salvage a radio?

I found an old portable sterio but the cd player and tape deck did not work but the radio did so i took the pc board out that has the radio guts on but now im lost  the wires coming out of it say
Has anyone got a clue what thease mean  im guessing  rch and lch is right and left chanal for the speakers but the s/m and +b is throughing me

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NachoMahma7 years ago
.  s/m is probably a Stereo/Mono switch
.  rch and lch are right and left channel out. Use gnd to complete path.
.  gnd is ground or negative
.  B+ is the positive power in
That looks likely to me.

(The use of B to indicate power supply goes all the way back to when radios used tubes rather than transistors.)
nonamesleft (author)  orksecurity7 years ago
thanks for ya helps so if i stick +b and ground to a battery n an amp to the to the speaker output then i should get somewhere rite?
Most car stereos have an amp built in and are intended to drive speakers directly.
nonamesleft (author)  orksecurity7 years ago
this is not from a car sterio it is fron aportable cd tapedeck and radio kind of a boom box thing just cant work out where u give it power and what wire do you put on the speakers
Again, unless there was a second circuit card in the boombox it it presumably had enough of an amp to drive the box's speakers.

If so, the answers above are probably correct: rch goes to one terminal of right channel speaker, lch goes to the same terminal of the left channel speaker, the two remaining speaker terminals both go to ground. Battery - goes to ground, battery + goes to B+.

You haven't mentioned controls for volume and tuning. Presumably they're attached so you didn't need to ask us.

Note that the ideal thing would have been to take notes while you were disassembling this -- the existing connections would have told you how to put it back together.
nonamesleft (author)  orksecurity7 years ago
origonaly i took it apart as i was bord and it was going in the bid hand no intention to use any of it apart from the lcd screen for a computer but after bugin u guys wasnt worth it but had a thort about the radio i kept the board with the volume and tone on it and the little board with the radio guts on it

this is what i got to wortk with
thanks for all ya time n help
.  Slight correction: gnd is ground and also negative power in
lemonie7 years ago
s/m - some kind of control like a switch
rch - right (audio) channel
lch - left (audio) channel
gnd - common ground, 0V
+B - Power +V

frollard7 years ago
+B is probably battery, always connected, there's probably an ignition wire that tells the radio when the car is turned on. You're right about l and r.

I'm guessing s could be signal in or out. Some have wires that go out to an amplifier and they tell the amp to turn on when the stereo is on and only when the stereo is on.

nonamesleft (author)  frollard7 years ago
thanks for ya help is there a way i could plug this to a battery and get it working or is it just another thing for my endless box of random parts that are no use to anyone
oh and this was not taken from a car was a sony portable sterio

it was something like this but with a cd player
If you've got an appropriate battery (presumably 12V), and it was working when removed from the car... sure, why not?