Thanks to PY1NR.įor those who own TS-940S or TS-940SAT and want to fix it yourself, this is what I have done. Since then my TS-940SAT gained more Rx sensitivity. So, I needed to adjust VR-3 for meter pointer zero indication. When I tested, the S meter pointer deflected a little bit. Afterward, Q4 and Q5 faced to each other, and both Q10 faced to the same direction. Then I desoldered and reversed Q4 and one of Q10. The original position of 2SK125 for Q10 were facing to the same direction to form sort of double D. The original position of Q4 & Q5 were facing to each other to form sort of a letter O cut in the middle or a letter D and a reverse D. I found that the original position of a SK125 for Q4 (the second receive mixers) and a SK125 for Q10 (IF amplifier) were exactly the same as PY1NR had before. I began to open and check my TS-940SAT right away.

For TS-940S, PY1NR got an amazing result. Well, one element of amateur radio is a experimentation. He said that if you modify your own rig, its at your own risk. PY1NR recommended voltage measurements before and after correction. Bingo! I thought that this was the answer to my curiosity.

After he fixed it he claimed that his rig�s Rx gained 10 dB or more. Nelson Ricardo, PY1NR, has repositioned the SK125 semi-conductors/transistors of his TS-940S that caused the low sensitifity of its Rx. Last October�04 OM Thomas Sukamto, YC3BDJ, from East Java Province of Java Island, sent an email to an Internet maillist called Orari-News regarding an OM from Brazil who modified his TS-940S. Despite this fact, some DX operators around the world call this rig as a DX warrior. I thought I might have missed a factory recall on its Rx parts. I began to wonder last year why its Rx was weaker than the other Kenwood HF rigs or Icom. I have one of these rigs that has a built in auto tuner in it (TS-940S/AT). In 1985 Kenwood, a Japanese company, began to produce the TS-940S HF Transceiver and discontinued it in the 90s. KENWOOD TS940S AND TS940SAT MODIFICATION HOW TO INCREASE Rx SENSITIVITY OF KENWOOD TS-940S AND TS-940SATĪn article posted on the LongWire, December 2004, published by the Liverpool Amateur Repeater Club (LARC).

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