GE-PL5B2 "opto" from ALTEC units like 1591A

[jodun]

Hello.

Does anybody know the pinout and values of the bulb and resistor inside the GE-PL5B2, or GE-G202 Or how to test the unit? Or have any replacement ideas etc. It's a 4 pin. My tech has my 1591A in California but is taking avery long time to reply to me about the repair of the compressor circuit., so I thought I'd help look for info or find a replacement unit. All of the test voltages in the circuit are correct according to the schematic, so we're thinking it's the opto device

thanks so much

....later the next day.... the studio electronics tech in Cali has just replied that he has the new parts for my unit all ready to go..I'm no tech myself, but assume he is just backlogged.

 

[bru]

Did you ever figure out the resistor value of this opto?
Mine is dead but the bulb is good. Opened it up and the cadmium is all corroded and black.
Hoping whip up a new photocell or find a replacement.
I have SCOURED the internet for any info on this part and given up many times now.
Mine had the same markings and was silver with an orange dot. I have seen others with a black can, but am unsure of their labels.

 

[jensenmann]

I´ve been down that road some years ago. Back then the original part was unobtainium. If David Kulka has some of these in stock then buy it from him. I don´t know of any other source for this particular opto.

 

[mitsos]

I might have access to one later this coming week, but maybe not.  What I would do is stick a trimpot in there, say 250K, wired as a variable resistor. Start out with it at max resistance.  Inject a signal to the comp and start turning the pot until you get some GR. Turn it back until it goes to unity, remove and measure resistance.  I think that should be close to the max resistance of the LDR, but then we still won't know anything about it's sensitivity to light, or how fast it's resistance goes to zero, compared to the original. But it may get you a semi-working compressor.

 

[bru]

Thanks for that Mitsos. It's not really a precision comp anyway, so it'll at least have reasonable functionality at that point.
David Kulka's company said they've got none and no source at this point.
Anyone else able to chime in? I've heard of some tech's homebrewing something as a replacement.

 

[GRS]

Hello.

Does anybody know the pinout and values of the bulb and resistor inside the GE-PL5B2, or GE-G202 Or how to test the unit? Or have any replacement ideas etc. It's a 4 pin. My tech has my 1591A in California but is taking avery long time to reply to me about the repair of the compressor circuit., so I thought I'd help look for info or find a replacement unit. All of the test voltages in the circuit are correct according to the schematic, so we're thinking it's the opto device

thanks so much

....later the next day.... the studio electronics tech in Cali has just replied that he has the new parts for my unit all ready to go..I'm no tech myself, but assume he is just backlogged.

I know this is many years old but while trying to find the specs for the GE PL-5B2 I found in my junk drawer (in its original package!), I found your post. If it's still an issue for you, I'd be happy to mail you the one I have, new and unused! Email me at [email protected].