*O.K. folks this was a strange one. Feedback needed.*
*
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*
*The problem was that after being on about 3 minutes, the display and
frequency would drop by about 200-500 Hz when the radio was keyed. When
first turned on everything was Fine Business. With some troubleshooting I
found that the regulated voltage was dropping by between 0.4 to 0.7 volt
when the transmitter was keyed, depending on how long the radio had been
on. This is the voltage from pin 2 of IC-1 and the Emitter of the pass
regulator Q-11 on the Control Board. It feeds the VFO/PTO circuits and a
varactor diode in the Offset Tuning which are voltage critical. Looking at
the schematic again. It was noticed that the Lamp for the Meter was fed
through this regulated source. Removing the meter Lamp and after about a 2
minute cool down, the radio worked just fine. Looking at the Lamp, there
were no markings to be found. Probably Radio Shack. By using the spare lamp
from my Paragon the problem did not occur. After 6 hours of operation and a
good tune up/alignment. Nobody could not ask for a better working radio.
So, in the same fashion as the Paragon was done, I busted the glass out of
the No Name Lamp and placed one of my handy dandy ( low current ) LED's in
circuit. Everything is now working Great. The meter is a very pretty Bluish
White.................** I need an Elmer or Ten Tec guru to answer some
questions. Were there ever any issues with the Control Board in the Omni
series? Was the Lamp/Bulb just pulling more current than the little
regulator circuit could be happy with? Anyone with knowledge or feedback
about this strange finding would be most helpful. This from the Proud New
Owner of a very Minty Omni D/b .....*
*
73 to all de Wade/KJ4WS*
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