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The Open Feedline
M.A.R.A.
MICHIGAN
AMATEUR RADIO
ALLIANCE
Inside this issue
Antennas & Burritos .................... 1
Repeater & C4FM Wires-X .......... 2
Hamvention & GLHamCon .......... 3
Local Hamswaps .......................... 4
Membership Information ............ 5
On Ground Antenna Article…...6-9
MI QSO Party…..……………………..10
After Christmas Party…………...11
S pringtime in Michigan is the time for yardwork, gardens, and of course, new
antennas, towers, etc. I have noted that several of our club members have start-
ed experimenting with new antennas for the low bands, even though the low
band propagation up ’till now is pretty much lousy this year. Let’s hope for improvement as
time progresses. (See more on antennas later in the newsletter)
Several random notes about those new antenna experiments:
One, in most cases (not all) height of the feed points makes a big difference as well as the
Hight of the non-feed ends. This is especially true of most dipoles and inverted “V” anten-
nas. (slopers included...think half-dipole)
Two, and very important, is the cut for and resonant frequency of the antenna. No matter
what form the antenna takes, and you can bring the SWR to 1:1 with an antenna tuner… if it
ain’t resonant on the transmit frequency, it likely ain’t going to “get out”. In this case reso-
nance is the key factor.
As a hint, check the antenna without the tuner and see where the lowest natural (resonant)
frequency is, then trim to your desired frequency . A quick way to do this without clipping
the ends prematurely and find you cut too short, is to fold the ends back on themselves
until you find that sweet spot. Remember most dipoles “freak out” if the legs are not exact
lengths of each other. (Except, of course, off center fed windoms where the calculations
need to be exact)
In any event, be safe this spring/summer, stay way from powerlines, and follow safe prac-
tice procedures on ladders.
Dinner Parties and Upcoming Burrito Nite!
MARA held the annual After Christmas Party on Jan 21st, 2017 The menu included Swiss
Steak, chicken, and other delights along with a desert table. Pictures are on the picture
page near the end of this newsletter. Speaking of Dinner, another Burrito Nite is upon us
Friday night, April 28th at the 5th St Hall, 701 5th Street, Grand Rapids. Come one come all
to a great night of Ham radio fellowship and enjoy the N8NIJ burritos! We are always look-
ing for kitchen volunteers, just contact Dan, N8NIJ, otherwise see you anytime after 6pm for
“Burrito Nite” Open to all, so bring you friends.
5th Street Hall
701 5th Street
Grand Rapids
M.A.R.A. Newsletter Volume 26 Issue 2 Spring 2017
Page 1 of 11
Current Net Director is Larry Dells, KD8KVR. You can usually find Larry on the MARA Repeater: 145.230 Mhz, -600 PL 94.8
MARA Repeater News W8USA
Next MARA Meeting—Wednesday, May 10, 2017 Plainfield Township Fire Department Training Center—5 Mile
The MARA Repeater, W8USA now is run-
ning smoothly with a new controller that is
more in line with our repeater’s capabili-
ties. As we slowly get acquainted with this
new controller we will begin adding more
capabilities. First up will be again con-
necting to the ethernet link. Eithernet is
currently offline as we determine the con-
troller’s characteristics.
WIRES-X
Just by accessing the W8USA WIRES-X node
using a C4FM digital transceiver, you can
enjoy the C4FM digital communications
such as the high-quality QSO and news
function with stations located far away
including overseas stations via the Internet
as shown in the illustration below. Using a
C4FM digital transceiver enables a very
simple access operation. Currently the
actual Node resides at the home of KC8KVR
and is accessed through the repeater. As
of this time, Wires-X is only accessed by the
following Radios: Yaesu FTM-3200, Yaesu
FTM-400XD, Yaesu FT-1XDR, Yaesu FT-2DR,
Yaesu FT-991. We will keep you informed
Page 2 of 11
Ham Radio Swaps.
From WB8R Section Manager The largest planned ham gather-ing in Michigan is still in the plan-ning process but is gathering significant steam as we move closer to the actual event. The Great Lakes HamCon will take place at Michigan International Speedway located in the beauti-ful Irish Hills of Southeast Michi-gan on October 7 & 8, 2017. We do have some breaking news in that our event has been desig-nated as the Great Lakes ARRL Division Convention and that the ARRL President Rick Roderick, K5UR will be attending our event to represent the ARRL. We now have 16 amateur radio clubs who are founding mem-bers of the Great Lakes Amateur Radio Association, the parent organization of Great Lakes HamCon. Those clubs are (in no particular order): Oakland Coun-ty ARS, MI QRP Club, Branch County ARC, Central MI ARC, Arrow Communication Assn, Southern MI ARS, Cascades ARS, Livingston ARK, Hillsdale County ARC, South Lyon AARC, General Motors ARC, Livonia ARC, Monroe County Radio Communications Assn, Adrian ARC, Motor City Radio Club, and Utica-Shelby Emergen-cy Communications Assn. We are grateful to these clubs for seeing the vision and for stepping forward to provide the support and funding that is nec-essary to make this event a reality.
Larry Camp, WB8R
MI Section Manager, ARRL
Mark Your Calendars!
Hamvention will be held at the Greene County Fairgrounds and
Expo Center Xenia, OH. For more information, please select the tabs
below or use the navigation menu above to visit pages of interest. If you have a
specific question that isn’t answered on the site, please contact us.
The entire staff of Hamvention volunteers is working hard behind the scenes to
make 2017 a year to remember as we complete the transition from the old Hara
Arena location to Hamvention’s new home at the Greene County Fairgrounds
and Exposition Center. Details will be posted when they become available, so
check back often. In the meantime, enjoy this photo tour of Hamvention’s new
The newest major ham-fest in our region will de-but October 7/8, 2017 at Michigan International Speedway. The Great Lakes Ham Convention, GLHamCon for short, aims to be one of the biggest and best ama-teur radio gatherings in the country. Watch this space as our prepara-tions for the “green flag” continue!
Questions? Ideas? Write
to info(at)glhamcon.org.
Page 3 of 11
Michigan Hamfest Closer than Dayton!
Hamvention 2017—May 19, 20 and 21
Date: 05/06/2017
Location: Cadillac, MI Type: ARRL Hamfest
Sponsor: Wexaukee Amateur Radio Club
Website: http://www.wexaukeearc.org
Date: 07/29/2017
Location: Lansing, MI Type: ARRL Hamfest
Sponsor: Central Michigan
Amateur Radio Club
Website: http://
www.centralmiarc.com/
outdoorhamfest.php
Cadillac Amateur Radio & Computer Swap
CMARC “Outdoor” Hamfest
Date: 06/02/2017
Location: Hudsonville, MI Type: ARRL Hamfest
Sponsor: Independent Repeater Association
Website: http://w8ira.org
IRA Hamfest
GRA Hamfest
Date: 09/09/2017
Location: Wyoming, MI Type: ARRL Hamfest
Sponsor: Grand Rapids Amateur Radio Association
Website: http://w8dc.org
Page 4 of 11
This month we are featuring a nice receive antenna article and
plans courtesy of Mike Hood, KD8JB. For those of you that
want a quieter receive antenna and have ground space to put
the antenna, this article is for you. The beauty of this antenna
is that it can be of any length. Mike told me he used 50 feet
on each leg, and any length feedline. You can use any lengths
you have on hand with good results. I would suspect it will
work best if both legs are the same length, but experiment
and let us know what success you have. The low bands are
not in the best of shape as this is being written, so any noise
you can eliminate with a quieter antenna should be worth it.
M.A.R.A
Michigan Amateur Radio Alliance
MARA holds their weekly 2-meter
Net, every Thursday, at 8 PM on the
MARA W8USA repeater, 145.230
MHz -600Khz PL. 94.8. MARA holds
their monthly meetings on the 2nd
Wednesday of the month at 7:30PM,
at the Plainfield Township Fire Dept.
Training Building, located on the SW
corner of 5 Mile RD and Plainfield
Ave NE, in Grand Rapids. This site
ishandicap accessible. All are wel-
come to attend our meetings
M.A.R.A
Michigan Amateur Radio Alliance
MARA
P.O.Box 670
Comstock Park MI 49321-0670
Webmaster ERIN AMMONS KD8NSU
Newsletter Editor PAUL HUMMEL
K9BOJ [email protected]
Write us by contacting our
Webmaster or log into W8USA.Org
and send your message from the
home page to the Webmaster.
Annual dues to MARA are $20.
Family memberships are an additional $5.
Persons aged 70 and over - $20.00.
Membership is free to students under 21.
Memberships expire on December 31st, and
club dues are due on January 1st.
MARA membership is open to all interested
persons. Please send change of address
information and membership applications to the
club secretary.
M.A.R.A. Membership Information
Page 5 of 11
The On Ground, Distributed Capacitance, Terminated Dipole Antenna* By Mike Hood, KD8JB
Acronym TBD** . The antenna described here is unique in the sense that it is intended for receiving only. This
makes it a fine monitor antenna for your transmissions or a great BCB antenna for MW DX. That said, I have not
tried transmitting with this antenna, and it may indeed work for transmitting, particularly at low power. If you try
it for transmitting, let me know your results.
SWR –Just because you’re gonna ask. Curiosity overwhelmed me too, as to what the SWR might be on this antenna. These readings were taken after
the antenna was deployed. I was surprised by the results. These measurements roughly correspond to the SWR
points on the left meter on an MFJ-259 antenna analyzer.
SWR Frequency
(MHz)
Resistance
(Ohms)
R X
2.50 4.734 40 22 25
2.00 5.151 30 25 9
1.70 5.426 32 29 3
1.50 5.650 39 34 7
1.20 5.920 45 41 6
1.10 6.068 48 44 6
1.10 6.502 45 44 6
1.20 6.537 45 42 6
1.50 6.960 38 33 4
1.70 7.241 32 29 4
2.00 7.562 32 27 13
2.50 8.106 45 28 34
Note the
range in the
Resistance.
This is con-
sistent with
the parallel
75Ω termi-
nating resis-
tors, one at
the end of
each dipole
leg.
Page 6 of 11
CONSTRUCTION Building this antenna is straight forward. It’s basically a center fed dipole with a standard coaxial feedline. At
that point, similarities to a “normal” dipole end. Refer to the breakdown in Figure 1 and the Materials Required
list below to get started.
Materials Required (All plastic pipe parts are ½” PVC Schedule 40 pipe. Cut the pieces to the lengths indicated in
the table.):
Figure 1
Index No. Description Qty Notes
1 ½” End Cap, Drilled 5 See text for hole sizes.
2 2-1/2” Nipple 4
3 ½” Tee 1
4 Dipole Legs, Coaxial Cable 2 Any length.
5 Feedline, Coaxial Cable 1 Any length.
6 5” Nipple 1
7 ½” End Cap, Undrilled 2
8 Resistor, 75 Ohm, 2 Watt, Carbon
Composition
2 Not shown. See text.
--- Electricians’ Tape, F-4 Tape, and or
Liquid Tape
A/R
--- Solder, Rosin Core A/R
--- Soldering Flux A/R Your choice of liquid or paste.
--- PVC Primer A/R
--- PVC Cement A/R
Page 7 of 11
Refer to Figure 1 for the follow-
ing procedures.
Preliminary Steps:
1-Drill the appropriate sized
holes in 5 End Caps, using the
table above, as a guide.
2-Brush cement primer where
each PVC part will mate with
another PVC part.
3-Determine how much coaxial
cable you’re willing to use in the
dipole portion of the antenna.
4- Locate the center of the coax-
ial cable and cut it at that point.
You should have two pieces of
coax that are equal lengths.
5- Determine how much coaxial cable you’re willing to use for the feedline. NOTE: The feedline should be
all one piece, not broken up with connectors and the like. Remember, this antenna is on the ground
and subject to all manner of crud getting into any connector.
6- Slip the coaxial cable through the holes in the 5 End Caps. Make sure you orient the end caps correctly.
Each dipole leg should have 2 End Caps. The feedline will have 1 End Cap. Again, refer to Figure 1.
T-section Assembly:
7-Strip 1-1/2” of the insulation from all ends of the coaxial cable dipoles, and one end of the feedline.
8- Thread the dipole coaxial cable ends intended for the T-section through the appropriate nipples and into
the outer ends of the Tee.
9- Pull the cables through the center opening of the Tee to about 4” to give you a little room to work.
10- Thread the feedline coaxial cable end intended for the T-section through the 6” nipple about 4”.
11- Prepare the ends of the dipole and the feed line end intended for the T-section in a manner you usually
use to separate the center conductors from the shields. See Figure 2.
Hole sizes for End Caps depending upon coax used:
Coaxial Ca-ble Type
Hole Size
(Inches)
Drill Sizes
Fraction Letter/Number
RG-58 (All) 0.195 3/16 to 13/64 9
RG-59 0.242 15/64 to ¼ C (Exact)
RG-6 0.332 21/64 to 11/32 Q (Exact)
RG-62 0.242 15/64 to ¼ C (Exact)
RG-8X 0.242 15/64 to ¼ C (Exact)
Figure 2
Page 8 of 11
12- Solder the shields of the dipole ends to the cen-
ter conductor of the feedline.
13- Similarly, solder the center conductors of the
dipole ends to the shield of the feedline.
14- Isolate and insulate the connections from step
12 and step 13 with some sort of tape. (See
parts list.). See Figure 3.
While a tie-wrap is not included in the parts list, illus-
trations, or my antenna, a small tie-wrap securing the
two dipole legs together in the T-section will improve
the integrity of the soldered connections and keep the
dipole sections from being pulled out. A second tie-
wrap at the insulation of the feedline and the shield
would help to keep the feedline from being pulled out
in the event of someone tripping over it while it is lying
on the ground. If you elect to do this, do it before step
15.
15- Cement all the parts for the T-section with the
end result as shown in Figure 4.
End Assemblies (No illustration. Sorry. Use your imagination.):
Thread coaxial cable through 1 drilled End Cap (this should have been done in step 6, but you may have
overlooked this or the cap has fallen off the cable. Make it right.)
Lay the 75Ω-2W resistor against the center conductor insulation and wrap the two together with electri-
cian’s tape.
Solder one end of the resistor to the coaxial cable shield and the other end to the center conductor. There is
no need to tape this connection, but if you have liquid tape, applying it here will aid in maintaining a
weatherproof connection.
Cement all the parts for the end assembly as shown in Figure 1.
Perform steps 16 through 19 for the other end of the dipole.
Figure 4
Figure 3
Page 9 of 11
Join the fun! Next big M.A.R.A. Operating event will be the 2017 Field Day, June 24-25 at the Madison Square Gun Club Grounds. More at the May and June Meetings!
Michigan QSO Party W8USA
Next MARA Meeting—Wednesday, May 10, 2017 Plainfield Township Fire Department Training Center—5 Mile and Plainfield Avenue
Larry KC8KVR hosted the
QSO party, Jerry W8MSK
one of the fastest keyers in
the state did a fantastic job
as always, (working two
contacts at a time on cw.)
Dan N8NIJ and Corey
KD8SZZ logging and working
ssb, Mike K8OOK ssb and
code. Mike found my prac-
tice key and did 20 wpm
while holding the key down
with one hand and keying
with the other. Plenty of
snacks on hand and a great
time.
Page 10 of 11
Larry, KC8KVR working MI QSO Party Jerry, W8MSK operates CW at MI-QSO Party
Mike, K8OOK taking to the mic on the
SSB portion of the Michigan QSO Party
Mike, K8OOK making use of a found
practice key at the MI QSO party.
The MARA After Christmas Annual Dinner Party was held on January 29 this year at the 5th
Street Hall in Grand Rapids. A fun time with a buffet dinner prepared by "That Polish Girl"
Catering Service. All in attendance seemed to agree that this year's outing was a great suc-
cess with an outstanding dinner. Jerry Wittkoski, W8MSK held the winning number in the
annual 50/50 drawing.
Page 11 of 11
