> Scott: I dont know how new yours is, but the newer OmniVI's had a mod so
> that if you kept the power supply on it would keep the reference oven on
> at all times even with the radio off, thereby reducing drift.
>
Keep in mind that the temperature regulated oven only stabilizes the
oscillator for the main clock. It is quite stable once the frequency is
properly adjusted against wwv but it's a touchy little trimmer and
difficult to set within a few cycles.
The annoying drift occurs in the bfo. This osc. is not temperature
regulated. Error from this oscillator is what causes your qsos to
complain about you being "off frequency".
The fact that the digital readout is off by 50 cycles doesn't matter
unless we are trying to link to an aplink or packet station. What is
frustrating is the warm-up drift and error in the bfo. Maybe this has
been improved in later production Omni's. My Omni 5's frequency readout
is probably not as accurate as the Omni 6 but the bfo drift is exactly
the same.
I've noticed that the bfo will drift during long cw qso's due to heat
buildup inside the radio. If the top cover is removed from the omni, the
drift is almost nil. I suggest better venilation. The speaker can be
removed from the Omn-6 and a small fan mounted in it's place. This
helped mine considerably.
N4LQ
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