[Diy_efi] DIY WB 02 controller checkout problems

[Martin, Sam]

Guys,
   I have completed the controller. Got the connector from a junkyard (real
easy to find), and have everything installed in a radioshack project box
(actually looks really nice with the fuse, switch and LED mounted on the
front). Should be ready to go, but cannot get it to check out according to
www.diy-wb.com/diywbchk.htm 

If ya'll remember, I asked about the LM2902 earlier because the part number
was unavailable from Digikey. Initially I installed the Texas Instrument
chip (pn 296-6599-5-ND). Checkout procedure 42 would fail (voltage would not
rise) and 34 was kind of flakey (voltage would not drop). Switched to pn
LM2902NNS-ND. Everything seems to be OK with a few slightly off readings,
but 34 and 42 are odd (but better than with the TI chip). Below is a
breakdown of where I'm getting odd readings... (everything else checks out
OK)

test 12 (U3 pin 5 to J12) supposed to be 7.9-8.0V, I see 7.75V
test 13 (U3 pin 4 to J12) supposed to be 0V, I see 15.2mV
test 15 (U2 pin 14 to J7) supposed to be 2.75V, I see 2.648
test 21 (U2 pin 7 to J7)  supposed to be -3.4V, I see -3.329V
test 23 (Q4 pin 3 t0 J7)  supposed to be -3.5V, I see -3.43V
test 31 (U3 pin 1 to J7 switch closed)  supposed to be 4V, I see 3.864V
test 33 (U2 pin 8 to J7 switch open) supposed to be 2.7V, I see 2.617V
test 34 (U2 pin 8 to J7 switch closed) supposed to slowly go to -3.4V, I see
an instant -3.9V
test 42 (I used as 100 Ohm resistor)(J8 to to J12) supposed to start at 1.4V
and rise slowly (1.25 min) to 4.1V, I see a start at 1.3V and a quick rise
(~30 sec) to 4.3V.

I feel like I'm real close. Most of these probably don't matter. 34 & 42
have me the most concerned.

Help???

Sam Martin

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