2 pin microphone plug

[cobracon2]

Was surfing the bay and decided to get an old tube radio. I picked up a Hallicrafters Model CB-3A. I know it will be a lot of work to get going again but all the tubes are reasonable for the unit. Now looking at the pics it looks like it has a 2 pin microphone connection. My question is "Can you convert a 4 pin to a 2 pin?"

[Lost Ram]

Not sure what 4 pin you have. Example of an old standard d104, black and red are used for ptt, shield and white are audio if I am not mistaken, for isolation you can hook the ptt ground and audio shield together. This is just off the top of my head, you might want to look a wire diagram to be sure.

[MDYoungblood]

Old tubers are be fun to restore or they can make you lose your hair early in life whih was my case. Here is a good start,

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I wouldn't change out the plug, wire the new mic up for the radio, if you need help finding a plug I'm sure they are around. The radio is relay switching so the RX wire is not used, tell us what mic you want to wire and we can pin it out for you.

3's

Greg

[cobracon2]

The mic i think I will be using is an old Cobra 4 pin (easy to come by). I should be receiving the unit around friday, I can't wait. BTW, thanks for that link!!!

Also and good cleaning tips for the old tubers. I want this one to look nice inside and out.

[MDYoungblood]

An old Cobra mic will work, just don't hook up whatever color wire is on pin 4. Cleaning up the inside, I would blow the dust out of it and maybe use a small paint brush to loosen any debris, not a lot you can do if it's got any rot/rust. If you have to use water, use only distilled, there aren't any minerals that can cause a short, blow it off and let it dry thoroughly. I wouldn't use any kind of cleaner on the face plate, it would probably wash the print off.

3's

Greg

[PA629]

An old "Belly-Scratcher" CB-3A. When I was just a kid it was my first ever CB radio o/t than walkie-talkies, bought it used from a local business who was replacing their tube-type mobile rigs with "them thar new-fangled transistor things....". This was back around 1964 or so. Had a lot of fun with that old 8-channel rig. There was a retired guy who lived a mile or so away from me who was a Browning dealer, he showed me how to do some basic tuning on it, and I got my 2-pin mic plugs from him, seems the Brownings used the same plug, IIRC. Good luck restoring yours.

[jessejamesdallas]

Check around on the auction bay, there's probably a 2 pin to 4 pin adapter avalible so you don't need to rewire anything.

[cobracon2]

Believe it or not the radio is here already. The best part, it has two addons, one in each slot. The one right of the channel indicator is a dial that is numbered 1-8 and in the lest spot is a dial numbered 1-23. My question now is, how do I activate the vfo and what is the 1-8 dial used for?

The unit does power up, no magic smoke. There is a lot to be done, the power plug is a little loose and the knob need a good cleaning.

One last question. Does the mic need to be plugged in for receive to work? I put a dummy load on another cb and keyed channel 11 and the radio speaker did click. But no static just sitting there hooked to an antenna with squelsh turned off.

Thanks for all the help guys!!!!!!!

[MDYoungblood]

No it doesn't need a mic to receive.

3's

Greg

[cobracon2]

Well I was able to power the radio up and I'm getting receive. It comes and goes so I need to do some cleaning, but a great first step. The mic plug I ordered was female , so I need to change the plug in the radio. I can't find any 2 pin male mic plugs. Will post progress as I go.

[MDYoungblood]

I guess change it to a regular 4 pin and wire it so any Cobra, Uniden, Galaxy 4 pin mic would work. I did that to a lot of odd ball brand radios in the past so you could go and buy a mic right off the shelf and plug it in. You will probably need some DeoxIt for the pot's and recapping is the next step. The big filter caps are most likely dried up, that is why the receive is wondering.

3's

Greg

[cobracon2]

Will this work for cleaning the dials [Please login or register to view this link]

[MDYoungblood]

Hmm, use that very sparingly. Is this the mic plug you need to keep the radio original?
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3's

Greg

[cobracon2]

Nope, it needs to be male. Can't seem to find one anywhere.

[MDYoungblood]

Maybe a pic would give me an idea what it looks like, yes would be best to change it since they can't be found. I've been looking for a mic plug to fit a Icom Marine radio (M-700) for years, Icom doesn't even sell it in their parts list.

3's

Greg

[cobracon2]

Needs to look like this one;
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(edited by MDY, removed link and added pic)

[sonoma]

. I bought one a couple years ago

Cobracon I sent you a PM for a place that had them 2 years ago. I bought one then

[cobracon2]

. I bought one a couple years ago

Cobracon I sent you a PM for a place that had them 2 years ago. I bought one then

Thanks! I think I'll just change the radio connection. I ordered a male connector for the radio to soldier in. Now I need to start the cleaning and see whats going on with the caps.

[PA629]

I'm almost positive I have 1 or 2 of them around here. I looked where they SHOULD have been, but no dice. There's an outside chance they could be at my old house in town, I'll check this week if I get a chance.

[cobracon2]

I'm almost positive I have 1 or 2 of them around here. I looked where they SHOULD have been, but no dice. There's an outside chance they could be at my old house in town, I'll check this week if I get a chance.

Yeah these things are getting hard to find.

[443 Arizona]

ya know i dont think its possible to just put in a 4 pin jack.
there are 2 other switches that have to be thrown manually, and i think there are alot of interconnected wires doing other sorts of things.
the 2 pin mike is basically wired "live" and when you flip the other switches, you engage the mic.
might even be more than that,
it has been so many years i dont remember

[PA629]

I'm almost positive I have 1 or 2 of them around here. I looked where they SHOULD have been, but no dice. There's an outside chance they could be at my old house in town, I'll check this week if I get a chance.

Yeah these things are getting hard to find.

Like I said before, IIRC the old Browning Eagle bases used the same plugs, and there certainly are a lot of Browning collectors out there. Maybe one of the techs who work on the old tubers (like Barkett Elect.) would have one they'd part with.

[bluemeanie]

Theres a well known guy that has a lot of Browning and tram parts. He has the plugs same as older brownings hali and some audio equipment. Check the auction site too. Covering on a tree.

[cobracon2]

Thanks for the heads up. I have the parts now. But my fiancee is 39 weeks pregnant. So I haven't had much time to work on the radio yet. I did manage to give it a good cleaning and even had it receiving once. Looks like I need to change out those old bumble bee caps. Just need to sit down and figure out all the values that I am going to need. That's going to take a bit since I need to learn how to read the values.