MicroSquirt.com read only forum (Jan.15,2018)

Bruce Bowling wrote: You say you were running this with a 10K series resistor? This is kinda high, I am not sure if the opto will even read this reliably. - Bruce

Yes I put the 10k resistor inline per the advice of matt cramer as I was worried about frying the input like pommie had done in the past and it worked well untill I tried to run without it now it dont work at all.

Bruce Bowling wrote: You can check the opto circuit very easily - ground the opto- wire, take the opto+ wire and just tap it on the battery +12V repeatedly - this will simulate cranking RPM. You need to be in distributor mode when doing this (no wheel decode mode).- Bruce

Ive tried this in the past when I first couldnt get signal (that was all my fault) but it never worked Itried that the other night with no result. Iwill try all this again tonight and post the results. I really want this to work.
Thanks for the help and replies, Matt

A2TURBO wrote: Yes I put the 10k resistor inline per the advice of matt cramer as I was worried about frying the input like pommie had done in the past and it worked well untill I tried to run without it now it dont work at all.

Are you triggering off of the negative ignition coil side?

Check out the unit, if you still have problems email me offlist at bbowling@earthlink.net

I tested R20 and got a couple of values on the >+ setting the value was 1460 ohms, and the 20K setting was 2.32 so 2320? heres some pics any ideas? could I go to rad shack and get a new resistor of the value 680 ohm @1/4watt and replace?

It is a bit tricky, but I have soldered a through hole resistor in place of R20 before.

just for future reference heres the circut Ive been using to trigger uS. This worked until the resistor broke and I tried to run without it to get home. so it looks like the opto circut (R20) can be damaged with out a resistor.

Some coils can damage it; when hooked to a sensor instead, it's not at risk.

Bruce I tried the setup you suggested (Optoin+ to neg coil and Optoin- to +bat through a 4.7K resistor) and the unit suffered serious rests and was undrivable so far the best setup is my original Optoin+ to neg coil through a 10K resistor and Optoin- to chassis ground. it still has occasional resets but they usually donteven activate wue or ase. is there another setup you would like me to try? Im currently using my original setup and continuing with the tunning process (I got a good table it just a little to rich on top)