18 Jun
2007
18 Jun
'07
6:15 a.m.
Do you have a 'scope? If so, look at the
collecttors, coveniently on the
metal cans, of the 2N2222 or 2N2907 (they;re linked together). You should
see a 12V p-p square wave here (switching between ground and +12V
essentially. If not, suspect the transistors, If that signal is prensent,
check the charge pump compoentns.
Fixed!!!!
I replaced 2N2907, recalibrated 500 Khz frequency, and now there is -10V.
The drive now works like a charm.
Thank you very much to all, and expecially to Tony that was of very big
help.
Roberto