Film-Tech Forum ARCHIVE: Stereo Solar Cell Connection on CP500 Query

This is topic Stereo Solar Cell Connection on CP500 Query in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Demetris Thoupis (Member # 833) on 01-09-2004, 03:28 AM:

Hello all,
Just out of curiosity, has anyone tried connecting the L- and R- wires from a stereo solar cell (not a Reverse Scan LED) directly to the chassi of the plug which connects on the CP500? instead on the corresponding pins? What would be the outcome? Would the sound still be ok? Because basically the L- and R- connection derives from the Ground of the Solar Cell? So. What will happen if anyone solders directly to the chassi of the plug instead of the pins the L- and R-?

Demetris Thoupis
Being a Projectionist is not a job, Its an ART

Posted by Steve Guttag (Member # 268) on 01-09-2004, 08:09 AM:

You are incorrect...the L- and R- are not "ground" but on old solar cells common to each other. On the large DP70 solar cells they actually had four separate wires since they were distinctly separate cells.

What you would, in effect, do if you tied the "-" terminals to ground is to unbalance the cell line and open yourself up to noise and you would take a 6dB hit on the input...all this presumes that the input is ground referenced too...some are transformer and you would get nothing.

Some processors, notably Kintek on their KT-700 did use an unbalanced scheme on their input and it did suffer for it...with a notable snap on any xenon strike.

So, if you have a decent processor with a balanced input then for what possible reason would you want to wire an input unbalanced rather than balanced? It just sounds silly.

Steve

Posted by Demetris Thoupis (Member # 833) on 01-09-2004, 08:43 AM:

Sorry for stating "ground". My mistake. SHOOT ME!!! AAAA [Smile]

Anyway. I meant Common. But I had mentioned above that is simply out of curiosity that I am asking this question. Still if this type of connection is used, will this mean that the signal input to the processor will be lower therefore you won't be able to obtain good solar cell alingment?
Demetris Thoupis.

Being a Projectionist is not a JOB. It is an ART