Hello,
 
Only took a few temp photos...
_http://michail.selfip.com/temp/_ (http://michail.selfip.com/temp/) 
 
Real fast - without powering up and taking apart wire loom
 
3 octal sockets.
Pin 1 on each tied together and go to input or output side of 7805   (can't 
tell since using same color)
Pin 8 on each tied together and go to ground
Pin 7 on each tied together and go to a transistor
other pins go to various spots connected to chips.
 
Chips....
 
2x 7448
1x 74185
1x 7410
1x 7400
2x 7483
 
So, appears the guess about a rotary dial for score is looking close.
 
Michail
 
 
 
 
In a message dated 5/24/2011 9:56:54 A.M. Pacific Daylight Time,  
dfor...@dakotacom.net writes:

On  5/23/11 8:27 PM, micha...@aol.com wrote:
> I purchased this item on  ebay.
>  http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItemVersion&item=280660703999
>  <http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItemVersion&item=280660703999>
>  Anyone have an idea of what the circuit is, or should I setup better
>  pictures.
> Michail

This is clearly a one-off device, not  production. Perhaps they made a 
few of them.

The octal sockets  could be connectors to cable-mounted switches used to 
control the display.  For example, a scoreboard for a gymnasium would use 
remote switches to  control the score.

You would have to trace out the schematic diagram to  know for sure what 
it does, and even then, there will be some  guessing.

It would be very helpful to know what ICs are installed on  the board. I 
assume that the two ICs feeding the transistors are 7448 or  similar BCD 
to 7 segment decoders. There are 5 more ICs, which could be  latches, 
counters or some combination of these.

Can you take a  clear photo of the top of the board, showing all the ICs? 
Or at least make  a list of the IC numbers? They'll all start with 74.


-- 
David  Forbes, Tucson AZ

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