[TenTec] Ten-Tec service

[Carl Morris, WN3DUG]

Bob & Don,

The 1 uF Capacitor was added to prevent "Resets" on
the 1220's microprocessor, due to noise spikes.

I had problems on my 1220 until Ten-Tec Service told
me to add this cap, and then the problems went away.

I actually used a 4.7 uF cap, at the time, and my notes
say "to prevent 'Glitches' on the Master Clear Micro-
Processor signal from causing frequency changes,etc."

Another cap not normally included or installed in the
1220 when built, is C86 (4,700 uF - 35VDC Electrolytic),
which helps resolve ignition noise problems, and is
discussed on Page 15 (Service section) of my 1220
manual.  Ten-Tec gives some P/N examples for this
part in the 1220 manual and also a Ten-Tec Part No.
23320 for obtaining from Ten-Tec.

There is space on the PCB (C86) to install this capacitor,
but there is a limit on the physical size allowed for the cap.
Again, I installed this cap and never had any more noise
problems while mobile.

72/73, Carl, WN3DUG
cwmorris at pa.net