Dave- I just finished a set of measurements, and am putting them, and our
earlier posts, to the list- It may be of interest to others.
I hooked up to an MFJ "paint can" dummy load, and made measurements of
apparent power out, both with the tuner, and without. I used the power out
scale on the FT-920, for simplicity. (This is an LED scale, with a
discrimination of 5 watts) I thought this would be adequate, since you
reported a much larger shift in power. At each frequency, I measured the
power without the tuner, then keyed in the tuner to let it do its seeking,
then read the power out at key down- (I used CW mode) . I moved from 28.7
down to 28.2, at each .2 MHz, then (see below) did the same from 28.5 to
28.55, by .01 MHz.
I had intended to put in a table, but the readings do not warrant it.
Briefly, I read 80 watts at all frequencies, without the tuner, and either
90 or 85 watts with the tuner. The break between 90 and 85 watts came at
about 28.525 MHz. I repeated the test, going up in frequency, after the
initial set, which was going down in frequency. The results were the same.
In short- I do not see a drop in power across the 10M band, and I see a
higher power out (apparent) with the tuner, than without. There is an
apparent shift in power out at about 28.525 MHz, with the tuner, but no
shift without the tuner. I hope this helps you pin down the problem.
Bill- W4BSG
At 09:40 PM 11/30/1999 -0500, you wrote:
>Thanks Bill..It is very noticeible on mine. Dave
>----- Original Message -----
>
>> Dave- I have not noticed this, but I have not been paying detailed
>> attention to this aspect of its operation. Since you have brought it up- I
>> will check, and let you know what I find.
>> In all, I have been quite happy with the 920.
>>
>> Bill- W4BSG
>>
>> \At 05:15 PM 11/30/1999 -0500, you wrote:
>> >FT-920 users:
>> >Would like any input from other users of the 920 who are seeing output
>power
>> >fluxuation on 10 meters. While power out varies band to band, 10 seems
>the
>> >worse.
>> >Using a dummy load, have full out at 28.560 however, this drops off by
>15-20
>> >watts as one moves down to the bottom of the band. Inserting the auto
>tuner
>> >will also reduce power out further. The output varies, with the tuner in
>> >,from one band segmaent to another.
>> >I wonder if it is just my rig or if all 920's exhibit this problem ?.
>> >Thank you in advance for response. Dave K8GVK
-
Bill Aycock --- Persimmon Hill
Woodville, Alabama, US 35776
(in the N.E. corner of the State)
W4BSG -- Grid EM64vr
baycock@HiWAAY.net
w4bsg@arrl.net
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