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Old 08-23-2008, 11:14 PM
bobterry99 bobterry99 is offline
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Join Date: May 2001
Location: Las Vegas, Atlanta
Posts: 670
I agree. A BJT would make the left digit brighter. A program change could also help by displaying the left digit 70% of the time and the right digit 30%, for example.

The difference in brightness is just noticable, and as I mentioned the photo exaggerates the difference somehow. But I suppose one may as well add another FET and resistor to the parts count and build the variation below.

A friend of mine works for Harris Semiconductor in Melbourne. He suggested adding small capacitors across the voltage regulator pins and a zener diode to protect the PIC from voltage spikes on the diagnostic socket. I don't think I'd bother with those. This is the same friend that originated the fix for flashing lights on early '90s instrument clusters (replacing the 470u capacitor on the circuit board).

I think I'm finished with and ready for my next project: one-touch operation of the power top for the R129 from the remote.
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Automated Code Reader for pre-'96 Diagnostics-pulse-code-reader-4-fets.jpg  
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