[Fox_Tango] FL 101

[daveg]

Ken -

I've seen old tired 6JS6's behave somewhat like this.  What's the plate
current doing - is it normal at full power and dropping off when the output
power does?

Just guessing here - maybe a gassy tube...  with the top (main) cover off in
a fairly dark room key it up long enough to get the power fade.  You should
see just cathodes glowing orange, but little or no 'blue haze' in the tubes
and no plates glowing because they are overheated.  Same for the  driver.

Dave Goodfellow, N2EPV
have a 101EE and 101ZD

Kenneth Crips wrote:

> I have an FL101 transmitter which I have a problem I hope someone
> else out has had.  This unit has fresh 6JS6C's and a good driver.
> The problem is with the RF output. After tuning it up the output
> is about 120 watts dive give or take 5-10 watts depending on the band,
> and how hard I drive the finals, I normally hold it down to 100 watts.
> 35 watts CW and AM phone.  The problem is power fade.  When I first key
> the transmitter I have full output over a period of about five minutes
> the power drops back to about 12 watts which is the level the driver
> is exciting the finals.  When I unkey and wait for a few minutes it
> will return to a higher output about 80 or so watts.  This time when I
> key the transmitter the power drops off to about 12 watt over a period of
> several seconds.  Keep in mind The FL101 is a separate transmitter it's
> output section is identical to the FT-101 series. Any Ideas what might be
> wrong?
>
>                          Ken de W7ITC
>
> Kenneth Crips
> Amateur Radio Station W7ITC AMI-877
> Ten-Tec Argosy 525, TS-520SE, Heathkit SB200,
> R388/URR, R390A/URR, SBA-1, Gonset G64, HQ-129X,
> SP600-JX17, Hallicrafter SX101A, BC-312N.
>
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