THETHE K5RWK K5RWK

REPEATER REPEATER

HOW IT WORKS

By F Cummings, W5LQU

August 2009

OUR REPEATER BLOCK DIAGRAMOUR REPEATER BLOCK DIAGRAM

THE PRESENT RWK REPEATERTHE PRESENT RWK REPEATER

BACK OF OUR REPEATERBACK OF OUR REPEATER

THE REPEATERTHE REPEATER

INSIDE THE REPEATERINSIDE THE REPEATER

PROGRAMMING THE REPEATERPROGRAMMING THE REPEATER

The repeater is programmed using a PCThere are 8 possible channels we set up 4Set RX and TX frequenciesSet timers for hang time and time outSet TX power out and RX squelchSet CTCSS tones if needed for TX and RX

PROGRAMMIMG THE REPEATERPROGRAMMIMG THE REPEATER

THE CONTROLLERTHE CONTROLLER

THE CONTROLLER CIRCUIT BOARDTHE CONTROLLER CIRCUIT BOARD

PROGRAMMING THE CONTROLLERPROGRAMMING THE CONTROLLER

The controller is programmed using DTMF tones through the RX

Set various control operator functionsSet the normal voice ID and CW IDSet timers for hang time and time outSet the time out messageSet the courtesy tones

TROUBLE SHOOTINGTROUBLE SHOOTING

2M DB2242M DB224ANTENNAANTENNA

A DB224 antenna with4 vertically stacked folded dipoles whichcan be connected to form an omni or eliptical pattern withabout 6 to 8 dB gain

OUR PRESENT ANTENNAOUR PRESENT ANTENNA

OUR NEW LOCATIONOUR NEW LOCATION

VIEW FROM THE NEW SITEVIEW FROM THE NEW SITE

LIGHTNING PROTECTION LIGHTNING PROTECTION and 2m / 440 DUPLEXERand 2m / 440 DUPLEXER

THE THE BIGBIG PROBLEM PROBLEM

Connecting the TX / RX to the same antenna at the same time

2m / 440 dual band radiosCollinear verticalsDelta of 147.72/147.12 = 0.4 %Need a very special Duplexer for 2m

repeatersCombination bandpass/bandreject circuitRequires very high Q circuits

RWK DUPLEXERRWK DUPLEXER

BP/BR vs LP/HP6 quarter wave cavities – 3 TX and 3 RX1 BP and two BP/notch cavities eachRX bandpass 147.72 and notch 147.12

MHzTX bandpass 147.12 and notch 147.72

MHzAbout 95 dB isolation from BP to notch

each

DUPLEXER RESPONSE CURVESDUPLEXER RESPONSE CURVES

Tx

AD5VO TUNING THE DUPLEXERAD5VO TUNING THE DUPLEXER

RWK 6 CAVITY DUPLEXERRWK 6 CAVITY DUPLEXER

THE K5RWK REPEATERTHE K5RWK REPEATER