odd readings from watt meters
On Feb 28, 9:11 pm, James Barrett wrote:
Hi, I have put up a dipole and I admit it is not a very good one, about
20 feet up, approx 60 ft. It works great as a receiving antenna and I'm
having fun listening, but so far no one can hear me. I have an Icom
IC-735, and using SSB, the watt meter on the radio shows full power as
I talk, but the watt meter on the tuner barely moves. In CW mode both
meters go all the way. Is this a typical symptom of a poor quality
antenna or does it indicate some other problem (besides my antenna
making skills)?
Any advice is appreciated.
Thanks,
Jim
Dunno. Seems a bit strange if no one can hear you.
It sounds like you are using an average reading meter,
vs a peak reading meter.
In the case of an average meter, on SSB voice peaks
you will usually see about 1/3 of your actual output.
IE: with a 100w radio, I'd expect peaks of appx 35w
on the meter. Barely moving seems to be a problem.
Being as the rig seems to be doing full power in CW
mode, I doubt the antenna is the problem. As long as
the SWR is under 2:1 you should be doing full output.
It can probably actually be a bit worse, and still do full
power in many cases.
So that makes me wonder if you might have a mic drive
problem, etc..
What mike are you using? Most older icoms require a
mic preamp. If not, you won't get full drive.
And I think the 735 is one that requires the mic preamp.
Even my 706 requires a preamp if I'm not using a stock
mic. If not, I won't get full drive.
Try the stock hand mike, if you are using something else,
and see what happens.
Average meters will usually read only about 1/3 of actual
output, but barely moving the meter is not right, if CW
if reading correctly. You should see peaks of 25-35
watts if it's working right. Near full power peaks if using
an actual peak reading meter. Most passive "capacitor"
meter hang circuits only read about 80% of full power.
MK
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