Maratrac Intermittancy

[KA0XR]

I have a Motorola Maratrac in my car that seems to "hiccup" in audio when receiving very strong signals, such as strong 2 meter repeaters and local Weather Radio channels, sort of like a bad cell connection. This issue seems to occur when the radio is cold (my car sits outside in winter in Minnesota), but the receive operates normally after a good amount of time with the heat on, which is annoying.

Anyone have an idea why this might be happening or if there is a remedy other than warmer weather? I would think that a commercial radio would be able to handle cold temperatures. This hiccupping does not happen when listening to weaker signals.

 

[a417]

I have a Motorola Maratrac in my car that seems to "hiccup" in audio when receiving very strong signals, such as strong 2 meter repeaters and local Weather Radio channels, sort of like a bad cell connection. This issue seems to occur when the radio is cold (my car sits outside in winter in Minnesota), but the receive operates normally after a good amount of time with the heat on, which is annoying.

Anyone have an idea why this might be happening or if there is a remedy other than warmer weather? I would think that a commercial radio would be able to handle cold temperatures. This hiccupping does not happen when listening to weaker signals.

bad solder joint or other intemittent connection that is exacerbated when the cold weather makes materials contract. could be anywhere in the audio path up to the speaker driver coils. That radio is no spring chicken, it probably lived quite a life as a commercial radio before getting to your car...

 

[Otis413]

I have a very similar problem with my VHF Maratrac, it works good at a distance, but, as I get closer to home (my wife is a ham also and we talk on my commute home) The closer I get to home the worse the "stutter" gets, I had my XYL set her radios pwr to low but it didn't seem to make much difference. I thought it might be a squelch problem but if I hold down the [Mon] button and open the squelch I can hear her perfectly. ?? I have a spare so I just swapped it out for now, I'm also at a loss as to what would cause this. Now that the weather is warming up I might try it again and see if it makes a difference...
I'll keep an eye on this thread.

 

[a417]

much difference. I thought it might be a squelch problem but if I hold down the [Mon] button and open the squelch I can hear her perfectly.

It sure as hell sounds like a squelch problem, if it goes away with the deactivation of the squelch circuit (via the MON button)...

Have you been thru this page yet?

 

[Otis413]

It sure as hell sounds like a squelch problem, if it goes away with the deactivation of the squelch circuit (via the MON button)...

Have you been thru this page yet?

Beyond a quick check for bloated caps and loose connectors I haven't really dug into it yet, I'll check it out!

 

[Echo4Thirty]

Keep in mind that caps do not have to be bloated to be bad. Often the dielectric dries out or changes properties enough to push it out of spec. With that vintage radio, its time to completely recap it.

We have tons of Astro Spectras and their caps are acting wonky too and that line is a lot more recent.