TS-940S receiver is numb - Hears nothing lower than 1mv
I just upgraded a customers TS-940 with a new power supply kit and on testing the receive sensitivity, found that the receiver only responds to signals greater than about 1mv. The attenuator works fine, and the transmitter works well. Just a really numb receiver.
Where is the best place to start? I do know the answer but want to get others involved in getting this awesome radio back on the air! Jeff AK6OK
Well, this one was pretty easy! On the back of the TS-940S, there is a switch marked Rx Ant Switch. You want this switch in the OFF position if you are using a single antenna. If you are using 2 antennas, you want it in the On position. Using 1 antenna with the switch ON will cause the receiver to hear very little! The customer had switched it to the ON position and I was unaware...
This is like the drake receive switch that gets moved when you pick it up. This has got me a few times.
Just thought of this, the 930 has a pretty weak amplifier switching relay. Is there a work around?
There are a few transceivers with this type of a switch on the back. And yes, the antenna switching relay could always be suspect when the sensitivity remains poor. Good thought and thanks for bringing it up! Jeff AK6OK