[Kenwood] TS950SDX - High noise with no antenna

[Steve London]

My TS950SDX has recently developed a problem. Even with no antenna connected, 
there is a high level of white noise - about S5. It seems related to the 
74LS145's used to select the RF bandpass filters. Replacing the 74LS145's has no 
effect. However, manually grounding the appropriate pin of the 74LS145 (rather 
than relying on the 74LS145 to electrically ground the pin) does eliminate the 
white noise (and restores normal operation on the chosen band).

Anyone ever see this problem, and have a fix ?

Thanks and 73,
Steve, N2IC