I have a Qkit Kit96 aka P16Pro40.  When I first put it together about 2
years ago I had a few quirks with the power system which I worked around.
It worked wonderfully and did every Pic on the list.

Fast forward after about a year of not using it I needed to program some 508's,
509, and 675's all of which I had done quite successfully previously. I 
managed
to actually program about 25% of what I needed to do so I started checking 
everything.
Everything would appear to program then fail with a verify error at 000h or 
some location
close to the beginning. This was done using IC-Prog v0.15d as PicallW was 
either not seeing
the hardware or stopping right at the beginning of the program cycle.

On the one end I have my old Acernote P166 Laptop running 98SE, cable is good.
I used Picallw and toggled all the bits and was getting good 5vdc changes. 
I had previously
used my 550mhz 98se desktop to program but I now have a 2.53ghz P4 machine 
running 2K Pro.
I didn't use it as the port only seemed to toggle from 0 to ~3.3vdc.

With the P16 connected to the cable and power applied via a 18.5vdc 1A wall 
wart I was getting
a fluctuation on the VPP voltage out of the 78L08. I should have seen 13 
but was getting
5ish until I tapped it with my meter at which point the power led would 
visibly brighten and
I would now see 13.04vdc. So I replaced the 78L08 with a spare I had. 
Result was no change.
Someone suggested checking the caps in the power section, so I replaced 
those, no change.

I noticed the VCC led was on slightly when it should have been dark. So I 
replaced its BC557
with one spare BC557 I had , no change.  I checked all the caps, and 
resistor values next
thinking one was off and causing the BC557 to "leak". They were all ok. So 
I pulled all the
BC557's out and replaced them with 2N3906 (with reversed pins) and that 
solved the led
being slightly lit. And most surprisingly it also solved the 13vdc 
fluctuation out on the 78L08
so I was now getting a very solid 13.04vdc right to the zip socket.

So I repeated the checkout and everything checked out perfectly. BUT it 
still won't program.

Does anyone have an idea what to try next?

Cheers

Dave

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