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HELP Using caps to briefly ground contact

W

Wendelloni

Jan 1, 1970
0
I am working on a Halloween project that uses a commercial sound
system. It's just a little box that plays sounds off Compact Flash
cards based on certain terminal outputs being grounded.

(link to EM3028B page:
http://www.eletech.com/Products/QuikWave_Boards/EM3028B/em3028b.htm)

Anyhow, for most of the connections I have done the sane thing of using
momentary push-buttons. But for authenticity reasons, there is one
terminal that needs to be connected to two toggle switches. In order
for other sounds not to get "locked out", I can't tie the switches
directly to ground. So, I used some caps to make the contacts briefly
go to (near) ground.

The problem comes from the fact that the switches are turned on in a
specific order (authenticity again). They activate other systems, but
share the same sound. The way it is now, if I flip switch 1 or 2
(numbered by the order they would be turned on), I get the sound. If,
I flip 2 then 1, I get the sound twice. But if I flip 1 then 2, I only
get the sound when I flip number 1.

The ONLY difference is that one switch is five feet from the terminal
(i.e. has five feet more wire). I tried to use a larger capacitor with
the switch 2, and when I got large enough it seemed to work but only
after a delay. I'm hoping there is something easy I can do to get the
switches to work in the right order. The actual switch mechanisms are
physically different and cannot be swapped.

Here's the basic circuit. The resistors are around 200 ohms and the
caps are 22uF.
http://i17.photobucket.com/albums/b63/wendelloni/Misc/circuit.jpg
 
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