transistor substitute

sccolbert · Post by **sccolbert** » Thu Jul 29, 2004 3:45 am

digikey has been on backorder for the transistor 2n3906 for position Q4, the part is listed at 200ma. I have the board assembled and the local radio shack has the same 2n3906 transistor but it is rated at 100ma. Will this be an acceptable substitute or do i need the 200ma part? Digi key has been on backorder for this for quite some time and does not when they will recieve a shipment.

Chris

repton · Post by **repton** » Fri Jul 30, 2004 7:47 am

Looking at the schematic Q4 is the feed for the tacho output, so for the purposes of getting the thing working I would assume it's very much optional. I would just leave it out for now.

Paul

Josh_b · Post by **Josh_b** » Fri Jul 30, 2004 9:33 am

will leavin the tranny out leave an openish circuit so it wont work?

repton · Post by **repton** » Fri Jul 30, 2004 2:57 pm

The tacho output won't work, but I think I'm right in saying everything else will. I guess it depends how important a working tach output is to the guy.

Josh_b · Post by **Josh_b** » Fri Jul 30, 2004 3:28 pm

when i left the output trannies off none of it worked

sccolbert · Post by **sccolbert** » Sat Jul 31, 2004 10:30 pm

doesnt really matter any more.....i just got the right transistor from digikey...it just came off backorder....thanks though

chris

Autosport Labs

transistor substitute

transistor substitute

transistor

i may be wrong

The tacho output won't work,

i seem to recall

doesnt really matter any more