The Stovebolt Site Forums The Shop Area Engine Shop Electronic Radio Noise

Stovebolters,

We had the restoration shop install an brand new 'Apache' radio from Retro Sound in our newly restored '58 Apache 3100 with a 235 straight 6, 12-volt electrical system. Radio works great using Blue Tooth, but when it comes to playing the AM/FM side of the radio, that is a different story.

Right away we started getting really high frequency squelching sounds randomly and on no particular radio station whenever trying to use the AM or FM radio. The restoration shop's and my agreed to solution was to purchase and install a suppressor. Bad news. That did not change anything.

Another school of thought is to change the plug wires to try and get some with better shielding. The wires I purchased for the re-build were suppose to be 'original' style wires and you cut them to the correct link and install the fittings to both ends. Restoration shop is of the opinion these wires do not provide adequate shielding from electronic noise. There is not near the electrical components on these old trucks as modern day vehicles, so what gives?

So, before purchasing new plug wires, I am turning to the masses. Has anyone else experienced this and if so what was your solution? If you purchased new plug and distributor/coil wires, what brand did you purchase? Would like to resolve this as the radio was not a cheap one and I would like to actually play the regular radio on occasion.

Look forwarded to reading your responses,

John
Restored '58 Apache 31
Raleigh, NC

Does the noise occur with the engine running?
How is the antenna and antenna cable installed?

They will probably move this thread to The Electrical Bay forum or the The Radio Bench forum.

The forum your in is for engine questions.

jorb,

You are right. This thread will likely get moved, but in the mean time.....

Just tried the radio without the engine running. Was not in the truck for an extended amount of time, but do get through all the FM and AM settings with no 'unwanted' noise.

I don't understand what I should be looking for to answer your question regarding the installation of the antenna and antenna cable.

John

You say the truck is 12V, what provides the charging, alternator or generator?
Try this test but only long enough to see if the noise is present or not. I'm talking seconds not minutes.....
Disconnect & remove the fan belt, start engine turn on radio and listen.

If no noise, the source is the charging system, troubleshoot accordingly.
If noise remains, it's not the charging system, continue troubleshooting the ign system.

Good luck

Volfandt,

Thank you. The 12V charging system is a generator.

I had the same problem. My guess is that it was due to my electronic ignition system after I removed the points. I also have a generator instead of an alternator. I purchased an antenna static filter that plugs into the antenna cord under the bench seat. It cured the problem for me. AM static is mostly due to a poor grounding source.

The antenna cable center conductor/wire could be grounded.
If antenna cable center conductor/wire is not shorting out to ground.
Do this:
Take radio main power wire and connect it to the trucks battery positive post.
Take radio ground wire and connect it to the trucks battery negative post.
Start truck Turn on radio.
Tell me what happens.

jorb,

Thanks. I will pass the on to the resto shop when I take the truck back in the week following Thanksgiving, so my reply to you will be a few weeks. Have a problem with the headlights going on and of(Not good) and the instrument cluster light only works with the high beam lights on. Electrical goblins at work. Will post the fix.

John

I don't have electronic ignition. I stayed with the old points and condenser system I had. Rebuilt the distributor.

What does removing the fan belt have to do with anything? Is it that it is not operating the generator?

Yes. No generator noise that way. Common diagnostic tool back in generator days.🛠

Justhorsenround

In another words Process of elimination

Exactly

Eliminating the charging system for the source of the noise.