default wrote:
On 4 Oct 2005 06:39:40 -0700, "Coyoteboy"
wrote:

It shouldn't be dismissed until you weigh the alternatives - perhaps a
unity gain op amp on each switch would make the resistance go away?
You know what impedance you need to match . . . I don't.

Im seeing your point, however im not sure what impedance i have to
match either. I know that im swapping over engine control from one ECU
to another, i know the resistance of some of the connections are to
sensors and are in the range of 0-3K, and some are connections to coils
of unknown resistance but that could be found out, and one is the knock
sensor, tuned to about 7KHz. The main problem is that the ECU is a
slighly unknown quantity as far as components, amps etc. I really
wanted a black-box-direct switching setup - any real resistance is
going to have possible implications i cant calculate for.

Appreciate your ideas though, i'll have some more thoughts around the
idea.

J