Kenwood_T-599_bulletin.txt

Service bulletin no. 7 (2-11-1977)

No ALC - Drive 10 meters: Check for loose contact at oscillator wafer on coil pack.

No TX any band: Check the T1 on generator board (X52-0009-00).

No TX: Bad driver FET Q1 3SK22(GR) on X47-0004-00).

No relay action when TX: Bad Q8 2SA562(Y). When replacing Q8 change resistor R16 to 4.7 ohm.

Rubber belt sliping on drive and load: TKC has Chain Modification Kit.

No drive when shock: Check for loose output terminals af final rotary switch (S10-1002-05).

No output on any band: Check T2 GEN unit (X42-0009-00).

No TX: Check final relay for burned contacts. (S51-4017-15).

Bias current too high and blows fuse: Check for bad 6-7001A and shorted cathode resistors 10 ohm.

Cannot neutralize: Make sure shield is properly installed on driver 12BY7.

No output from generator unit (X52-0009-00): Bad Q4 TA7045.

No 9 Volt out at AVR (X43-0010-00): CHeck Q1 2SA606(L).

Low output power: If American 12BY7 is used in driver circuit, this can cause parasitic oscillation. Please use standard Kenwood replacement tubes.

Blows fuse: Check for shorted electrlytics at power supply (X43-0011-00).

AC hum on SSB transmission: Send for TKC bulletin.

1agina p