Hi all,
> The real problem with the peak reading meter is that most
>of them don't. If it cost less then 300 bux, it doesn't read
>peak no matter what the ads say.
>
> For instance, the MFJ, the Vectronics, and the Paslstar,
>all use a series resistor and a small shunt cap for their
>so-called peak detector.
So, where does the RF Applications Inc., P-3000
fit into this discussion? Have just had mine upgraded
at the factory to V2.0 firmware. Unit uses 1N5711
diode detectors. Before V2.0, manual accuracy
was said to be +/- 10%, plus, minus the analog to
digital converter resolution. Not sure what the
accuracy is supposed to be now, but some
implications that it might approach +/-5% similar
to the Bird 43, not sure. Problem I have with the
Bird is the amazingly slow response time, tough
to tune up to max with such sluggish response;
and the peak mod to the Bird does not seem to
be any faster in responding -- I mean it seems to
take seconds for the meter needle to reach max.
One Bird 43 in use here is s/n 15794, wonder when
it was built? My newest 43 is s/n 277093--huge
delta between the two, hi!
So use the bargraph on the P-3000 (which is ~0.1
second response) to tune/load adjustments. Also tune
up with about 60 wpm dits from the CW keyer, per
idea by Rich; bargraph peak power indicator works
great this way. Guess the little 0.0047uf capacitor
following the 1N5711 in the P-3000 directional coupler
unit can reach peak "power", and hold, or at least store
up to be sampled; seems to "work" ok, hi.
73, Jim, KH7M
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