[TenTec] Omni VI- PBT jumping after warm up.

[Dr. Gerald N. Johnson]

On Tue, 2007-03-13 at 17:17 -0500, k8vf_mark at centurytel.net wrote:
> "Its thermal. Could be an almost soldered connection, a connector, or
> inside a chip or transistor.
> 
> You need a freeze mist and some warm air (hot air gun or hair dryer).
> When it changes go cool a section. Then warm it, doing a binary chop
> (cutting the area heated and cooled each time) to isolate it. You may
> even get it down to the connection or device with the problem."
> 
> Yes, I figure to look in the area of the D5 varactor, thinking that the 
> voltage was being varied to it, causing it to shift.
> 
> Any other ideas are MUCH appreciated. I am not well experienced in 
> troubleshooting electronics but if you have a Steam operated pump or engine, 
> or a coal stoker I may be able to help.  ;-)   Mark
> 
First cool the whole radio. Then warm just half of it. Then cool just a
quarter. You may to try both halves and both quarters to see which has
the effect. Then split that part in half and keep heating and cooling
smaller fractions until there's only one part being heated and cooled
and causing the effect. A binary chop works every time and is often
faster than any other search technique.

73, Jerry, K0CQ