Technical Transistor Radio Doesn’t Always Turn On

I have a Ford OEM radio in my 62 Mercury. It turns on almost instantly so it’s got to be transistors. Except it doesn’t and I can’t think why this is the case.

If I turn the ignition on, then turn the radio on, then start the car it always works.

If the engine is running and I turn the radio on 9 times out of 10 it doesn’t come on.

Any ideas why?

 

Might be something to do with how much voltage is available when the engine is off or idling. Or it might be related to electrical noise.

There were some hybrid radios around in the early 60s that had both tubes and transistors.

 

Thanks @squirrel I’ll try it with the generator disconnected and see what happens

 

Some electronic components don't age too well, for example doing a health check on electrolytic capacitors may reveal something interesting.
Not quite sure how bad caps could cause the specific symptom you are seeing, but failing components can bring very interesting results that are hard to explain.

 

Have you ever checked to see if you have power to the radio when it won’t turn on?

 

I haven’t. It didn’t seem to me a likely scenario but I can check.

 

Apparently it’s tube and transistors

 

I like to verify the simple stuff first. Too many time I have torn into things that didn't work, and it was something else that was really simple and I overlooked it.

 

Hook up a small 12v light to the + supply into the radio, after the fuse . Leave it where you can see it. If it stays lit at all times, even if the radio doesn't work, you have internal problems. The old in-line fuse holders would often give trouble (corrosion/bad contact) and in tube radios the tubes would move in their sockets and lose contact with the base. Remove the tube, give the socket a squirt of switch cleaner (NOT WD40,etc) and re-insert. This would fix about 50% of the problems.

 

Had a play before work and it is definitely getting power all the time. I also noticed that when it doesn’t work you can hear it click through the speaker when you turn it off. Unfortunately after a couple of goes to see if rpm made a difference it worked and I can’t get it to not work again now.

 

Don't you hate it when problems seemingly fix themselves?

Sounds like another job for DeOxit D5.

 

DeOxit is a great product, highly recommended.

 

Think I’ve got to the bottom of it. Seems to be interference from power lines. Popped over to my folk’s and there’s a power line that crisscrosses their road and everytime you got near the radio went dead and then came back when you moved away.

 

Aliens!

 

Also ,If you go under an over pass or bridge the am radio will quit.
AM radio also quit with Wolfman Jack, Murry The Kay, Alan Freed and last Rush Limbaugh

 

That brings back memories of the cars I had with AM radios in the past. The one in the truck I am driving right now only picks up the AM station that I grew up listening to that is now run by the tribe here on the rez and you often get war dance music on it. Lots of Base on those though.

 

I’ve got Radio Gloucestershire on which is pretty yokel. Pigs, carrots, combines and the occasional thing going down in Cheltenham or Gloucester, the guy who wrote the tune to your national anthem was from there. There’s a flag and plaque in the cathedral.