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V5 Rcv cuts out

andy@...
 

uBitx V 5.0 rcv cuts out. Click the PTT and it comes back. May stay or cut out again. 
Poor relay suspected. hfd27/012-s is used for all.
Using relay for small signal is not always ideal as contacts actually do better when actually passing some current. This is an issue when using for switching low level audio as well.
   I use 80 meters mostly so assuming its relTed to one relay.
Some hardware will "exercise" the relays by rapidly switching them on and off to "clean" them. 
I have recovered relays on the bench with a 555 and driving them on and off at a high rate for awhile to recover them.
Old ts430 and 440 relays suffered the same woes especially if radio sits for a year or so at a time and not used.
I suspect old stock and vertually no current to get contacts working.  This is not uncommon.
Is there better relays? Omron? 
VE6KP ANDY

andy@...
 

I should have said it cuts out but greatly reduced signal. Signals are not completely gone. If signals completely dissappeared i would suspect something else.

 

Hi,

If the relay passes only small signals and nothing else, then it must have some kind of contact maintenance current -- even high quality ones need this.

Here is a service bulletin for one of their transceivers needed adding on because they forgot to do this:  https://www.qsl.net/wb4kdi/Kenwood/TS-430S/Service%20Bulletins/asb0902.html  The bulletin has info on both cleaning the contacts and then setting up the circuit.

The Icom IC-730 also needed a circuit added on for the pre-amp relay which went out too because it switched only small signal and had no maintenace current.

I'm sure such a circuit could be added on to the ubitx if desired.

73,


Mark.