[Yaesu] FL7000 (boat-anchor)

[Kjell W. Strom]

Ross,

Rather early in the production life of FL-7000 an "RTTY" button
was added, which reduces the power supply voltage via a tap on
the transformer. This reduced the heat build-up during modes
like RTTY, but  at the expense of lower power out.

To just reduce the drive level does not help, since the heat
generated is still enough to trip the protection circuit.

The current guru on FL-7000 seems to be N4ATS. Contact him  at
grassa at earthlink.net

73,
Kjell, PB3SM - SM6CPI



-----Original Message-----
From: yaesu-bounces at contesting.com
[mailto:yaesu-bounces at contesting.com]On Behalf Of Ross
Sent: January 06, 2006 18:57
To: yaesu at contesting.com
Subject: Re: [Yaesu] FL7000 (boat-anchor)


Sean, and others,
Thanks for the comments, to give you some idea of the problem,
transmitting into a dummy load, with the FL7000 output at only
125watts,
it lasts 2minutes plus/minus 10secs before cutting out. I was
transmitting a cq in Olivia. Input to the FL7000 was 18-20watts.
To my mind a 400 watt amplifier should take at least 200watts of
digital mode output without a problem.
By the way Gary, it wouldn't be a good canoe anchor either.
Regards to all
Ross

 ----- Original Message -----
  From: Sean Sharkey
  To: Ross
  Cc: yaesu at contesting.com
  Sent: Friday, January 06, 2006 10:16 PM
  Subject: Re: [Yaesu] FL7000 (boat-anchor)


  Hi Ross,


  Have you tried running the amp into a 50 ohm dummy load,
  does the protection circuit still cut in?






  Sean.






  On 5 Jan 2006, at 21:32, Gary Smith wrote:





      I need some advice on what to do with an FL7000 amplifier,
(apart from

      using it as a boat-anchor).

      It has the problem of going into protective mode at very
power. I can get

      an output of no more than 100 watts on a digital mode

      before the protective circuitry cuts in and shuts it down.
Power off and

      on is the only way to reset it.

      Theoretically the mods to eliminate this problem have been
done, but it is

      still no better than when it was new.

      On SSB the problem is similar but it cuts out at a
slightly higher output.

      Can anyone advise me on what to do with this thing.





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