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Eike Lantzsch, ZP6CGE
 
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Hi Chuck:
thank you for taking the time.

Chuck wrote:
Hello Eike,

Just curious. You used the DAIWA to measure the 25W into the dummy load
also?

No, it was measured with the power meter of a Motorola test set.

Something is not right. The measured 14 watts could indicate a mismatch,
but that would surely show up as an SWR greater than 1:1.

Have you tested the DAIWA SWR function independently? Perhaps you have
two problems, rather than one? Is the DAIWA SWR meter calibrated for VHF?


Makes me curious too because Shakespeare states an SWR of 1.5:1 and
the meter showed zilch reflected power. But the test with open and
shorted coax gave reasonable reflected power reading. But maybe the
DAIWA has a problem too. It alledgedly works for 140 to 525MHz.
Last time I used it, it gave me precise enough readings to
build a vertical lambda-half antenna with cavity resonator on
478.45MHz[*]. This antenna performs well up to over 50km with 20Watts
on a 30m tower and a walkie-talkie on the other side behind the
horizon. The HB9CV, which I built, reaches repeaters more than 120km
away with just 0.6W on 145MHz[**]. This is from the same location on
the same tower as the UHF antenna. So my knowledge of the accuracy
of the DAIWA SWR meter is only anecdotal.
If I only had a BIRD meter ...

Besides: The Shakespeare 8' antennas are rated as 6dB antennas.
6dB over what? Over a dipole or over a monopole?
That should either read dBd or dBi.

Good luck!

Chuck

Thank you.
Kind regards, Eike
[*] comercial license
[**] amateur radio license