Guys,
I just spent 2 days trying to trouble shoot a weird
problem that I can not figure out. It started when I
modified an Xtall for computer control via the printer
port. All I did was make up the cable using the
BS170's and pulled the PIC and plugged the wires into
the socket in pins 8 for ground and pins 2 and 3. The
Xtall worked perfect with PowerSDR and si570.exe. The
only problem was the SI570 in the Xtall was the LDVS
version and I knew it would not drive the Softrock
directly so I ordered a CMOS version. I removed the
LDVS (was not fun) and CAREFULLY soldered in the CMOS
version. The CMOS version worked with the PIC so I
removed the PIC and plugged in the printer port
interface wires and it did not work at all. I tried
changing the pull ups to 10 k and adding the OE
(output enable) wired to 3 v still nothing. Then in
total desperation I removed the CMOS (not fun again)
and soldered in the LDVS version and everything is
working once again...am I missing something?
thanks for your help
Mike WA3O
