centre of the element to it, ensuring the centre of the element isnot in contact with the copper pipe. Refer to some of the additional photos below for details.

solder the centre conductor to the element (Enlarged to show texture and for larger screens)


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another view (Enlarged to show texture and for larger screens)

Note that the feed between the rear reflector and the biquad element needs to be shielded. Using coaxto feed the biquad element directly, and positioning the coax inside the copper tube achieves this.Use of bare conductors as a feed between the reflector and biquad element results in a radiating feed(such as the one in the image on the next page), which will have a detrimental effect on the biquad'sperformance.

I used a coax crimper to crimp the end of the copper pipe onto the coax. This ensures that the coaxwould not move inside the copper pipe.


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(Enlarged to show texture and for larger screens)


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the copper pipe crimped onto the coax (Enlarged to show texture and for larger screens)

the completed biquad (Enlarged to show texture and for larger screens)

Now terminate the other end of the coax with an N connector.

If desired, you can add spacers at each end of the element, to ensure the element doesn't move inrelation to the reflector. Refer to the double biquad section of this document for more details on making


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spacers to support the element.

If you intend to mount the biquad outside, I'd recommend you place it into a weather-proof enclosure,to prevent corrosion, and to prevent water ingress into the coax.Numerous people have used small tuppaware containers successfully.

This can be achieved by drilling a hole in one side of the container, and pass the coax tail through thehole, leaving the biquad itself inside the container. Seal up the hole for the coax with some silicone, andyour biquad should be protected against the elements.

another view of the completed biquad (Enlarged to show texture and for larger screens)

Testing:

Some very rough initial testing using the biquad as a feed on a 24dBi Conifer dish looks verypromising, with the signal strength being at least as as good as my home made (You can go to theModifying Conifer Antennas for Wireless Networking section for this) Conifer dipole (I was holdingthe biquad at approximately the focal point of the dish, and hadn't even removed the Conifer dipole).

I also managed to get a marginal link to a 180 degree waveguide on an access point 10km away, usingonly the biquad by itself, connected to a 30mW RoamAbout wireless card.

Some more detailed testing (you can go to the Antenna Comparison Testing section for this) withmultiple antennas, including the biquad shown above, indicates the biquad has a gain of approx 11-


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12dBi.

A friend has access to some antenna test equipment, and performed some tests on the biquad featuredon this page.The azimuth plot (ie, radiation pattern) of the biquad is shown below, and shows a 3dB beamwidth ofabout 50 degrees.

azimuth plot of the biquad

Variations:

VariationsA number of people have suggested the spacing between the element and the rear reflector should be a


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1/4 wavelength (ie, 30.5mm) instead of 15mm. However, test results (such ashttp://forum.wirelessnederland.nl/viewtopic.php?t=918&postorder=asc&start=45warning notEnglish!) indicate the SWR of the biquad is minimised when the spacing is about 15-17mm. Increasingthe spacing to 30.5mm increases the SWR significantly, thus reducing the efficiency of the biquad.

For a higher-gain variation of the biquad that's virtually just as easy to build, have a look at the Double

Biquad Antenna Section in this document.

Usage:

When using a biquad to establish a link to another wireless device, you should ensure the polarisationof the biquad is the same as the antenna you are connecting to. Similarily, if establishing a link withtwo biquads, ensure they are both oriented for the same polarisation.Failing to match the polarisation will result in significant signal loss.

vertically polarised horizontally polarised(Enlarged to show texture and for larger screens)

Changing the polarisation is just a matter of rotating the entire biquad antenna by 90 degrees.

The biquad antenna is not particularly directional, but has a fairly wide beamwidth.The 3dB beamwidth for a biquad (without side lips) is typically about 40-50 degrees, thus making itideal for any applications where you want fairly wide coverage.

The relatively wide beamwidth also makes a biquad very suitable for war-driving and stumbling,allowing you to pick up signals without having to align the antenna directly with the signal source.

While a directional antenna, such as a Conifer dish (See the Modifying Conifer Antennas for WirelessNetworking Section in this document) (3dB beamwidth of a 24dBi Conifer dish is approx 7 degrees), isbetter suited for point-to-point links, the narrow beamwidth of a Conifer dish requires more precisionwhen aligning the antennas (the narrower the beamwidth, the less susceptible it will be to interferancefrom other sources). An antenna with a wider beamwidth, such as a biquad, doesn't require the sameprecision for alignment, thus making it easier to get a link working.
http://forum.wirelessnederland.nl/viewtopic.php?t=918&postorder=asc&start=45http://forum.wirelessnederland.nl/viewtopic.php?t=918&postorder=asc&start=45http://forum.wirelessnederland.nl/viewtopic.php?t=918&postorder=asc&start=45


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From the coordinator of this document I recommend you buy a Kid instead of doing work to get all theparts especially if those parts are rare, but if these Kits ever get banned from being sold and don't showup on any kind of market then buy all the parts separately in cases of censorship or control)

Kits:

If you're one of those people who may not have all the tools required for building a biquad antennafrom scratch, or you don't want to shop around for all the parts required, you can buy a DIY kitcontaining all components from WarDrivingWorld (http://wardrivingworld.com/ It's an ebay store).

In November 2006, WarDrivingWorld sent me one of their DIY biquad kits to review. The kit containsall the pre-cut and pre-drilled parts required to build a biquad antenna.For more infomation on this kit, including antenna comparision test results, read my Review of theWarDrivingWorld DIY Biquad Kit (See section Review of WarDrivingWorld DIY Biquad Kit).

Online References (Which are not included in the document):

http://www.saunalahti.fi/elepal/antenna4.htmlhttp://reseaucitoyen.be/?BiQuadhttp://www.geocities.com/lincomatic/homebrewant.html#biquad

Double Biquad Antenna B.

This page contains details on building a double biquad antenna with approx 13dBi gain.

Background on Same Technician:

Having experimented with a number of biquad antennas (construction details on last section), I havefound them to be relatively easy to construct, reliable, and good performers, with about 11 dBi gain.

A number of websites showed a variation of the biquad, with the reflector being double the size, andwith the element having twice as many sections.

I decided to make a double biquad, to see how the gain compared to that of a biquad.

Construction:

I made a double biquad using exactly the same construction techniques as described on the last section,except the rear reflector is 110x220mm, and the element is double the size.
http://wardrivingworld.com/http://www.saunalahti.fi/elepal/antenna4.htmlhttp://reseaucitoyen.be/?BiQuadhttp://www.geocities.com/lincomatic/homebrewant.html#biquadhttp://wardrivingworld.com/http://www.saunalahti.fi/elepal/antenna4.htmlhttp://reseaucitoyen.be/?BiQuadhttp://www.geocities.com/lincomatic/homebrewant.html#biquad


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double biquad (Enlarged to show texture and for larger screens)

Note that the element wires do not touch where they cross over, but are separated with a gap of approx1-2mm.

To provide some more robustness, and to ensure the element doesn't move, I added some spaces at eachend of the element.The spacers are made from a small section cut from a hollow reticulation riser, and attached to thereflector and element using a small wire tie. Measure and cut the spacers to be 14.5mm long, as thisshould result in the element being the correct 15mm from the reflector.


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parts required for the spacers (Enlarged to show texture and for larger screens)

Drill two small holes in the reflector, in line with each end of the element. The holes must be largeenough to allow the wire tie to pass through them.

two holes in the reflector for the cable tie (Enlarged to show texture and for larger screens)

The spacers are attached by passing the wire tie through one of the holes in the reflector, through thetube, looped around the element, and then passed through the tube again, and through the other hole inthe reflector.


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spacer installed (Enlarged to show texture and for larger screens)

The spacers will ensure the posititioning of the element relative to the reflector will not change, andalso means the antenna is less likely to be damaged while in transit or while being handled.

detail of spacer (Enlarged to show texture and for larger screens)


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completed double biquad (Enlarged to show texture and for larger screens)

Testing:

To determine the difference in gain between a biquad and the double biquad, some tests wereperformed, with the signal, noise and SNR recorded.

antenna SNR(dB)

signal

(dBm)noise

(dBm)

biquad 43 -58 -101

double

biquad

45 -56 -101

The test results indicate that the gain of the double biquad is approx 2dBi higher than that of thebiquad, which is a significant improvement (as 3dBi is a doubling of signal).

As the biquad has a gain of 11-12dBi, this means the double biquad has a gain of 13-14dBi, so it's apretty good performer for something that's relatively easy to build.

These results are similar to those obtained by other people who have made double biquads.


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References:

last sectionPhotos of a Double BiQuadDouble Double Quad

Modifying Conifer Antennas for Wireless Networking C.

This page details a method for constructing a new dipole for a Conifer dish, resulting in improvedperformance over the more common dipole modification.

Conifer (ex Galaxy) Antennas:

The antennas we're using are made by Conifer (now known by the name of their parent company,Andrew Corporation ref. www.andrew.com), and were used in Australia by a pay-tv company calledGalaxy.

Galaxy went out of business several years ago, so there are a lot of un-used Conifer antennas onpeople's roofs in Australia.

The most common Conifer antenna used by Galaxy is the 18dBi grid, while the 24dBi grid is a littleless common. Note that both the 18dBi and 24dBi grids use an identical feedhorn, so this page isapplicable for both.

18dBi and 24dBi ex-Galaxy antennas made by Conifer,with a 30cm ruler (bottom right) for scale (Enlarged to show texture and for larger screens)
http://www.vallstedt-networks.de/Fotogalerien/Doppelacht/doppelacht.htmhttp://www.vhfman.freeuk.com/radio/23cmantennas.htmlhttp://www.andrew.com/http://www.vallstedt-networks.de/Fotogalerien/Doppelacht/doppelacht.htmhttp://www.vhfman.freeuk.com/radio/23cmantennas.htmlhttp://www.andrew.com/


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However, the Conifer antennas used by Galaxy were designed to operate at a different frequency thanwireless networking, and have a down-convertor integrated in the feedhorn.

They need to be modified before they can be used for 802.11b wireless networking, and this pagedescribes one way to modify them, achieving very good results.

an 18dBi Conifer (as installed by Galaxy) (Enlarged to show texture and for larger screens)

Background:

Numerous people have posted guides on modifying Conifer antennas (ex-Galaxy) for use with wirelessnetworking. Most of these guides show how to disasemble the feedhorn, cut off the end of the down-converter PCB, and solder coax onto the PCB dipole.


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the most common mod - coax soldered to the cut pcb (Enlarged to show texture and for larger screens)

Of all the sites out there, ChrisK's page on his Galaxy modification(http://www.narx.net/~chrisk/WaFreeNet/GalaxyMod/) was the most interesting, as he rebuilt thedipole from scratch, ensuring the measurements of the dipole and balun were as accurate as possible foroperation at 2.4GHz.

ChrisK based his dipole on a design shown on thispage(http://www.saunalahti.fi/~elepal/antenna1.html), and Marcus and myself believed we couldconstruct similar or better dipoles, and decided to use a brass plate for the dipole (instead of the thinbrass tube which ChrisK has used).

To ensure the correct balun impedance of 50 ohms, the ratio of the inner diameter of the copper tube tothe outer diameter of the brass rod should be approx 2.3.

The important dimensions are:

length of the dipole is 1/2 wavelength

length of the balun is 1/4 wavelength ratio of inner diameter of copper tube to outer diameter of brass rod

The 802.11b standard uses 2.412MHz to 2.484MHz frequency range, so at the centre of that frequencyrange, 1/2 wavelength is 61mm, and 1/4 wavelength is 30.5mm.

Below is a cut-away diagram showing the parts used in the construction of the dipole.
http://www.narx.net/~chrisk/WaFreeNet/GalaxyMod/http://www.narx.net/~chrisk/WaFreeNet/GalaxyMod/http://www.saunalahti.fi/~elepal/antenna1.htmlhttp://www.saunalahti.fi/~elepal/antenna1.htmlhttp://www.narx.net/~chrisk/WaFreeNet/GalaxyMod/http://www.narx.net/~chrisk/WaFreeNet/GalaxyMod/http://www.saunalahti.fi/~elepal/antenna1.htmlhttp://www.saunalahti.fi/~elepal/antenna1.html


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diagram showing components fitted together (Enlarged to show texture and for larger screens)

Parts Required:

The materials we used to perform this modification:

Conifer (ex Galaxy) antenna

low-loss coax (such as LMR-400 or CNT-400) 50mm of copper pipe (~10mm internal diameter)

61mm of flat brass bar (~12mm wide by ~0.5mm thick)

30.5mm of brass pipe (~4-4.5mm outer diameter)

female n-connector


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the raw materials: copper pipe, brass tube, brass plate (Enlarged to show texture and for larger screens)

Most Bunnings and Mitre10 hardware stores should stock these materials - ask at the trade counter ifyou can't find them.Alternatively, hobby stores should certainly stock these materials.

The brass plate I used is 12mm wide, and 0.6mm thick, while the copper pipe has an internal diameterof 10.8mm, and the brass tube is labelled as "3/16 round brass - stock no 129" with an externaldiameter of 4.5mm.This means the ratio of the inner diameter of the copper to the outer diameter of the brass is10.8/4.5=2.4, which is close enough to the required ratio of 2.3.

Antenna Disassembly:

Start by disassembling your Conifer antenna.Remove the 2 or 4 bolts which attach the mounting bracket and the feedhorn to the dish.

Remove the reflector from end of the feedhorn by removing the small screw in the centre of it.


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remove the screw holding the reflector onto the feedhorn (Enlarged to show texture and for largerscreens)

Remove the nose cone from the feedhorn. Some people have reported being able to remove the nose

cone after cracking the glue with a hammer and screwdriver.


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I normally use a hacksaw to cut alongthe join to remove the nose cone fromthe feedhorn. Other people havereported carefully squeezing the endof the feedhorn in a vice will crack theglue, allowing the nose cone to be

removed.

cutting the nose cone (Enlarged to show texture and for larger screens)


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the feedhorn with the nose cone removed (Enlarged to show texture and for larger screens)

Remove the nut and washer from the base of the feedhorn, and remove the down-convertor from thefeedhorn.


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remove the nut & washer at the base of the feedhorn (Enlarged to show texture and for larger screens)

the down-convertor (Enlarged to show texture and for larger screens)


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A hammer may be necessary to persuade the down-convertor to separate from the feedhorn.

Separate the metal feedhorn base from the plastic body of the feedhorn, and remove the sticky glueresidue using mineral turps.

remove the sticky glue residue (Enlarged to show texture and for larger screens)

You'll have to drill out the feedhorn base to approx 10-11mm in order to be able to fit the coax throughit.

Secure the feedhorn base in a bench vice, and carefully enlarge the hole until you can fit your chosencoax through it.


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drilling out the hole in the base (Enlarged to show texture and for larger screens)

I found a 10mm masonary drill bit at very slow speed works quite well.

Dipole Construction:

Start by cutting off a 50mm length of copper pipe, and cut some slots in one end, making the length ofthe slots as close as possible to 30.5mm.


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cleaning up the copper pipe (Enlarged to show texture and for larger screens)

I clean up the pipe by holding it in the chuck of my drill (holding the drill on the workbench), and thenusing sandpaper and a file on the rotating pipe.

the completed copper pipe with slots

(Enlarged to show texture and for larger screens)

Cut off 30.5mm of the small brass tube to make the balun, and clean up the ends with a file.Using a small drill bit, drill a hole near one end of the brass tube. This hole will make it easier to solderthe coax core into brass tube.


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the hole in the balun (Enlarged to show texture and for larger screens)

For the dipole, we used some brass plate, approx 12mm wide by 61mm long. The length of the brassplate isn't too critical just yet, as long as it's at least 61mm long. It'll be trimmed to the correct lengthonce the parts have been soldered together.Mark the centre of the brass plate, as this is where you'll have to solder the small brass pipe.

mark the centre (Enlarged to show texture and for larger screens)

Then hold the copper pipe against the brass plate (with the slotted end against the brass plate), andmark it's location.

mark the location of the copper pipe (Enlarged to show texture and for larger screens)

Then hold the copper pipe against the brass plate, and mark it's location


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mark the line to cut (Enlarged to show texture and for larger screens)

Now cut the brass plate along the blue line, and clean up the cut ends with a file. I find a juniorhacksaw works quite well for this.

the brass plate after being cut (Enlarged to show texture and for larger screens)

Clean up the cut edges, and remove the tarnish with some sandpaper.

the polished brass plate (Enlarged to show texture and for larger screens)

We've used both RG-213 and CNT-400 coax for these modifications, and they require slightly differentapproaches to the coax core.Note that CNT-400 or LMR-400 is recommended, rather than RG-213, due to the lower impedance.


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Strip approx 30mm of the black outer sheath off the coax.

RG-213 coax with the outer sheath stripped off (Enlarged to show texture and for larger screens)

Fold the braid back over the remaining outer sheath.

the braid folded back (Enlarged to show texture and for larger screens)

Strip off the central insulation, and if using coax with a stranded core (ie, RG-213), double each strandof the core over, and tighten up the bends with a pair of pliers.


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the core folded over (Enlarged to show texture and for larger screens)

Fit the brass tube over the coax core, with the hole previously drilled being located closest to the coax.Solder the brass tube to the coax core, using the hole to supply solder onto the join.

the brass tube soldered onto the coax core (Enlarged to show texture and for larger screens)

Push the copper pipe over the folded-back braid on the coax, until the brass tube protrudes past the endof the copper pipe by at least a few millimetres.Note that you may need to un-braid the coax braid, to as it is a pretty tight fit.


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the copper pushed onto the coax (Enlarged to show texture and for larger screens)

Tin the two pieces of the brass plate where they need to be soldered to the brass tube and the copperpipe.


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the tinned brass plate

Tin the end of the brass tube and the end of the copper pipe with some solder.Solder the brass tube onto the previously marked centre point on the larger of the two brass platehalves.

the brass tube soldered to one half of the dipole (Enlarged to show texture and for larger screens)

Now slide the copper pipe down against the brass plate, and solder it to the brass plate, ensuring thetwo slots are aligned against the long sides of the brass plate.


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the copper pipe soldered to one half of the dipole (Enlarged to show texture and for larger screens)

Solder the other half of the brass plate to the copper pipe, ensuring there's an air gap of approximately1mm between the two brass plate sections.


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the assembled dipole (Enlarged to show texture and for larger screens)

Measure the overall length of the brass plate, and trim the length to make it 61mm long. This is thedipole, and its length should be as close to 1/2 wavelength as possible.


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Using the original dipole as a template, measure, mark and drill the the holes in each end of the dipole.These holes are used to locate and hold the dipole in the feedhorn.

If you've got access to a coax crimper, use it to crimp the copper pipe onto the coax braid, to ensure avery firm connection, and trim the excess braid which is still protruding past the end of the copper pipe.

two holes drilled in the dipole, (Enlarged to show texture and for larger screens)and the copper crimped onto the coax

Reassembly:

The dipole can then be installed into the feedhorn. Use some silocone or hot-melt glue on the ends ofthe dipole, to ensure it won't become dislogded.


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the dipole installed into the feedhorn, (Enlarged to show texture and for larger screens)and fixed into place with hot-melt glue

Glue the feedhorn into the metal base, using a high-strength glue, such as 24hr Araldite.


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the feedhorn glued into the base with Araldite (Enlarged to show texture and for larger screens)

Glue the nose cone onto the end of the feedhorn.Re-assemble the antenna, and use silicone or hot-melt glue to seal up the back of the feedhorn (wherethe coax enters the feedhorn).


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seal the base with silicone (Enlarged to show texture and for larger screens)

Terminate the other end of your coax with a female N connector.

a female N connector (Enlarged to show texture and for larger screens)

To minimise the stress on the coax where it exits the rear of the feedhorn, use a cable tie to firmlyattach it to the antenna mounting bracket, as shown in the photo below.The two U-bolts provide sufficient clearance for the coax between the mast and the bracket, and you


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can use the existing holes in the bracket.

coax cable-tied to the bracket

The cable tie ensures the coax will not move inside the feedhorn. This is particularly important whenusing a fairly stiff coax, such as CNT-400. Failure to properly secure the coax in this way can result inthe coax moving while you mount the antenna on a mast, and this can lead to broken dipoles.

You're now ready to test it!

Note that most people using Conifer antennas for wireless networking have them horizontally polarised- that is, they are rotated 90 degrees compared to the way Galaxy mounted them (ie, long axis of thegrid is vertical for wireless networking, instead of horizontal).


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Antenna Comparison Testing D.

This page details the testing method and results when testing some downpipe waveguides, a collinear,some biquads, a cantenna, and a modified Conifer dish.

Background of Same Technician:

Over the past several months, I'd constructed a number of antennas, including some biquads, an 8-element collinear omni, and a cantenna, and Marcus had recently constructed some 8-slot 180-degreewaveguide antennas using cheap downpipe.

We wanted to test the waveguides, and compare the performance of the various antennas.By testing all the antennas in a single session, using identical configurations in the same location,allows us to easily compare the performance of the various antennas, as there are minimal factorswhich would be affecting the results.

Test Equipment:

We used two laptops, one at either end of our wireless link.

The specs for the laptop at the remote end:

Pentium III 1GHz with 128Mb RAM

Enterasys RoamAbout wireless card

Windows 2000 SP2

Enterasys 7.44 drivers and client utility

running on battery power for the duration of the tests

The specs for the laptop at the antenna end: Pentium III 700MHz with 256Mb RAM

Enterasys RoamAbout wireless card

Windows 2000 SP2

Enterasys 7.44 drivers and client utility

running on battery power for the duration of the tests

AntennasWe had the following antennas to test:

modified 24dBi Conifer (ex-Galaxy) dish

cantenna two biquads

two 8-slot 180-degree downpipe waveguides

8-element collinear omni antenna

The 24dBi Conifer dish has been modified by myself, with a custom-made copper and brass dipole.This is my reference antenna, and has been used in previous antenna testing sessions (referred to asFeedhorn #3 in the May 2002 Conifer Antenna Testing, and m3 in the September 2002 Conifer
http://www.enterasys.com/products/items/CSIxD-AA/http://www.enterasys.com/software/RoamAbout/RoamAbout-Client-WIN95-98-2000-ME-NT-XP-744-pkg.ziphttp://www.enterasys.com/products/items/CSIxD-AA/http://www.enterasys.com/software/RoamAbout/RoamAbout-Client-WIN95-98-2000-ME-NT-XP-744-pkg.ziphttp://martybugs.net/wireless/conifermods.cgihttp://martybugs.net/wireless/conifermods.cgihttp://martybugs.net/wireless/conifertest.cgihttp://martybugs.net/wireless/conifertest2.cgihttp://www.enterasys.com/products/items/CSIxD-AA/http://www.enterasys.com/software/RoamAbout/RoamAbout-Client-WIN95-98-2000-ME-NT-XP-744-pkg.ziphttp://www.enterasys.com/products/items/CSIxD-AA/http://www.enterasys.com/software/RoamAbout/RoamAbout-Client-WIN95-98-2000-ME-NT-XP-744-pkg.ziphttp://martybugs.net/wireless/conifermods.cgihttp://martybugs.net/wireless/conifermods.cgihttp://martybugs.net/wireless/conifertest.cgihttp://martybugs.net/wireless/conifertest2.cgi


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Antenna Testing II).

The cantenna was constructed by myself using a steel can with diameter of 100mm, and a length of175mm, with a panel-mount N connector riveted into the appropriate location.

the panel-mount N connector

the feed inside the cantenna

The first biquad (referred to as biquad1) was constructed in a similar way to those made by TrevorMarshall, and has two "lips" on the sides of the reflector. This biquad had approximately 2m of CNT-400 coax attached to it.

The other biquad (referred to as biquad2), is the one featured on my Biquad Antenna Constructionpage. A short length of CNT-400 coax is attached to this biquad.
http://martybugs.net/wireless/conifertest2.cgihttp://martybugs.net/wireless/antennacomp.cgi#refhttp://martybugs.net/wireless/antennacomp.cgi#refhttp://martybugs.net/wireless/biquad/http://martybugs.net/wireless/conifertest2.cgihttp://martybugs.net/wireless/antennacomp.cgi#refhttp://martybugs.net/wireless/antennacomp.cgi#refhttp://martybugs.net/wireless/biquad/


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biquad1

biquad2

Note that biquad1 has not been built optimally, as it is not correctly impedance matched (due to the useof the wire stakes to mount the biquad to the reflector).Biquad2 has been constructedwith the coax extending through the reflector, encased in the copper pipefor additional strength.

The collinear was constructed using 8 elements of CNT-400 coax, as per the details atwireless.gumph.org, with the dimensions appropriately adjusted to suit the velocity factor of CNT-400coax.

the collinear nearly complete

It has been mounted inside a length of 25mm electrical conduit, to provide some physical strength, andto weather-proof it.
http://martybugs.net/wireless/biquad/http://martybugs.net/wireless/biquad/http://wireless.gumph.org/articles/homemadeomni.htmlhttp://martybugs.net/wireless/biquad/http://wireless.gumph.org/articles/homemadeomni.html


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the completed collinear

Marcus constructed the two 8-slot 180-degree waveguides using readily available downpipe.The first is based on Trevor Marshall's design (referred to as the TM waveguide), while the second isbased on Rob Clark's design (referred to as the RC waveguide).

the two completed waveguides(RC waveguide on the left, TM waveguide on the right)

Test Setup:

We placed one laptop on the parcel shelf of a car which we parked approximately 200m down the road.No external antenna was connected to this laptop - we were relying on the internal antenna in theRoamAbout card.
http://planetaxis-web.sytes.net/wireless/downpipe.cgihttp://trevormarshall.com/waveguides.htmhttp://trevormarshall.com/waveguides.htmhttp://nuke.freenet-antennas.com/modules.php?name=News&file=article&sid=1http://nuke.freenet-antennas.com/modules.php?name=News&file=article&sid=1http://planetaxis-web.sytes.net/wireless/downpipe.cgihttp://trevormarshall.com/waveguides.htmhttp://nuke.freenet-antennas.com/modules.php?name=News&file=article&sid=1


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the remote laptop is in the red car (circled), approx 200m distant,with the top of a waveguide shown in the foreground

Each antenna was connected to the wireless card in the other laptop using a 2 metre length of RG213coax (terminated with a male N connector at one end, and a female N connector at the other end), and

an appropriate pigtail, with the wireless cards at both ends configured to operate in ad-hoc mode.

testing the waveguide testing the collinear


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testing the cantenna

Testing Methodology:

The "Link Test" mode in the Enterasys Client Utility was used to monitor the link strength, with eachtest configuration being monitored for a couple of minutes.

the Enterasys Client Utility displaying link statistics

Once the reported link details had stabilised, the SNR, signal strength and noise level were recorded forboth the local and remote ends of the link were recorded.

All antennas were tested in both horizontal and vertically polarised orientations.For horizontal polarisation, the waveguides are vertical, the biquad is vertical, the collinear is


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horizontal, the cantenna feed element is horizontal, and the Conifer dish is vertical.For vertical polarisation, all antennas were rotated 90 degrees.

The waveguides were briefly tested on channels 1, 6 and 11, and as they performed best on channel 6,this channel was used for all subsequent testing of the waveguides and all other antennas.

As we wanted to plot azimuth graphs for the two waveguides, we measured the signal, noise and SNRdetails after rotating the waveguides at 10 degree intervals.

testing the waveguides at different angles

Signal readings at different rotation angles of the waveguides were only made with the waveguidehorizontally polarised, as it is designed to operate in this orientation.

Test Results & Calculations:

The tables below show the recorded signal, noise and SNR values for both the local (ie, the laptopconnected to the antenna) and remote (ie, the laptop in the car) ends of the connection.


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To calculate the gain of each antenna, the remote signal readings were normalised, using the recordedresults for the 24dBi Conifer dish.The remote signal readings provide an indication of the transmit performance of each antenna.Note that the gain of the Conifer dish has been conservatively estimated at 22dBi.

The normalised results for each antenna are:

Azimuth plots of the transmit performance have been generated for each of the waveguides, showingthe performance over 360 degrees.Note that testing was only performed over 180 degrees, but some quick tests indicated the results forthe other 180 degrees were within 1 or 2 dB.


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Refer to Marcus'page for more details on the waveguide test results, and additional azimuth plots.

These azimuth plots almost exactly match the theoretical azimuth plots which Trevor Marshall showson his webpage.

Comments & Conclusions:

By testing all the antennas in the same location, on the same day, using the same hardware at both ends,

we've attempted to minimise any factors which may affect the results.

When calculating the normalised gain of the antennas, we assumed the gain of the 24dBi Conifer was22dBi.

Our results generally agree with the antenna gains other people have reported.

Claimed gains for the biquads are typically 10-12dBi, while we measured 8-12dBi.Interestingly enough, biquad1 measured 10-12dBi, while biquad2 measured 2dBi less when verticallypolarised, despite having a stub (the mount between the reflector and the quad itself) which isimpedance matched.

I'd suggest these differences are due to the lips on biquad1, which would reduce the beamwidth of theantenna somewhat.

Various people have reported gains for the 8-element collinear anywhere between 6-10dBi (6dBi forRG-213 construction, while my collinear uses CNT-400), while we measured 8-10dBi.

Similarly, people have reported cantenna with gains varying from 10-14dBi, while my cantennameasured between 12 and 13dBi in these tests.
http://planetaxis-web.sytes.net/wireless/downpipe.cgihttp://trevormarshall.com/waveguides.htmhttp://planetaxis-web.sytes.net/wireless/downpipe.cgihttp://trevormarshall.com/waveguides.htm


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The theoretical gain of the TM waveguide is 15dBi (according to Trevor Marshall), whilecommercially available 8-slot 180-degree waveguides are marketed with gains between 14 and 16dBi.Our results show the gain of the TM waveguide being 14-17dBi, and the gain of the RC waveguidebeing 16-19dBi.

The RC waveguide provides approximately 2dBi more gain than the TM waveguide, which is

consistent with Rob Clark's testing.

Note that the dimensions of the downpipe are slightly different than the aluminium tubing used byTrevor Marshall, but the slot spacing was not adjusted to compensate for this.However, when constructing the RC waveguide, the measurements were re-calculated to suit thedownpipe dimensions, and was adjusted to have a air column length of 5 wavelengths (while the TMwaveguide has an air column length of 4.75 wavelengths).

We intend to perform some more testing with the waveguides, and I'll update this page with the results,when they are available.

During our testing, we noticed that while the cantenna and the Conifer dish have a very narrowbeamwidth (Conifer specs say 7 degrees), the biquad have a very wide beamwidth.With such a wide beamwidth, the biquad is extremely easy to aim, while antennas with a narrowbandwidth can be more difficult to aim.

Review of WarDrivingWorld DIY Biquad Kit E.Copied from martybugs.net page and did not change anything to make it more book professional

Review of WarDrivingWorld DIY Biquad Kitauthor: Martin "mpot"Potpublished: 11 November 2006

This review looks at a DIY biquad antenna kit from WarDrivingWorld.com, for making an 802.11b/gwireless networking antenna. The contents of the kit are reviewed, and comments are provided on theconstruction of the antenna. The completed antenna is then tested and compared with several otherbiquad antennas.

BackgroundSeveral years ago, I published detailed instructions on building a biquad antennaon my website.

The biquad is relatively easy to build yourself, and offers very good performance for its size andcomplexity. A biquad typically has a gain of 11dBi, with approximately 40 degree beamwidth. It can be

used as a standalone antenna, or it can be used as a feed on a larger dish.

While many people have used my instructions to build their own biquad antennas, some people do notnecessarily have the tools required to construct these antennas, or do not know where to source thecomponents required.

WarDrivingWorld.com is addressing this by selling complete DIY kits for biquad antennas.When I checked theireBay store, they were selling these DIY biquad kits, complete with a 1.5m pigtailof your choice, for US$22.95 plus US$5.50 postage and handling.
http://trevormarshall.com/waveguides.htmhttp://nuke.freenet-antennas.com/modules.php?name=News&file=article&sid=1http://nuke.freenet-antennas.com/modules.php?name=News&file=article&sid=1http://martybugs.net/wireless/biquad/http://martybugs.net/wireless/biquad/http://martybugs.net/wireless/biquad/http://wardrivingworld.com/http://stores.ebay.com/War-Driving-Worldhttp://trevormarshall.com/waveguides.htmhttp://nuke.freenet-antennas.com/modules.php?name=News&file=article&sid=1http://martybugs.net/wireless/biquad/http://martybugs.net/wireless/biquad/http://wardrivingworld.com/http://stores.ebay.com/War-Driving-World


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WarDrivingWorld sent me a kit to review, as they had previously asked if they could distribute aprintout of my Biquad Antenna Construction page with their kits. The kit arrived in a USPS cardboardenvelope with a US-based source address.

mail package

There was no additional padding in the envelope, but due to the relatively thick cardboard construction,there is little chance of the kit getting damaged in the mail.

Also included in the envelope was this rather cheesy sticker promoting the WarDrivingWorld websitethat sells these kits.

sticker and business card

The sticker is cheaply made, and was folded over to fit into the envelope, and as a result, the letteringon the printed side stuck together. Despite attempting to separate it carefully, the text was damaged (themissing part of the last "d" of "WarDrivingWorld" is visible just to the left of the first "W" of

"WarDrivingWorld").

I have no idea why the sticker has a photo of Arnie on it...

Kit ContentsThe WarDrivingWorld kit comes complete with all the parts required to build a biquad antenna, and isneatly packaged in a sealed plastic bag.
http://martybugs.net/wireless/biquad/http://martybugs.net/wireless/biquad/


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bag containing the kit

Contents of the bag are:

pre-drilled copper PCB (123x123mm)

female panel-mount N-connector with solder lug

approx 350mm 2.5^mm copper wire

short length of silver solder

Apparently these kits normally come with a 1.5m pigtail, but I did not receive a pigtail with my kit.Similarly, I did not receive any instructions, but apparently a printout of my Biquad AntennaConstruction page is normally included with the kit (and is used with my permission).

contents of the kit
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The length of silver solder provided with the kit is lead-free. Apparently silver solder is moreconductive than tin/lead solder, due to its silver content, and produces joints which can be upto 5-10times stronger than joints made with tin/lead solder.Silver solder also has a lower melting point than tin/lead solder, thus allowing it to be used with lessheat than similar tin/lead solder.

The copper PCB measures 123x123mm, and has a hole pre-drilled in the centre for the N-connector.The hole is not cleanly drilled - it has rough edges, and is not circular, and probably is a little largerthan is necessary. However, the edges of the hole can be easily cleaned up with a round file in a minuteor two.

ConstructionThe copper surface of the PCB was cleaned up with some steel wool. It is important to clean the coppersurface around the hole in the centre of the PCB, to ensure a good electrical connection when the N-connector is screwed into place.Also, aesthetically, a polished copper surface looks much nicer than an oxidised surface. However, thecopper surface will oxidise again, and will not retain its polished appearance (unless it is sealed), butthe oxidisation should have no impact on the performance of the antenna.

As already mentioned, the burrs on the edges of the hole in the centre of the PCB were removed with asmall round file.

The copper wire was straightened, and then bent into the shape required for the biquad element, witheach side being as close to 30.5mm as possible. (Refer to the Biquad Antenna Construction page formore details.)

biquad element

The N-connector was inserted into the hole in the PCB, with the solder end on the copper side of thePCB, and the N-connector end on the blank side of the PCB.

Note that I placed the washer with the solder lug on the copper side of the PCB too, and bent the solderlug up at a 90 degree angle, to allow it to be used as an attachment point for the element feed.

To build the biquad element feed, a short length of copper wire was soldered into the centre post of theN-connector, and another was attached to the solder lug. Once attached, these two wires were measuredand trimmed at approx 14.5mm away from the PCB copper surface (to ensure the biquad elementwould be 15mm away from the PCB).

I cut two pieces of wood 14.5mm thick, and used these to support the biquad element while soldering it
http://martybugs.net/wireless/biquad/http://martybugs.net/wireless/biquad/


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to the feed on the N-connector.

soldering the biquad element

The Biquad Antenna Construction page mentions the need for a shielded feed to the biquad element (ie,the section between the biquad element and the PCB reflector).

However, the WarDrivingWorld kit only provides components for building a biquad with an unshieldedfeed. An unshielded feed will radiate, and this will have a detrimental impact on the antenna'sperformance.(Refer to the test results below for more details on performance.)

side view of element mounting detailshowing the solder lug attachment on the right
http://martybugs.net/wireless/biquad/http://martybugs.net/reviews/biquad.cgi#testinghttp://martybugs.net/wireless/biquad/http://martybugs.net/reviews/biquad.cgi#testing


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element mounting detail

The resulting biquad antenna is somewhat fragile, as the biquad element can easily be bent or knockedout of shape.

completed biquad antenna

This can be rectified by using a plastic spacer between the edges of the biquad element and the PCBreflector, to securely hold the biquad element in place, and to make the antenna much more robust.

I use plastic spacers, made out of a small section of reticulation riser, with a small cable tie through it.

detail of plastic spacer
http://martybugs.net/wireless/biquad/double.cgi#spacershttp://martybugs.net/wireless/biquad/double.cgi#spacershttp://martybugs.net/wireless/biquad/double.cgi#spacers


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Note that the spacers can be made from almost any non-metallic (microwave-transparent) material. Ifdesired, hot-melt glue can be used to attach the spacers, but be aware that the hot-melt glue will getvery soft if you mount your biquad in direct sunlight.

TestingTo test the effectiveness of the WarDrivingWorld biquad, I compared its performance with one of my

martybugs biquad antennas, and with a martybugs double biquad antenna.

Note that the martybugs biquad has a shielded feed, and has a slightly smaller PCB reflector(110x110mm, while the WarDrivingWorld biquad has a 123x123mm biquad). The smaller reflector isdue to the fact that the martybugs biquad was originally built to be used as a feed on a dish.

All antennas were tested by connecting them to an 30mW 802.11b Enterasys RoamAbout wirelessPCMCIA card in a laptop, withNetStumbler 0.4.0 being used to monitor signal, noise and SNR.

Firstly, all antennas were used to establish a connection to the 180 degree slotted waveguide mountedon my roof(aWAFreeNet AP called "SGNet"; which has a Minitar MNWAPB access point), from adistance of approx 50m.

Test results for a client connection to SGNet:

antennaSNR

(dB)signal

(dBm)noise

(dBm)SNR diff

(dBm)

martybugs biquad 47 -54 -101

WarDrivingWorld biquad 46 -55 -101 -1

martybugs double biquad 51 -51 -102 +4

A similar test was performed by establishing a client connection to the 360 degree slotted waveguide on

ArmadaleAP, anotherWAFreeNet access point, approx 300m away (which has an Orinoco RG1000access point).

Test results for a client connection to ArmadaleAP:

antennaSNR

(dB)signal

(dBm)noise

(dBm)SNR diff

(dBm)

martybugs biquad 26 -73 -99

WarDrivingWorld biquad 25 -76 -101 -1

martybugs double biquad 28 -74 -102 +2

The test results indicate that the gain of the WarDrivingWorld biquad is about 1dBi less than that of themartybugs biquad. This is due to the unshielded feed on the WarDrivingWorld biquad, while themartybugs biquad has a shielded feed.Note that the dB scale is logarithmic (where 3dBi is a doubling of signal strength), and 1dBi isapproximately equivalent to 25% of the signal.

Note that the martybugs biquad had a slightly smaller reflector (110x110mm instead of 123x123mm),so the difference in performance between the two biquads may be slightly more than 1dBi if a123x123mm reflector were to be used on the martybugs biquad.
http://martybugs.net/wireless/biquad/http://martybugs.net/wireless/biquad/double.cgihttp://netstumbler.com/downloads/http://martybugs.net/wireless/mast.cgihttp://martybugs.net/wireless/mast.cgihttp://wafreenet.org/http://wafreenet.org/http://martybugs.net/wireless/armadale/http://wafreenet.org/http://martybugs.net/wireless/biquad/http://martybugs.net/wireless/biquad/double.cgihttp://netstumbler.com/downloads/http://martybugs.net/wireless/mast.cgihttp://martybugs.net/wireless/mast.cgihttp://wafreenet.org/http://martybugs.net/wireless/armadale/http://wafreenet.org/


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The parts and routers needed for Covac F.

This document only includes the satellite because it's the best system for covac and would be morecovert then a cantenna because it looks almost like a ordinary dish satellite except for the biquadextension but would fool an average quick spies and surveillance crews just quickly checking for wifi

boosters. Now we will move on to what you will need next to meet the guidelines of Covac Internetsystems, the parts and routers needed for the Covac system.

These are some of recommendations:

I recommend wireless N because it's next generation wireless and a peer and peer wirelessinferstructure will be super slow remotely but super fast locally but in the future I bet special hackersand technicians will surpass Wireless N and make Terabit type wireless that will begin to make Covacabout as fast as DSL and Cable for every peer and transmission point.The one flaw with Wireless N is I have done some research and till now I have found no Wireless Nrouters to have detachable antennas so you may have to modify it but if there is one then I suggest you

buy it

Warning: I recommend you buy a wireless N router (Wireless G if failure to find all the guidelines)with these guidelines for sucessful Covac operations:

1. Detachable Antenna for Biquad Antenna or Cantenna assertion2. Firmware is GPL Compatible and Open to being able to upload custom firmware3. The firmware should be compatible with Official Covac modified firmware

I have gathered information from Maria from Linksystem that these routers allow modification of gplcode, have detachable antennas but are Not Wirelss N routers because she claims no wireless N routers

have detachable antennas yet.

WRT54G version 1-5, 7WRT54GC - but only one antenna can be detachedWRT54GL version 1WRT54GS version 1-6WRT54GX version 1-2WRT54G3G

I Recommend these router systems:

This wireless N lets you detach it's antenna source: http://www.babykgb.com/products/158/7/1/332306

Belkin Wireless Pre-N (F5D8230tt4) Router Features Include:

# 800% greater coverage than standard 802.11g - Belkin Pre-N providesthe industry's best wireless coverage, extending your range withimproved reliability and fewer drops.

# 600% greater speeds than standard 802.11g - Belkin Pre-N provides


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the industry's fastest wireless connection for gaming, streaming video, Voice over IP, and moving largefiles efficiently and quickly between all the devices in your networked home.

# Improved performance of standard 802.11g and 802.11b networking devices - Using a Belkin Pre-NRouter or Card with an older 802.11g or 802.11b networking product increases wireless coverage up to20%.

# Improved resistance to wireless interference - Belkin Pre-N products sense potential interference anddynamically shift to the clearest wireless channel available.

# Belkin Pre-N products do not drop to the lowest networking speed in a mixed-mode environment - Ifa standard 802.11g or 802.11b device is introduced into a Belkin Pre-N network.

# The Belkin Pre-N product will not drop to the standard 802.11g or 802.11b speeds - Belkin Pre-Nproducts will continue to transmit at a link rate of 108Mbps, a result competing products cannotachieve.

# Advanced Security - Wi-Fi Protected Access (WPA) support provides enhanced encryptionprotecting your wireless network.

# Pop-up Blocker - 6 months of free pop-up, adware, and spyware stopper

# Web Content/Parental Control Filter - Web Content/Parental Control Filter 6 months of free built-inparental Control/Web Content Filter provides over 50 fully configurable filters that allow you to blockwebsites and images.

Warning this router may not allow GPL Modifications to it's firmware so hacking the firmware may beonly way to set up the Covac system and is not illegal but will void the warranty unless provided by aactive service then hacking the router may be illegal in your area.

Zyxel NBG-415N Draft 802.11n Wireless Router, IEEE 802.11b/gWireless Technology, 2 x 4dBi Dipole Antenna Non-detachable and 1 x

4dBi Dipole Antenna Detachable Antenna, 300Mbps Transmission Speed,

10Mbps Ethernet Full-duplex and 100Mbps Fast Ethernet Full-duplex

Data Transfer Rate (NBG415N NBG 415N NBG-415N)

Warning this router may not allow GPL Modifications to it's firmware sohacking the firmware may be only way to set up the Covac system and is

not illegal but will void the warranty unless provided by a active service then hacking the router may beillegal in your area.

Zyxel NBG-415N Draft 802.11n Wireless Router, IEEE 802.11b/g Wireless Technology, 2 x 4dBiDipole Antenna Non-detachable and 1 x 4dBi Dipole Antenna Detachable Antenna, 300Mbps

Transmission Speed, 10Mbps Ethernet Full-duplex and 100Mbps Fast Ethernet Full-duplex Data

Transfer Rate, 1 x RJ-45 10/100Base-TX Auto MDI/MDI-X WAN and 4 x RJ-45 10/100Base-TX AutoMDI/MDI-X LAN Interfaces/Ports, Twisted Pair Connectivity Media, 5 V DC Device Input Voltage.

General Information


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Manufacturer Zyxel

Manufacturer Part Number NBG-415N

Product Line Routers

Product Name NBG-415N Draft 802.11n Wireless Router

Marketing Information

The ZyXEL's NBG-415N Draft 802.11n Wireless Router is the perfect solution for home usersdemanding cutting-edge, versatile networking devices. Taking advantage of Draft IEEE 802.11n

technology, the NBG-415N can efficiently pinpoint client computers and select adequate methodsto exchange radio signals. Coupled with Draft 802.11n clients, the NBG-415N can truly push

wireless coverage to the limit. With the upcoming IEEE 802.11n technology, the NBG-415N caneliminatedead zones and extend coverage up to 4 times, while retaining the backward-

compatibility with all 802.11b/g devices.Features

IEEE 802.11b/g Wireless Technology

2 x 4dBi Dipole Antenna Non-detachable and 1 x 4dBi Dipole Antenna Detachable Antenna 300Mbps TransmissionSpeed

10Mbps Ethernet Full-duplex and 100Mbps Fast Ethernet Full-duplex Data Transfer Rate

1 x RJ-45 10/100Base-TX Auto MDI/MDI-X WAN and 4 x RJ-45 10/100Base-TX Auto

MDI/MDI-X LAN Interfaces/Ports

Twisted Pair Connectivity Media

5 V DC Device Input Voltage

WPA and WPA2Wireless Security

Specifications

Wireless Specifications Wireless Technology IEEE 802.11b/g Antenna 2 x 4dBi Dipole Antenna

Non-detachable1 x 4dBi Dipole Antenna Detachable Frequency Band/Bandwidth 2.4 GHz IEEE 802.11b/g ISM

Band Transmission Speed 300Mbps Transmission Speed Details 300Mbps

54Mbps Auto-fallback IEEE 802.11g6Mbps IEEE 802.11g

11Mbps Auto-fallback IEEE 802.11b

1Mbps IEEE 802.11b Wireless Security WPAWPA2 Interfaces/Ports Interfaces/Ports 1 x RJ-45 10/100Base-TX Auto MDI/MDI-X WAN

4 x RJ-45 10/100Base-TX Auto MDI/MDI-X LAN Media & Performance Connectivity MediaTwisted Pair Data Transfer Rate 10Mbps Ethernet Full-duplex

100Mbps Fast Ethernet Full-duplex Management & Protocols Management StreamEnginefor QoS

DHCP Server/ClientEmbedded Web GUI Security SPI Firewall

DMZVPN pass-through Power Description Input Voltage 5 V DC Device Physical Characteristics

Dimensions 1.3" Height x 5.91" Width x 7.48" Depth Weight 14.53 oz

Source: http://salestores.com/zyxelnbg.html
http://salestores.com/zyxelnbg.htmlhttp://salestores.com/zyxelnbg.html


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D-Link DIR-655 model 86285E Systems D-Link Xtreme N Gigabit Router

DIR-655 Wireless Router, IEEE 802.11b/g Wireless Technology, 3 xDetachable Antenna, 2.4 GHz IEEE 802.11b/g ISM Band Frequency

Band/Bandwidth, 10Mbps Ethernet, 100Mbps Fast Ethernet and 1Gbps

Gigabit Ethernet Data Transfer Rate, 54MbpsTransmission Speed,

54Mbps Auto-fallback IEEE 802.11g (DIR 655 DIR655 862-85E 862 85E)

D-Link DIR-655 model 86285E Systems D-Link Xtreme N Gigabit Router DIR-655 Wireless Router,

IEEE 802.11b/g Wireless Technology, 3 x Detachable Antenna, 2.4 GHz IEEE 802.11b/g ISM BandFrequency Band/Bandwidth, 10Mbps Ethernet, 100Mbps Fast Ethernet and 1Gbps Gigabit

Ethernet Data Transfer Rate, 54MbpsTransmission Speed, 54Mbps Auto-fallback IEEE 802.11g,1Mbps IEEE 802.11b, 4 x RJ-45 LAN Interfaces/Ports.

General Information

Manufacturer D-Link

Manufacturer Part Number DIR-655

Product Line Routers

Product Name DIR-655 model 86285E Systems D-Link Xtreme N Gigabit RouterDIR-655 Wireless Router

Marketing Information

TheXtreme N DIR-655 Gigabit Router is IEEE 802.11n (draft) compliant device that delivers 14xfaster speeds and 6x faster range than IEEE 802.11g while staying backward compatible with IEEE

802.11g and IEEE 802.11b devices. Connect the Xtreme N DIR-655 Gigabit Router to a cable orDSL modem and provide high-speed internet access to multiple computers/ game consoles, and

media players. Create a secure wireless network to share photos, files, music, videos, printers and

network storage.

Features

IEEE 802.11b/g WirelessTechnology

3 x Detachable Antenna

2.4 GHz IEEE 802.11b/g ISM Band FrequencyBand/Bandwidth

10Mbps Ethernet, 100Mbps Fast Ethernet and 1Gbps Gigabit Ethernet Data Transfer

Rate

54MbpsTransmission Speed

54Mbps Auto-fallback IEEE 802.11g

6Mbps IEEE 802.11g 11Mbps Auto-fallback IEEE 802.11b

1Mbps IEEE 802.11b

4 x RJ-45 LAN Interfaces/Ports

Specifications

WirelessSpecifications

WirelessTechnology IEEE 802.11b/g


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Antenna 3 x Detachable

FrequencyBand/Bandwidth 2.4 GHz IEEE 802.11b/g ISM Band

TransmissionSpeed 54Mbps

Details 54Mbps Auto-fallback IEEE 802.11g6Mbps IEEE 802.11g

11Mbps Auto-fallback IEEE 802.11b1Mbps IEEE 802.11b

WirelessSecurity Wi-Fi Protected Access (WPA and WPA2)WEP encryption length: 64/128-bit

Interfaces/PortsInterfaces/Ports 4 x RJ-45 LAN

Media & Performance

ConnectivityMedia Category 5 Twisted PairData Transfer Rate 10Mbps Ethernet

100Mbps Fast Ethernet1Gbps Gigabit Ethernet

Management & Protocols

Security Network Address Translation (NAT)Stateful Packet Inspection (SPI)

VPN pass-through/multi-session PPTP/L2TP/IP SecPhysicalCharacteristics

FormFactor Wall-mountableWeight 0.7 lbDimensions 1.2" Height x 4.6" Width x 7.6" Depth

Source: http://salestores.com/dlink862.html

This is all I will bring out in this version of Covac backup communication systems and more will comeand/or bad pages will be taken out in next version but this information is to educate users reading thisdocument on specific Wireless N routers, I recommend getting a router that allows modifying of thesource code even if it doesn't have a detachable antenna because antennas can always be modified and

any attempt of converting your router to be apart of Covac systems will void your warranty regardlessof whether you modify the firmware or antenna but firmwares are hard to hack and could void thefunctionality of your router but it all is a chance you will have to take by creating a peer to peermininet.

I again warn you that Covac will be super slow if it was to be used nationally but with enough hackingand modification by hackers around the fields Covac can eventually become a mainstream alternativeto the Internet.

Anyways The parts and routers needed for Covac are simply, just follow these guidelines and anythingimproved will improve the network but needs to be compatiable with other Covac systems or else it

may lead to peer and peer network problems.
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Complete Guidelines for parts and routers

Quantity product/Part Description/Specific Instructions

1, 4 for multi-directinal peersharing systems, more then 8 forgeneral backups

Wireless N/G The router that uses the Covacsystem will be used to both shareand receive communications/data

1, 4 for multi-directional sharingand receiving of Wireless data, 8for spares and backups

Biquad Antenna all put together This will be what you hookup tothe router and then set itsomewhere high enough toaccept communications fromnext satellite.

1 Programming software goodenough for recompiling firmwaresource code

Visual programming or otherprogramming software capableof modifing the source codes ofrouter firmware

1, or more because the morecomputers means more power,speed and data distribution.

1 computer (optional unless youwant type of data, dns, or anyother servicing for your Covacrouting system)

The computer will be used tohost servers, such as personalDNS/Domain Services,web/secure Servers, InstantMessenger services, etc etc.

1 Clean electric generator (Optional)

This will be what will keep yourelectric bills from skyrockingfrom use of the Covac system

1 or more depending on licenses SSH Server or Modified Torsoftware

You should use encryptionbecause anybody can tap intoyour communications. Torshould be modified to work as aserver and connect other nodessince the usual Tor softwareconnects to a remote list, andwon't work on Covac unless auser is connected to the net aswell as the Covac.

1 per connection to anotherCovac router for syncing data

transfers and systems, also 1 percomputer/Server connection

Cat5/6 Ethernet Cables The cables will be used toconnect Computer servicing,

and/or non servicing systems andalso be used to connect extraCovac routers to sync databetween them and sync thesoftware and may be consideredas data intersects

1 or more as licensed Protocol blocking software Should only be used at the firststage because Any Bittorrent orP2P system used may crash the


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The software needed (All open source) to help construct the system G. and II. The software and systems in plan for the routing andnetwork operations

Now the very important part of Covac is the software, and now the software hasn't been developed yetbut once the best Covac software can be developed then that developher may contact me and I shall addhis/her system to the guidelines in this document.

So now this is the guidelines of the Covac software system:

SD Modification memory Must be less then 1GB and must allow expansionso maximum operating system memory should beat least 700MB and allow firmware expansions.

IP Address System Should be based off of special coordinates but still

should at least be based off of the old IP/4 systemsto ensure compatibility with older and neweroperating systems

255.255.255.255

# of router. ext of # of router. Ext of $ of router.Special area code or made up unique area code ofrouter not above IP Address standard number

Load Balancing All wireless systems must be balanced to allowcommunications from all side, recom,mendations

are extra backup active satellites for extrabandwidth improvements and software mustbalance all systems in the same area to loadeverything equally and allows communicationsfrom all sides without error

Router Syncing and Secure Connection -Modification for allows router to connect withother routers

The firmware system needs to allow connectionswith other Covac routers to allow larger arraycommunications in wider areas but the morelarger the array the slower the bandwidth andspeed for everybody unless the system is upgradedwith more seperate router systems. This is a very

advenaced protocol system not yet invented.Secure Connection means that if you connect to aprotected router under Secure Connection youmust request permission for a encrypted passcodeor if you already have the passcode then enter it tofully sync and connect with the neighboringrouter.

Firmware enabled encryption This will allow communications between router


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Optic or Cable, or if it is connected to asingle/multiple cable modem/s connection thenthis is a optional system to allow communicationsthrough cable to allow peer and peer controlledcable and fiber optic systems in case the wirelessgets really swamped with data transfers and high

volumes of traffic.Ethernet Syncing support It also allows not just syncing of both Wireless

and Fiber/Coaxial Cable syncing but allowsneighboring routers to connect using high speedEthernet from gigabit to megabit Ethernetsystems.

External HD, and Custom driver Support Allows users to connect and/or share resourceswith Hard Drives shared from computers and harddrives connected to the network, and also allowsother devices to be connected to the system thatare custom made byvenders/technicians/users/Admins drivers to beused, it is optional that the custom made driverscan be imported/exported and can be shared withother router admins upon request.

These are all the guidelines for the software system to be used, it is recommended that all intersects useCoaxial or Special Fiber optic cables between neighboring routers because it would increase the speedsof both users, Router Admins and allow extra systems in case one of them goes down during naturaldisasters, power outages in certain areas, thunder storms, and other reasons.

I have even designed a few example images of how the system will load and work:


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Anyways the software that is needed to help construct the system is open source software because itcan be modified to work for anything on any system so heres the list of software recommended to helpbuild your Covac system:

1. Linux/Minix (Minix is good for OLPC style laptops, and should work good on lower systemssuch as mobile devices and routers with modified memory cells to allow larger systems otherthen just firmware)

2. BIND/OpenDNS To allow a user to host their own local server/service DNS system withouthosting it on a computer and allows local routers tying into the DNS Domain Name System

3. Apache Web Server and SSL Extension (To allow the Admins and permitted users to access apage that allows configurations to be worked with on the system)

4. Jabber (for communications and relaying messages to other routers)5. Eraser (Since it's open source it can be modified to erase free space and temp space not used on

the router to protect security, and privacy6. SmoothWall, pfSense (Both open source firewalls and shouldn't have to be fancy just enough to

guard the router/routers against attacks and unauthorized intrusion.


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So looks like I talked about everything until now explains how the system shall work and what parts itshall use. It should not be used as a replacement for the Internet and just as a backup, covert, and othergood uses if anything happens to the Internet. It allos private communications but phone use might betoo much for heavily used Covac Routers until the routers are ungraded into better wireless, bettersystems, and better models.

There is one more thing I like to talk about one way to modify a router to accept a SD Card memorychipping system that will hold the operating system data.

Details for one type of router (could be used to help with all type of routers but be aware of theconsequences if you screw up

Source: http://www.dd-wrt.com/wiki/index.php/Buffalo_WHR-G54S_and_WHR-HP-G54_SD/MMC_mod

SD/MMC Modification for the Buffalo WHR-G54S and WHR-HP-G54 Wireless Router

Update: 2007-11The prior edition of this tutorial was attempted, by at least two users, specifically on WHR-HP-G54's.Of a variety of SD and MMC cards, none worked. Since then, the missing tags in the tutorial have beenadded and it works! Have Fun! Mega-shouts to Iron for an extensive tutorial.

Introduction

This tutorial guides you through adding a SD orMMC interface to the Buffalo WHR-G54S andBuffalo WHR-HP-G54 router and gives some general information and tips to help you to do the samewith other DD-WRT routers. The DD-WRT V2.4 firmware supports this modification, so there is no

need to install modules or packages. All configurations can be done from the web interface.

The modification will allow you to add non-volatile memory to your router. I recommend using a SDcard up to 1GB. Some forum users reported that they got 2GB working, but both my 2GB cards failedto work. This might be solved in future with an updated MMC driver, but probably my SD cards are toblaim. The problem is that there are quite a number of incompatible 2GB cards around.

This modification might also work with MMC cards, but the used communication protocol(SPI) isoptional for MMC cards. It is only required for SD and mini-SD cards. So start with a SD card of1GB or less to confirm that everything is working. 1GB does perhaps not sound like a lot, but forthis application it is huge!

So what can you do with this added storage capacity:

Store your own custom programs, scripts and packages (standard oroptware)

Store communication and packet logs

Store your e-mail database for your e-mail server

Store your files for your web server

Store your files for your ftp server
http://www.dd-wrt.com/wiki/index.php/Buffalo_WHR-G54S_and_WHR-HP-G54_SD/MMC_modhttp://www.dd-wrt.com/wiki/index.php/Buffalo_WHR-G54S_and_WHR-HP-G54_SD/MMC_modhttp://en.wikipedia.org/wiki/Secure_Digital_cardhttp://en.wikipedia.org/wiki/MultiMediaCardhttp://www.dd-wrt.com/wiki/index.php/Optwarehttp://www.dd-wrt.com/wiki/index.php/Optwarehttp://www.dd-wrt.com/wiki/index.php/Buffalo_WHR-G54S_and_WHR-HP-G54_SD/MMC_modhttp://www.dd-wrt.com/wiki/index.php/Buffalo_WHR-G54S_and_WHR-HP-G54_SD/MMC_modhttp://en.wikipedia.org/wiki/Secure_Digital_cardhttp://en.wikipedia.org/wiki/MultiMediaCardhttp://www.dd-wrt.com/wiki/index.php/Optware


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Ground

Power, 3.3 volt

3 outputs (that are going to control the 3 inputs of the SD card)

1 input (that is going to read the data from the SD card output)

In fact we do not actually need to actively select the SD card via the Chip Select line. We can justalways select it by grounding the signal. So in that case we only need 2 outputs. Now let's get to it andopen our router to find what we need.

[edit] How to open your router

Check this Wiki How to open the Buffalo WHR-HP-G54 to see how to open a WHR-G54S or WHR-HP-G54 router without breaking it. Inside you will find a Printed Circuit Board (PCB).

Finding suitable IO points

Once you have opened the router you will have access to the PCB. We need to find several points on

the board that we are going to use to build our SD/MMC interface. To find these points we will needour general purpose friend, the multi-meter.

[edit] Finding Ground

It is very easy to find a grounded point, because ground is present all over the PCB. In most cases theinput power ground will also be the ground for the whole PCB. So start looking at the input powerconnector. This connector has quite big soldering pads, which makes it easy to add an extra wire. Oncethis point is found, verify it by checking big metal object on the PCB. Usually the metal housingaround the transmitter (see pictures below to find it) will be grounded too. To verify that the points areconnected use the conductivity check of the multi-meter. Make sure the router is powered down. The

connection between the points should give you a very low resistance, about the same resistance as whatyou would get when just shorting the multi-meter probes. With the Buffalo WHR-G54S I found that themetal mounting pins for the AOSS switch are also grounded(indicated with SD3/6 in the picturebelow). This gave me an easy ground access point, and is also a nice point for the routing of the wires.

[edit] Finding power, 3.3 volt

Once a grounded point is found we can start looking for the 3.3 volt power supply that we need. Checkyour power supply specification that is written on it. Check if it provides AC or DC at the output. Often

AC is indicated with a wavy line: ~. DC is indicated like this: . Verify the information on thepower supply with a multi-meter.

If the power supply output is 3.3 volt DC (WHR-G54S), then check the power socket connection at thePCB for 3.3 volt. To verify this you need to power up the router. Be very careful with this, as it is veryeasy to short circuit the board with some parts lying around. Switch the multi-meter to DC voltmeasurement, range 0-20 volt. The actual value that you find might be slightly higher or lower than 3.3volt(3.1-3.5 volt). If you power supply states an output voltage higher than 3.3 volt (WHR-HP-G54,+5v, others usually 5 or 12 volts) then the PCB contains a power regulator to lower the input voltage to3.3 volt DC. You will need to find this power converter, and it's 3.3 volt DC output. The powerconverter is a big component, usually close to the input power socket. Power up the router and connectone multimeter probe to a grounded point. Then carefully use the other probe to check the voltage at
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big pads of the big components close to the power socket until you find the 3.3 volt DC power supply.Below you can see what is printed on a WHR-G54S power supply. It states that it delivers 3.3 voltsDC, and maximal 2 amps. How convenient!

Image of a WHR-G54S Power Supply (a WHR-HP-G54 is different, supplying +5v).

[edit] Finding general IO output points

To control the SD card we need some outputs, which are connected to the inputs of the SD card.Routers usually contain LED's to signal their status. This gives us a easy opportunity to find someoutput points. The only disadvantage of this is that we will lose the signalling functionality of theLED's because they are now used for the SD card communication. What we first should establish iswhich LED's we can control by software. To do this login to the router and use the "gpio" command. Sounder Windows type in your dos box:

telnet

The default IP address is 192.168.1.1. Telnet needs to be enabled for this, which it is by default. Youcan enable or disabled it in the services tab of the web interface.

The login name is: "root", even if you changed the router name. The default password is "admin".

The syntax of the gpio command is like this:

gpio enable # to enable a IO pin, which switches the LED off

gpio disable # to disable a IO pin, which switches the LED on

gpio poll # to read the status of a switch

For the use numbers between 0 and 14. So watch the LED's closely while giving thegpio commands. You can also use this little command line to make your life easier:

while true; do gpio disable 1; sleep 3; gpio enable 1; sleep 3; done
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It will switch on the LED for 3 seconds, then switch if off for 3 seconds, and so on. You will need topress + "c" to exit from this command.

Replace the "1" in two places to change it for other IO pin numbers. In the screen capture below youcan see how it should look.

There is one important thing to consider! The IO pins can be used for input and for output purposes,and as you might know, there is usually a reset switch on a router. So what would happen if you writethe status of the pin that is used to see if the reset button was pressed!? Right, you create a reset. Youlose your settings as if you pressed the reset button. You will lose the telnet co

Documents

Draft2 Finalized Project Covac