Re: TZ Prox Switch #26

On May 25, 7:49 am, kenny_ii <kenny_...@xxxxxxxxx> wrote:
I have re-engineered this board set and have been selling it through
Pinpoint Electronics for a few months now. I have made several posts
here about the theory of operation over the past couple of years along
with detailed instructions on how to repair a Switch 26 board. A
properly working system does not require twisted wires to work right.
It is a work around for a poorly tuned sensor. Not a bad work around
mind you, but a work around none the less.

Adding a resistor will only help by accident. Part of the correct fix
is a higher value resistor for R1. Use a 20 k pot and start with a
value of around 15k. The tank circuit of C1, C2 and L1 needs to be re-
tuned as well. In order to get an adjustable, reliable sensor, all
these components should be re-valued and then adjusted for each
individual game. Not hard to do, but it takes a few hours. Or, you
can buy a board with it all done for you if you want, email me for
details for fixing your game or buying a board, either way.

K2



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Does this mean the replacement board is defective? If all other
switches work in this column and row, and I can activate the input by
touch the wires, then this pretty much rules out wiring. Does anyone
have the fix for this that is guaranteed to work (new boards etc.)

Thank you,- Hide quoted text -

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Here's some quick stuff on the problem.

http://www.iobium.com/twilight_zone_switch_26_eddy.htm-Hide quoted text -

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I agree- why they felt that they had to run at 3MHz is beyond me. But
that is what we have to work with in the case of these new replacement
boards. The resistor fix doesn't work by accident - it brings the
damping threshhold into the range of the coil and connection. A pot is
nice because it means that you don't have to adjust the sensor about.

.

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