Understanding Repeater Understanding Repeater OperationsOperations

Presented by:Presented by:

The Cheshire The Cheshire County DX County DX Amateur Radio Amateur Radio ClubClub

AD1TAD1T

Understanding Repeater Understanding Repeater OperationsOperations

Designed by:Designed by:Joel HuntleyJoel Huntley

WA1ZYXWA1ZYX

Areas to be Areas to be DiscussedDiscussed

Simplex Simplex OperationsOperations

Input FrequencyInput Frequency DuplexerDuplexer ControllerController Hang - TimeHang - Time Courtesy Beep or Courtesy Beep or

MsgMsg OffsetsOffsets

Duplex OperationsDuplex Operations Output FrequencyOutput Frequency CTCSS / PL / CGCTCSS / PL / CG Ancillary FunctionsAncillary Functions Time-Out TimerTime-Out Timer AutopatchAutopatch Operating PracticesOperating Practices

Simplex Simplex OperationsOperations

Refers to operations involving Refers to operations involving ONEONE RF Carrier Frequency.RF Carrier Frequency.

Transmit Transmit OROR Receive, one at a time Receive, one at a time

Typical Radio User operates in this Typical Radio User operates in this modemode

Duplex OperationDuplex Operation Transmitting Transmitting ANDAND Receiving at the Receiving at the

same time Using same time Using TWOTWO Different RF Different RF Frequencies.Frequencies.

Typical Repeater Station operates Typical Repeater Station operates in this mode.in this mode.

Duplex Duplex OperationsOperations

Input FrequencyInput Frequency• Repeater Receives on this FrequencyRepeater Receives on this Frequency• User Transmits on this FrequencyUser Transmits on this Frequency

Output FrequencyOutput Frequency• Repeater Transmits on this Repeater Transmits on this

FrequencyFrequency• User Receives on this FrequencyUser Receives on this Frequency

Duplex Duplex OperationsOperations

The The DifferenceDifference in Frequency between in Frequency between InputInput & & Output Output is called the is called the OFFSET OFFSET..

OffsetOffset is referenced to the Repeaters is referenced to the Repeaters OutputOutput Frequency. Frequency.• Example: 443.800 Mhz Repeater Example: 443.800 Mhz Repeater

OutputOutput• 448.800 Mhz Repeater 448.800 Mhz Repeater

InputInput• Equals +5.000 Mhz Equals +5.000 Mhz OFFSETOFFSET

10 Meter Offset10 Meter Offset-100 Khz-100 Khz

OutputOutput 29.620 Mhz 29.620 Mhz Input Input 29.520 Mhz 29.520 Mhz Offset Offset - .100 Khz - .100 Khz

• Must be Must be GENERAL ClassGENERAL Class or Above! or Above!

6 Meter Offset6 Meter Offset-1.00 Mhz-1.00 Mhz

OutputOutput 53.090 Mhz 53.090 Mhz Input Input 52.090 Mhz 52.090 Mhz Offset Offset - 1.000 Mhz - 1.000 Mhz

2 Meter Offset2 Meter Offset- OR + .600 Khz- OR + .600 Khz

•Depends on OutputDepends on Output

OutputOutput 146.805 Mhz 147.030 Mhz 146.805 Mhz 147.030 Mhz Input Input 146.205 Mhz 147.630 Mhz 146.205 Mhz 147.630 Mhz Offset Offset - .600 Khz + .600 - .600 Khz + .600

KhzKhz

1.25 Meter Offset1.25 Meter Offset 220 Band 220 Band

- 1.600 Mhz- 1.600 Mhz

OutputOutput 224.720 Mhz 224.720 Mhz Input Input 223.120 Mhz 223.120 Mhz Offset Offset - 1.600 Mhz - 1.600 Mhz

70 Centimeter Offset70 Centimeter Offset440 Band440 Band

- OR + 5.00 Mhz- OR + 5.00 Mhz• Depends on Depends on OutputOutput

OutputOutput 443.800 Mhz 449.875 Mhz 443.800 Mhz 449.875 Mhz Input Input 448.800 Mhz 444.875 Mhz 448.800 Mhz 444.875 Mhz Offset Offset + 5.000 Mhz - 5.000 + 5.000 Mhz - 5.000

MhzMhz

2 Meter Bandplan2 Meter Bandplan

The 144 to 148 Mhz Amateur Radio 2 The 144 to 148 Mhz Amateur Radio 2 Meter band plan.Meter band plan.

How to Locate How to Locate RepeatersRepeaters

Repeater Directory is Repeater Directory is divided First by Band, divided First by Band, then State, then by then State, then by Region - North, Region - North, South, Central etc, South, Central etc, then by actual then by actual location.location.

DuplexersDuplexers

Allows Repeater to Transmit & Receive Allows Repeater to Transmit & Receive at the same time on ONE Antennaat the same time on ONE Antenna

To Rec From XmtrAntenna

Types of Repeater Types of Repeater AntennasAntennas

Commercial Commercial Grade Grade Repeater Repeater Antennas.Antennas.

Folded Dipole Folded Dipole Style.Style.• Can be Can be

configured for configured for Omni or Omni or Directivity.Directivity.

StationMaster, StationMaster, Fiberglass StyleFiberglass Style

FeedlinesFeedlines Most Repeaters use Most Repeaters use

Commercial Grade Commercial Grade antenna feedlines.antenna feedlines.

Higher Frequencies Higher Frequencies and long runs for high and long runs for high towers mean huge towers mean huge signal losses with signal losses with cheap cable.cheap cable.

Larger cable, lower Larger cable, lower losses.losses.

Andrews or Cablewave7/8” Foam

More on More on AntennasAntennas

No “Ringo’s” or Flimsy Antennas No “Ringo’s” or Flimsy Antennas should be used on High Mountain should be used on High Mountain Top Installations!Top Installations!

Need to be RUGGED!!Need to be RUGGED!!

And Here’s Why……………...And Here’s Why……………...

Severe Ice Build-UpSevere Ice Build-Up Top Top

of of Mtn Mtn After After Ice Ice StorStormm

ControllerController

Interfaces the Receiver by providing Logic and Interfaces the Receiver by providing Logic and Audio to the Transmitter.Audio to the Transmitter.

Provides Automatic ID of RepeaterProvides Automatic ID of Repeater Provides Timers, Messages and other FunctionsProvides Timers, Messages and other Functions

TimersTimers Hang / Tail TimerHang / Tail Timer

• Amount of Time the Repeater Transmitter Amount of Time the Repeater Transmitter stays on-the-air after User Stops Transmitting.stays on-the-air after User Stops Transmitting.

Courtesy TimerCourtesy Timer• Time between User end of transmission and Time between User end of transmission and

Courtesy “Reset” beep.Courtesy “Reset” beep. Time-Out-TimerTime-Out-Timer

• Amount of time before Repeater Transmitter Amount of time before Repeater Transmitter shuts off. Usually about 3 minutes.shuts off. Usually about 3 minutes.

Courtesy Courtesy MessageMessage

Tells the User when the Time-Out-Tells the User when the Time-Out-Timer has reset.Timer has reset.• Usually after a slight delay to allow for Usually after a slight delay to allow for

other stations to break inother stations to break in.. If a User begins Transmitting Prior to If a User begins Transmitting Prior to

the Courtesy Message, Previous Users the Courtesy Message, Previous Users Time is added to your Time.Time is added to your Time.• After 3 minutes, Repeater will “Time-After 3 minutes, Repeater will “Time-

Out”.Out”.

AutopatchAutopatch Additional Function of the Controller Additional Function of the Controller

that interfaces the Repeater to the that interfaces the Repeater to the Telephone System.Telephone System.

No business calls allowed.No business calls allowed.• Although because of deregulation, some Although because of deregulation, some

“commercial” type calls are allowed “commercial” type calls are allowed now.now.

• Ultimately, it’s up to each Repeater Ultimately, it’s up to each Repeater Owner/Trustee. Ask first.Owner/Trustee. Ask first.

Autopatch Do’s & Autopatch Do’s & Don’tsDon’ts

DODO Always ID your station prior to use. Always ID your station prior to use. DODO Limit Autopatch Use to Necessary Limit Autopatch Use to Necessary

calls only.calls only.• Use Phone Use Phone BEFOREBEFORE you leave the Office. you leave the Office.

DON’TDON’T Use Autopatch to avoid a Toll Use Autopatch to avoid a Toll Call!Call!• Remember, Somebody’s paying for that Remember, Somebody’s paying for that

Phone Line. Ma Bell Doesn’t give those Phone Line. Ma Bell Doesn’t give those away to anybody!!!away to anybody!!!

CTCSS / PL / CGCTCSS / PL / CG CTCSSCTCSS = = CContinuous ontinuous TTone one CCoded oded SSquelch quelch SSystemystem

• PLPL = = P Private rivate LLine “Motorola’s Trade Nameine “Motorola’s Trade Name• CGCG = = CChannel hannel GGuard “General Electric’s Trade Nameuard “General Electric’s Trade Name

Sub-Audible Tone, superimposed on a Sub-Audible Tone, superimposed on a Transmitted Signal to open a Receivers Squelch.Transmitted Signal to open a Receivers Squelch.

If a Receiver hears a Signal With the Correct If a Receiver hears a Signal With the Correct Frequency Frequency CTCSSCTCSS Tone, Squelch Opens, Tone, Squelch Opens, otherwise it ignores the signal.otherwise it ignores the signal.

CTCSS / PL / CGCTCSS / PL / CG In Repeater Early days, “In Repeater Early days, “PLPL” was used to ” was used to

keep stations out - ie, “Closed” Repeater. keep stations out - ie, “Closed” Repeater. Available to members only.Available to members only.

Now, because there are so many repeaters, Now, because there are so many repeaters, and frequency pairs are becoming scarce, and frequency pairs are becoming scarce, ““PLPL” allows a user to “Select” which ” allows a user to “Select” which Repeater one brings up in overlapping Repeater one brings up in overlapping areas.areas.

Also Used to keep Interference out of Also Used to keep Interference out of Repeater.Repeater.

Ancillary Ancillary FunctionsFunctions

Other Functions provided by a Repeater Other Functions provided by a Repeater might be Linking to other Repeaters for might be Linking to other Repeaters for “Wide Area” Coverage.“Wide Area” Coverage.

Severe Weather Alerting.Severe Weather Alerting.

Block DiagramBlock DiagramAntenna

Duplexers

Controller

ReceiverInput

448.800

TransmitterOutput443.800

Power Supply

Finished ProductFinished Product

The End Result After The End Result After

Putting It All Together!Putting It All Together!

UHF Motorola Micor Keene UHF Motorola Micor Keene RepeaterRepeater

443.800 MHz 141.3 PL443.800 MHz 141.3 PL

Power Amp

Transmitter

Audio & Squelch

Receiver

Power Supply

Duplexers

Controller

Operating Operating PracticesPractices

Speak in Speak in PLAINPLAIN LanguageLanguage

Remember, Don’t Remember, Don’t give a user a give a user a Signal Strength Signal Strength report on a report on a Repeater. Repeater. YOU YOU ARE REPORTING ARE REPORTING the REPEATERS the REPEATERS STRENGTHSTRENGTH!!!!

Use Normal Use Normal Words!!!!Words!!!!

DestinatedDestinated? What ? What “is” that word…..“is” that word…..

HandleHandle? I have ? I have no Idea - What’s no Idea - What’s your name?your name?

Break 19Break 19 -- -- Nope, Nope, I don’t Think SoI don’t Think So!!!!!!

Finances Finances RequiredRequired

RepeaterRepeater 1-2K, if actual Repeater. Probably 1-2K, if actual Repeater. Probably less if a converted mobile unit.less if a converted mobile unit.

DuplexerDuplexer $500 and up depending on Band. $500 and up depending on Band. AntennaAntenna $300 - $1000, Again depending on $300 - $1000, Again depending on

Band / StyleBand / Style FeedlineFeedline $3 to $6 per Foot Typical for Heliax. $3 to $6 per Foot Typical for Heliax. ConnectorsConnectors for Heliax $60 - $80 each, 2 req. for Heliax $60 - $80 each, 2 req. ControllerController $500 - 1K Depending on Features $500 - 1K Depending on Features

The EndThe End If you have any If you have any

questions….. questions….. Contact:Contact:

Joel , WA1ZYX atJoel , WA1ZYX at jhuntley@keene.ejhuntley@keene.e

dudu

December 1998