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In Search Of A Manual

R

RadioTom-1

Guest
Hello out there!

I am in need of a manual for the Control Design Corporation 25Hz tone decoder, model CD25S. They have a 12-position barrier strip for I/O, but nothing's labeled. ??? A note on one of the units I have hints it's got optoisolator outputs rather than relays, which an examination of the boards seems to bear out. It's on 2 PC boards not counting the power supply, in a 1RU chassis.

Any help at all would be appreciated... even just the connections would give me a starting place.

Thanks!
 
Should be pretty easy to trace. First find the connections for the cable shields. They should all be tied together within the unit. Easy to find with a multimeter.
Next, feed audio into the unit. I'd start with the first two terminals. They will probably be the left channel input. Find the output for that channel with an amplifier and speaker.
Do the same thing for the other channel. The remaining connections will be the EOM closure.
You can identify the left channel by feeding a 25Hz tone into the input. Whichever channel causes an EOM closure is the left channel.
I'll bet that you can find the correct connections in only a few minutes.
 
;D

only a few things wrong -

1) none of the wires inside the chassis are shielded.... that was my first thought, as well...

2) it's a dual-unit, so there's TWO sets to try and figure out, although it's not an insurmountable obstacle.... Some syndicators used a right-channel tone to fire rewind on a current-hits reel, for example. I have some possible leads for guys that actually worked for the company or one of its predecessors or successors; one, in fact, still works in broadcast automation for RCS...

meanwhile; still looking...
 
Considering the age of the unit (and I remember Control Design back at least to the late 70's) you would probably want to pull the unit apart and replace the electrolytics - why not just pull the board out and draw up a simple schematic. That unit can't be all the elaborate considering the vintage.
 
It's beginning to look like that's what I'm going to have to do. <sigh>

Oh, well... it'll keep me off the streets this summer..... ;D :D ;)
 
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