14-08-2023, 07:44 PM
Tx testing a Yaesu transceiver, I suddenly found ssb audio had stopped working, but cw was ok. The microphone was a new communications fist mic one by Shure, that I fitted the plug to a couple of years ago.
The mic socket was slightly loose, so, suspecting this I took cover off to check. All looked in order.
I tested the mic from plug end and the insert path was o/c! Fault found.
I took it apart so as to check the lead and the insert really was o/c.
I had a new boxed mic of same type and took it apart so as to pinch the insert. I tested first and it was around 2k.
I then fitted it into my faulty mic and tested for continuity of insert from the plug, all ok.
Plugging into the radio, still no ssb tx!
I made up a test lead and fed audio directly into the rig connector and ssb audio was ok.
I tested my repaired mic from plug end and it still showed oc.
So, I took it apart and this time this new insert also read o/c!
Removing the insert, the tag just fell away from the body. This is due to it being a very poor design as nothing there to prevent the tag moving and breaking the fine wire of the microphone insert thin wire.
So, I found an old mic and swapped the plug to it. Success, perfect operation.
Thing was, I had absolute trust in the Shure microphone being a quality brand. No more I am afraid!
Rob
The mic socket was slightly loose, so, suspecting this I took cover off to check. All looked in order.
I tested the mic from plug end and the insert path was o/c! Fault found.
I took it apart so as to check the lead and the insert really was o/c.
I had a new boxed mic of same type and took it apart so as to pinch the insert. I tested first and it was around 2k.
I then fitted it into my faulty mic and tested for continuity of insert from the plug, all ok.
Plugging into the radio, still no ssb tx!
I made up a test lead and fed audio directly into the rig connector and ssb audio was ok.
I tested my repaired mic from plug end and it still showed oc.
So, I took it apart and this time this new insert also read o/c!
Removing the insert, the tag just fell away from the body. This is due to it being a very poor design as nothing there to prevent the tag moving and breaking the fine wire of the microphone insert thin wire.
So, I found an old mic and swapped the plug to it. Success, perfect operation.
Thing was, I had absolute trust in the Shure microphone being a quality brand. No more I am afraid!
Rob
