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Radio wiring

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Hey guys,

Tomorrow I am going to play around with my BMC radio. I have a few questions though.

- There is a positive/negative switch on the radio. This is a small round disc that I can pull out with 4 pins in it. I can put it back with the gap to "negative" (for my negative ground car). Is this indeed the way to do it or should it rotate? I seem to be only able to rotate the upper of the two discs and this does not seem to be of any electrical influence. The bottom disc does not seem to move.

- There are 4 wires. 1 green wire connected to the outer metal part. Is suppose this is ground? Then there is 1 black cable comming out of the internal part. And one cable consisting of two wires (stuck to eachother) comming out of the same internal hole.

Can anyone help me out here? /ubbthreads/images/graemlins/smile.gif Thnx!
 
Dreas, I can't help with the switch, but the wiring is within my capability.
The green wire is the ground, black is the power lead, and the two wires stuck together are for a single speaker.
Jeff
 
Interesting - Is is a stereo radio? The two wires stuck together - are they different colors? If it's not stereo, they may be the speaker wires. If it is, then they still may be speaker wires, one for each channel, and then the other terminal of the speaker would be grounded. The black wire, might be the power, though I've never seen black used for the "hot" wire. Otherwise, are you sure all the wires are there? Don't know about the disks - that's a new one on me. The green wire screwed to the frame of the radio should be ground.

Mickey
 
I am not sure all the wires are there but else I'd have nowhere to get the single black wire to /ubbthreads/images/graemlins/wink.gif I suppose it will be the "hot" wire. Could be because it's a pos/neg radio.

I can't believe it's a stereo radio so I'll suppose the two wire stuck to eachother (both the same color indeed) will be for the speakers. I did not expect two wires for 1 speaker but looking at the broken old speaker that got delivered with my car there seem to be indeed 2 connections.

Ahh one thing .. where is the antenna in this case? There is a screw with an arrow pointed to it that mentions the antenna. Should I put a wire there for testing (acting as an antenna)?
 
I'll shoot some photos of everything /ubbthreads/images/graemlins/smile.gif BRB /ubbthreads/images/graemlins/wink.gif
 
Just wondering about the pos/neg switch there seem to be too many useful holes if I'd be using it correctly now. The 4 pins however exist of two sets of two pins connected with eachother so it does connect differently when rotating it 1/4.
 
Never seen this type of hookup - However, from the looks of things, I would imagine that Jeff's and my ideas are correct. The two leads stuck together are for the speaker. As for the antenna, usually there is a jack for a plug - two conductor antenna cable. Move the green wire a bit and see if that's not the jack. The screw is for tuning the antenna for best reception.
 
Again, for the antenna jack, look on the side opposite the one with the power connection. Might be there.
 
The "standard" antenna plug is loosely referred to as a Motorola plug - here's a picture:
https://www.universal-radio.com/catalog/scanants/1790.html

Look for a hole in the radio that would accept this type plug. The center of the plug will be insulated from the surrounding metal jacket which contacts the walls of the socket sleeve in the radio.

All of this is assuming that your radio accepts this type of antenna connection. Maybe someone familiar with this radio will jump in here...Piman?
 
Dreas,

The answers to your orignal questions very simply are yes that is the way the switch works and Jeff has the correct answer on the cables.

That plug type "switch", just for everyones knowledge was a common practice back in the 60's and early 70's...Much more reliable and much cheaper than any switch could possibly be.
Unplug -- turn -- replug...Done. /ubbthreads/images/graemlins/cheers.gif

Mike
 
Awesome /ubbthreads/images/graemlins/smile.gif Now I think I've identifified all connecttions, let's finds a battery, speaker and test antenna to try it out /ubbthreads/images/graemlins/smile.gif Thanks a lot guys!
 
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