Found Old Cobra LTD 29 Classic, maintenance?

[therealdynamo]

Hey guys, so I was going through some of my grandfather's old things since he passed away last year and I found an old Cobra 29 LTD classic sitting in the back of the garage. Had a mic and a cigarette plug with so I plugged it in and it seemed to turn on and I could hear noise with the squelch down. Haven't tested it with an antenna yet (have one on order from Amazon).

Anyway, I was wondering if there is any maintenance or tests I should do with it? Or do I just put an antenna on it or see if it works? I know with cb stuff people take it in to shops to "peak and tune" and not sure what all I need to do.

 

[GrayJeep]

Controls and channel select switch might like a spray of tuner cleaner or Deoxit but that's it for 'maintenance.'

Connect it to an antenna and see if it works. If it works, you're good to go.

 

[jassing]

Avoid peak & tune. Usually, at best, shortens the life of the radio while providing only marginal benefits, at worse it does actual harm to the radio.
On old radios, I usually take a look at the electrolytic capacitors. Actually, on an old old radio, I just change them out; they do dry out.
Once you get the antenna, you want to listen for traffic somewhere, and try to transmit. The antenna needs to be on your car unless you bought a "no ground plane" antenna. If you don't hear anyone, you can try just transmitting occasionally "anyone there?" or "mic check". if it works,the other thing you want is an SWR meter so you can tune the antenna. You won't damage the radio with an untuned antenna, but you will really reduce your output on a mismatched antenna. If you're a member of a jeep club, you've got to know other people with CB's. Get them to loan you their SWR meter & explain how to use it. (You can also lean on them to check that you can actually receive & transmit rather than relying on luck.)

Enjoy!
-j

PS: If you find you enjoy using it, rather than peaking your radio, get a cheap amp like a KL203, they don't draw much power, and will help a lot; they are illegal, but so much of CB land is "wild wild west"; but the 203 won't get you into trouble by getting your neighbor's toaster to talk...

 

[bharvey2]

Controls and channel select switch might like a spray of tuner cleaner or Deoxit but that's it for 'maintenance.'

Connect it to an antenna and see if it works. If it works, you're good to go.

Tuner cleaner? Can you still buy that?

 

[WB9YBM]

Hey guys, so I was going through some of my grandfather's old things since he passed away last year and I found an old Cobra 29 LTD classic sitting in the back of the garage. Had a mic and a cigarette plug with so I plugged it in and it seemed to turn on and I could hear noise with the squelch down. Haven't tested it with an antenna yet (have one on order from Amazon).

Anyway, I was wondering if there is any maintenance or tests I should do with it? Or do I just put an antenna on it or see if it works? I know with cb stuff people take it in to shops to "peak and tune" and not sure what all I need to do.

If you need anything done to it, I'd recommend taking it to a CB shop--they've got the proper equipment, schematics, & etc.

 

[KK4JUG]

Tuner cleaner? Can you still buy that?

Sure. I use it on our band's mixers and that's a musical band, not a radio band and a sound mixer, not a Hamilton-Beach. A 16-channel mixer can easlly have over a hundred rotary and slide pots.

 

[bharvey2]

Sure. I use it on our band's mixers and that's a musical band, not a radio band and a sound mixer, not a Hamilton-Beach. A 16-channel mixer can easlly have over a hundred rotary and slide pots.

I figured the same product is still available but no one but the old school guys would know it as tuner cleaner. Also, I've had the wonderful opportunity to get to clean a mixer as you describe. I'd tell you I envy you but having done it, I'd be lying. Cleaning the Hamilton Beach is a lot easier.

 

[KK4JUG]

I figured the same product is still available but no one but the old school guys would know it as tuner cleaner. Also, I've had the wonderful opportunity to get to clean a mixer as you describe. I'd tell you I envy you but having done it, I'd be lying. Cleaning the Hamilton Beach is a lot easier.

I have to admit that cleaning the pots is as far as I'll go in maintaining the band's mixers. There's an awful lot of stuff hiding inside that I'm not qualified to mess with.

 

[GrayJeep]

Deoxit is the modern tuner cleaner. Works on potentiometers ("pots") and sliders. I fix up my flight simulator controls with it.

I'm still working off my first can of tuner cleaner from last century. Took my first ham radio tests on vacuum tube theory.

 

[bharvey2]

I have to admit that cleaning the pots is as far as I'll go in maintaining the band's mixers. There's an awful lot of stuff hiding inside that I'm not qualified to mess with.

Are we talking digital mixers? They make some activities a lot easier but when it comes to repair, you can get mixed up with some nasty voodoo real quick.

 

[KK4JUG]

Nope. Behringer analog.

 

[138BG]

On old radios, I usually take a look at the electrolytic capacitors. Actually, on an old old radio, I just change them out; they do dry out.

Old electrolytic capacitors don't just dry out, they leak electrolytic out around the leads. The fluid eats component leads and can do a real number on copper circuit traces if left too long. Similar to the corrosive glue that Uniden used back then. That's why a lot of folks re-cap and remove the glue from those classic radios when they find them. Lost a 23 channel SSB radio of my dads to leaking caps.

 

[WB9YBM]

Old electrolytic capacitors don't just dry out, they leak electrolytic out around the leads. The fluid eats component leads and can do a real number on copper circuit traces if left too long. Similar to the corrosive glue that Uniden used back then. That's why a lot of folks re-cap and remove the glue from those classic radios when they find them. Lost a 23 channel SSB radio of my dads to leaking caps.

I agree, although it seems like some people panic way before they really need to. For example I've got a transceiver built in the 1970s, has all original components (including electrolytic caps) and it's still works fine. The same thing with 2-3 power supplies I've got here. The one caveat though is that to last longer, I've been told the caps have to be used periodically (and unfortunately I don't have info on how often).

 

[138BG]

I agree, although it seems like some people panic way before they really need to.

I missed the panic part. Used regularly or not electrolytic caps have a definite lifespan. 40-50 years is probably beyond that lifespan. Even if they don't pop or leak they do drift out of tolerance as they age. For those clever/motivated enough to do their own replacement it's very reasonable from a cost perspective. Just good PM for a classic.

 

[slowmover]

I missed the panic part. Used regularly or not electrolytic caps have a definite lifespan. 40-50 years is probably beyond that lifespan. Even if they don't pop or leak they do drift out of tolerance as they age. For those clever/motivated enough to do their own replacement it's very reasonable from a cost perspective. Just good PM for a classic.

If it’s ten years old then sits on a shelf a few years, don’t expect much. 10-12 years is a good number for exceeding dead-solid reliable performance. Okay if at home. Not so on the road.

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