MFJ MFJ-662 User Manual

Table of Contents
Introduction ..........................................................................................................	1
How Your MFJ-662 Simplex Repeater Works.....................................................	1
Jacks and Controls................................................................................................	2
Specifications .......................................................................................................	2
Power Sources ......................................................................................................	3
Interface Connections...........................................................................................	4
Set-up Testing and Operation...............................................................................	4
Selecting a PTT Interface.....................................................................................	6
Record Level ........................................................................................................	6
Transmit Level .....................................................................................................	7
Simplex Repeater Operating Tips.........................................................................	7
Repeater Set-Up Suggestions ...............................................................................	8
Theory of Operation .............................................................................................	9
In Case of Difficulty.............................................................................................	9
Technical Assistance ..........................................................................................	10
Schematic ...........................................................................................................	11

MFJ-662 Instruction Manual

Simplex Pocket Repeater

INTRODUCTION

Congratulations on purchasing the MFJ-662 Simplex Pocket Repeater. This small unit houses everything you need to turn your HT, mobile, or base-station radio into a range-extending simplex repeater system. The MFJ-662 may be small, but it's loaded with high-tech features:

32-Second Memory: Captures your entire message with time to spare.

PIC Controller: Reliable PIC technology manages each function flawlessly.

Adjustable Gain: Programmable transmit level ensures best audio quality.

Selectable PTT Interface: Keys load-sensing or ground-contact PTT circuits.

Small Size: Ultra-compact pocket-sized case fits anywhere.

Flexible Power: Uses single 9V battery or any external 9-15 Vdc source.

Versatile Interface: Open-ended patch cable adapts to virtually any radio.

Courtesy Tone: Controller signals the end of repeated messages.

HOW YOUR MFJ-662 SIMPLEX REPEATER WORKS

Repeater stations extend communication range beyond line-of-sight by intercepting and re-transmitting signals from a favorable location. Repeaters may be either duplex or simplex in design. Most Hams are more familiar with the sophisticated duplex systems set up by repeater groups to expand mobile communication. These repeaters occupy two channels, one for listening and one for simultaneously re-transmitting. Duplexing offers the convenience of realtime conversation, but the hardware is generally too large and complex to move around for portable use.

Duplex Repeater Station

Station	Receiver		Simplex Repeater Station
		Control
Antenna
	Controller	Link	MFJ-662	Portable
		Auto-	Simplex
duplexer	Transmitter	patch	Controller	HT
Tower
	Amplifier	Telco		Rock
	Power	Line
	Supply

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MFJ-662 Instruction Manual

Simplex Pocket Repeater

Unlike duplex systems, simplex repeaters require only a portable transceiver and a self-powered controller such as your MFJ-662. They occupy a single channel and use solid-state voice-memory to record and then repeat each incoming transmission. Simplex repeaters are especially useful for increasing the range of hand-held HTs and mobile units participating in field activities such as races, missing-person searches, hunting trips, disaster communication, and special events. All you need is an accessible elevated location and a minute or two of time to place your repeater in service.

JACKS AND CONTROLS

		3
		Rec
	RADIO		PWR
1			MFJ-662 4
	INTERFACE	2

1.Interface Jack: Accepts 5-pin IDC plug for Mic, Record Audio, PTT lines and ground.

2.Record Indicator: LED illuminates when controller is recording.

3.Power Off/On: Applies power to controller from internal battery or external jack.

4.External Power: Accepts 2.1-mm plug (9-15 Vdc source), disconnects battery.

SPECIFICATIONS

Power Source ..........................	9V battery or 9-15 Vdc supply
Current Drain ..........................	3.5 mA Standby
PTT Mode ..............................	Selectable (ground-contact or load-sensing)
Voice Memory ........................	32 Seconds total storage
Dimensions .............................	2.3" x 1" x 3.7"
Weight ....................................	≈ 2 oz.

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