Sparkomatic CB5000 base won't transmit

[AC156]

I have a Sparkomatic CB5000 base that my dad bought new about 1976. It has sat on the shelf since the late 80s. The radio receives well, but won't transmit. When the mic is keyed, the needle moves a little, then goes down to zero. A click can be heard when it is keyed. Any idea what the problem is? I haven't found much info online about this radio. This radio looks a lot different than the Sparkomatic CB5001. It is pretty basic, with only squelch, volume, ANL, and channel selector.

[MDYoungblood]

Cool radio, pretty bare bones, it was made after the 40 channel switchover so that makes it around 1977. Info on the Spark-O-Matic radios is scarce. since it has receive that is a good thing, without seeing it first hand your description sounds like the relay needs cleaning and possibly the radio needs recapping. I would try some cleaner (I use DeoxIt) on the contact in the radio and the mic to see if it helps.

3's

Greg

[sonoma]

a long shot but since you said it starts to key then drops off could even be dirty mic contacts.

[AC156]

Thanks for the responses. I will try to take a look at it this weekend and let you know what I find out.

[Scipio Kid]

I wholeheartedly agree (with Greg). A carefully applied shot of Deoxit to critical switches and relays can do, and has done wonders to many an old antique radio, even those whose lifespan began at K-mart so many decades ago. (I've got an old Ford pickup with the original Sparkomatic speakers in the doors. Sadly, the matching 8-track stereo didn't make it, but the new Pioneer stereo sure sounds good through those old speakers).

I've always wondered who actually built CB radios and stereos and such for K-mart back then. I heard it was Cobra and Sears was Radio Shack. Penny's had a line too and I think Panasonic built all their electronic stuff. We had 4 or 5 really good CB radios from Sears back then and still have a couple kicking around. There never were a lot of those Sparkomatic CB's sold so you've got a real collectors item there I'd say. Does an electronic voice say "attention, K-mart shoppers" every time you turn it on?

Good luck on your Sparkomatic adventure.

[AC156]

Here is an update. I tried all I knew to do on the radio and finally took it to a local CB tech. He said the finals are blown. He checked a couple of different places and couldn't find any replacement finals. I guess the old radio will just sit on the shelf and look pretty for the time being.

[MDYoungblood]

Hmm, did he give you the transistor number, it is possible a old 23 channel radio could be a donor.

3's

Greg

[AC156]

He didn't say what is in it. I will take it apart tomorrow and see what it is.

[AC156]

It looks like the number on the transistors is C1173.

[MDYoungblood]

It looks like the number on the transistors is C1173.

You can search it, look for a 2SC1173 (NTE152), I guess the tech wasn't looking in the right places.

3's

Greg

[AC156]

I searched and found them in a few different places. My guess is he just didn't want to work on it. I think I will order a couple and replace them myself. I've never worked on radios, but I guess this one will be a good one to start with.

[MDYoungblood]

Yep, there is no harm in trying to fix a broken radio.

3's

Greg