VHF radio help needed

[One-eyed fat man]

Have an old SeaRanger 6000 VHF that is stuck on transmit. Removing the mike does not help so some kind of solid state keying circuit is "stuck" in the keyed position. Since the manufacturer is out of business, my question is, "Does any one have a schematic or service manual for this thing? Or know where I might be able to get one?"

 

[DP]

Re: VHF radio help needed

VHF radios have come down so much in cost and improved over the years that it much cheaper to replace than think about repairing.

 

[Ross J]

Re: VHF radio help needed

As an aircraft mechanic I would have thought you'd have someone at work that could service the radio. Forgive me if this sounds abrupt. Otherwise its not worth having if you can't get it serviced. Radios are bloody important!<br />Ross

 

[One-eyed fat man]

Re: VHF radio help needed

Certainly is cheaper to replace than to have repaired, IF I were hiring the job done. But, since it is a basement project, and would make a good spare if working, seemed like it was worth MY time to fix it. The reason I am trying to find a schematic is that it makes it simpler than trying to trace out the circuit chip by chip to find the culprit. While we have the facilities to do that, I don't want to spend that much time on it.

 

[Homerr]

Re: VHF radio help needed

Trace the TX circuit back. I bet it's one of those .02 diodes.<br /><br />I mess with CB's from time to time. On them, there is a 3 leg transistor (NPN or PNP could be either) that controls the TX/RX function. Sometimes if you get a steering diode (as I like to call them) shorted or open, it can cause that.<br /><br />Without the schematic, as you are aware, it's hard to tell.<br /><br />If the radio requires to be ground to TX, then obviously I would check grounding to the TX circuit. If it requires 2 of the mike wires to close, then the problem could be on either wire.<br /><br />The circuit is being closed somewhere. You could trace the circuit and maybe try the 'remove a component one-at-a-time trick' until it stops transmitting. Sometimes this is helpful in tracking down a bad component.<br /><br />Sounds like a good old fashioned circuit trace to me! (What a pain!)<br /><br />Good luck,<br /><br />H.