[Kenwood] TM742a Problem

[Eric Dobrowansky]

I am having a problem with my TM742A mobile.  The unit will not turn on. All
the basic stuff checks ok - +12v into the three band units, and the B+ pins
from the band units to the control unit check good. IIRC, the Q101 PNP
transistor which switches B+ to the 8v reg, audio ics, and other components
down line is not turning on. It checks good, as well as the components
before it, which is a small NPN transistor that turns on Q101 via the main
processor. The 32.768 crystal and 4.17? crystals for the CPUs seem to be
oscillating, according to a scope check. I am guessing that there is
something else keeping the CPU from triggering the Q101 stage. The
electrolytic caps in the circuits look ok also. The radio worked fine before
sitting in storage for a year or so.

Any ideas?


Eric
KE2D