2017年12月2日 · It works OK on 80, 40, and 20 meters - both transmit and receive. It does not work at all on 15, and 10 meters. It will not receive or transmit, nor does the digital display show any numbers, just two decimal dots. That is what I will be trying to repair, and I think I have a good idea (after some initial research) what is wrong.

TS-120S Repair Notes. Symptom Repair; General Problems; Analog Dial Calibration Off: Mechanical adjustment: Loss of Digital Display: Check P5/J5 on Carrier Unit: Power on Meter Max: ... High IC in RX: Bad finals: 28.5 HF Oscillation: Tighten ground screws at Relay unit X41-1250 (see SB-844)

2020年4月11日 · I think I've seen the same problem in a TS-120 before (certainly on TS-130 / TS-430 and other radios of the 80s & 90s): PIN switching diodes fail with high reverse leakage, which brings the whole control line up/down and might also impact other (apparently unrelated) areas (LPF control, TX/RX switching etc).

2022年5月14日 · Hello all, I recently came across a TS-120S that is breaking into uncontrolled oscillations on 10 meters. This is intermittent but when it happens it pegs the meter when it's in the meter switch is in the Ic position. This seems to be the only band this radio does this in.

2012年8月28日 · I recently picked up a Kenwood TS-120S at a hamfest for what I thought was a fair price. I asked the seller if there was anything wrong with it and he showed my how sometimes the PLL would unlock and pushing on a particular connector would 'fix' it.

2021年1月6日 · While transmitting, I am slowly turning up the mic gain, trying to keep the ALC meter from deflecting to full readout. When the audio cuts out in the receiver, the transmitter power output is at full CW output, and the ALC meter shows full readout.

2011年4月25日 · It may work better to balance the SWR circuit, adjusting TC1 on the Filter board, at 15 meters. Too much protection action will prevent getting full output. Adjust VR1 on the Final board with care. S-Meter adjustments seem to be wrong in Service Manual.

2008年11月1日 · Check 20MHz signal at D24/D25 -- level should be greater than or equal to level of 10MHz seen for 20 meters. Check for and replace bad 2SC460 at Q24 and Q25. Several of these transistors have been seen to lose gain over time. Both Q24 and …

2016年1月24日 · I recently acquired a Trio TS-120s HF transceiver with an intermittent fault - when powered up the PLL would fail to lock , resulting in no TR or RX and no digital display - just two dots. Once the set warmed up the PLL would eventually lock , …

View and Download Kenwood TS-120S service manual online. HF SSB transceiver. TS-120S transceiver pdf manual download. Also for: Sp-120, Ps-30, At-120, Vfo-120.