>Anyone want to buy my W-4 watt meter??
>
>It is an easy way to increase your output power for a modest price. I
>don't know why more of them are sought after.
>
>I used it this past weekend on the multiplier station using an amp which
>had never put out over about 1400 watts (as masured (..snicker..snicker) on
>my Bird) under any circumstance, but with that W-4 I was getting out 2 kw
>on the button.
>I know that this is only a DB or so increase, but it gave me a feeling of
>RF superiority and made my antennas work better (added bonus.)
>
>Clean piece of gear - $50
>
>73 de Steve, NJ4F
_________________________________________________________________________
Hmmmmmm, Steve, it is my considered opinion that you have been smitten
by the My-wattmeter-is-more-accurate-than-your-wattmeter syndrome. Please
note that syndrome means that there doesn't appear to be any basis in
fact for the symptoms (from a medical dictionary).
I have, over a career of nearly 40 years as an electronics engineer, had
occasion to use many Bird wattmeters. I have found that even when they
came straight out of PMEL, that they often will not give the same power
readings with another one set up side by side with it and alternately
using the same crystal unit.
In addition, I have almost never found one that gave the same reading
on two separate but identical crystal units. I believe that the problem
is most often the crystal units, themselves. I personally see no
justification for the apparent snobbery that Bird wattmeter owners
appear to have.
As for the accuracy of my Drake W4 wattmeter, I have taken the time and
effort to determine its accuracy with a 1500 watt mil-spec dummy load
and a tektronix scope (by measuring the voltage at the dummy load) and
I am satisfied that it is accurate within 5%. Perhaps that is a fluke.
Perhaps it is not. Other Drake W4 wattmeters might have some ideas on
that.
There may be several reasons why you found an apparent discrepancy. One
possibility suggests itself when you say you used it this past weekend
on a multiplier station using an amp which has never put out over about
1400 watts. That implies a station setup that was not in usual usage.
Did you check the SWR? A high SWR will manifest itself in an inaccurate
reading as to forward power. There are other possibilities that could
account for the apparent discrepancy.
I found it most interesting, though, that you have fallen prey to the old
"Mine-is-bigger-better-faster-more-accurate-etc-than-yours" knee-jerk
reaction that seems to plague the ham bands and associated reflectors
lately. It is also interesting that you have found it necessary to
announce it to the world.
Incidentally, I didn't realize it when I made my original post but I can
certainly understand why it appeared that I ran my linear at 1500 watts
only because I wanted it to last a long time.... not because I wanted to
remain on the legal side of the regulations - but that impression that
I unwittingly gave is inaccurate. I keep it at or below 1500 watts
when I am using it on the air. I have whistled into the mic when it was
connected to a 1500 watt dummy load and have seen the needle pegged at
2,000 watts. When in actual on-the-air usage, the wattmeter (average
power with speech processor on) almost never gets above 400 watts
indicated and NEVER above 600 watts average power. That assures that
I remain legal.
Incidentally, you shouldn't have any problem in selling your W4 wattmeter
for $50. It is a sought-after item.
Rod Fitz-Randolph, N5HV
w5hvv@aeneas.net
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