> I just measured the OMNI VI + power meter calibration
>using an accurate power attenuator, dummy load, Bird
>thruline power/swr meter...
Yes, I just repeated your measurements here; essentially
the duplicate results. I, however, was using an RF Apps.
VFD meter along with the Bird with a 100 watt slug in place.
Omni meter set to read 15 watts, Bird meter reads 6 watts,
the VFD read 8 watts.
When the Omni meter read 25 watts, both the Bird and
VFD read 20 watts; with the Omni reading 50 watts,
the little line between 25 and 100 on the analog meter,
the Bird reads 39 and the VFD reads 38 watts. With
the Omni reading 100 watts, the Bird reads 70 watts,
the VFD, 69.
I suspect you will gain little from a readjustment of the
Omni pot you mentioned. Moving the pot probably
will not correct the nonlinearity being seen.
I certainly like their VFD for "on the air" peak power
read out using SSB near legal max peak, and is just
super for tuning up! It is instantaneous in response,
and clearly as accurate as the Bird for amateur use.
The Bird is too heavily damped for on-the-fly power
monitoring.
73, Jim, KH7M
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