Hallicrafters SR-150, Operation And Maintenance Manual

By Walter Cates WD0GOF (UPDATE 10/30/2013)  

3  

SUPPLEMENT TO SR-150  

OPERATION AND MAINTENANCE MANUAL  

TABLE OF CONTENTS 

INTRODUCTION .................................................................................................................................................................................... 2

1. SR-150 REFURBISHING AND REPAIRING ................................................................................................................................... 5

1-1. RECAPPING; ................................................................................................................................................................................. 5

1-2. RELAYS ........................................................................................................................................................................................ 5

1-3. AFTER MARKET MODIFICATIONS ......................................................................................................................................... 5

1-4. FACTORY UP-GRADES .............................................................................................................................................................. 6

1-5. INITIAL POWER UP .................................................................................................................................................................... 6

1-6. CHECK AND ADJUSTMENT OF OSCILLATORS: ................................................................................................................... 6

1-6-1. CARRIER OSCILLATOR: ...................................................................................................................................................... 7

1-6-2. HETERODYNE OSCILLATOR: ............................................................................................................................................. 7

1-6-3. VFO: The VFO is comprised of V9 and associated circuitry, VFO correction circuitry and the RIT/CAL circuitry. ............ 8

1-6-3-1. RIT/CAL ........................................................................................................................................................................................................ 8

1-6-3-2. VFO CORRECTOR ....................................................................................................................................................................................... 8

1-6-3-3. VFO ALIGNMENT ....................................................................................................................................................................................... 8

1-7. RECEIVER TESTING ................................................................................................................................................................... 9

1-8. RECEIVER FAULT ISOLATION ................................................................................................................................................. 9

1-8-1. EQUIPMENT REQUIRED: ................................................................................................................................................... 9

1-8-2. RX FAULT ISOLATION PROCEDURE: ............................................................................................................................... 9

1-8-2-1 RECEIVER TROUBLESHOOTING TABLE. ..................................................................................................................... 10

1-8-2-2 Final receiver test. ............................................................................................................................................................. 11

1-9. TRANSMITTER TESTING ......................................................................................................................................................... 12

1-9-1. TRANSMITTER TESTING EQUIPMENT REQUIRED ........................................................................................................ 12

1-9-2. TRANSMITTER TESTING PROCEDURE ........................................................................................................................... 12

1-9-3. TX DRIVE FAULT ISOLATION ........................................................................................................................................... 13

1-9-4. TX BIAS FAULT ................................................................................................................................................................... 14

2. PRODUCTION RUN UP-GRADES ................................................................................................................................................. 15

2-1. FACTORY REVISIONS PER BULLETIN 1962-2 ..................................................................................................................... 15

2-2. KEY CLICK MOD ....................................................................................................................................................................... 16

3. SUBSYSTEM TECHNICAL INFORMATION .............................................................................................................................. 17

3-1. RIG CLEANING .......................................................................................................................................................................... 17

3-1-1. CHASSIS CLEANING .......................................................................................................................................................... 17

3-1-2. TUBE SOCKET CLEANING KIT ......................................................................................................................................... 20

3-1-3. AIR VARIABLE CLEANING ................................................................................................................................................ 21

3-2. MICROPHONE SELECTION ..................................................................................................................................................... 22

3-3.VFO DRIFT................................................................................................................................................................................... 23

3-3-1. VFO DRIFT TEST ................................................................................................................................................................ 23

3-3-2. RIT ZENER MOD ................................................................................................................................................................. 23

3-4. SR SERIES RIT/CAL ADJ DISCUSSION .................................................................................................................................. 24

3-4-1. SSB RIT OPERATION .......................................................................................................................................................... 24

3-4-2. CW RIT OPERATION & THE SR-150. ................................................................................................................................ 25

3-5. RELAYS K2 & K3 ....................................................................................................................................................................... 26

3-5-1. K2 & K3 SUBSTRATE WARPING. ...................................................................................................................................... 26

3-5-2. K2 K3 CLEANING: .............................................................................................................................................................. 27

3-5-3. NON-STANDARD RELAY REPLACEMENT ....................................................................................................................... 27

3-5-4 K2 WIRING AND PIN OUT .................................................................................................................................................. 29

3-5-5 K3 WIRING AND PIN OUT .................................................................................................................................................. 30

3-6. PA LOADING COIL L32 ............................................................................................................................................................ 31

3-7. RECEIVER GAIN IMPROVEMENT.......................................................................................................................................... 32

3-8. RX GAIN ANOMALY ................................................................................................................................................................ 32

3-9. MIC GAIN AND AUDIO OSCILLATIONS IN THE SR-150 .................................................................................................... 34