[Elecraft] QRO precautions ??

[Charles Greene]

Hello,

I recently reactivated a Swan linear and an older Hallicrafter HT33A,  When 
I exceeded about 500 watts on 40 or 80, the GFI breaker in the upstairs 
bathroom would trip and the electric bed also upstairs would start 
running.  (A real No-No if the XYL was in it).  I had a lot of bothersome 
RF in the shack from a 135' OCF antenna that didn't cause any problems at 
100 watts.  I also had a little TVI in the TV upstairs.  Using an old 
linear, you miss QSK.  However I solved all of these problems.  On the GFI 
breaker, I replaced it; the new ones are RF resistant.  I used an AC line 
filter I had in the shack and that fixed the electric bed problem.  On the 
RF, I used all standard fixes: short grounds, better ground on the coax 
shield before coming into the shack.  All helped but  but it took a dozen 
or so turns of RG8X on a 2 gallon chlorix bottle where the coax came into 
the house to get rig of it completely.  I installed two LPF filters in the 
coax from each linear to its tuner and that took care of the TVI.  For QSK, 
I reactivated a QSK1500 external switching unit on the Swan and Omni-VI 
that gave me back QSK at anything less than 1500 watts.    On the newer 
linears, some of them have QSK built in, so if you want QSK, buy a linear 
with it build in.  I'm assuming the Elecraft linear has it.  It goes 
without saying that you need heavy duty coax switches, RG8 or at least RG8X 
coax and even LMR-400 on long runs.  You need high power antenna tuners, 
lightning arresters, heavy duty grounds and adequate power to the shack.  I 
have a separate 220 v circuit going to the shack.  Operating, you don't 
need a linear most of the time, especially on CW.  Sometimes it's helpful 
on SSB particularity on 20, 40 and 80.  Frankly, If I had to buy a new 3K 
linear (dollars), I'm not sure it would be worth it.  You have to see what 
kind of operating you do.  Of course, from Elecraft's point of view, if 
there are linears to be sold, a good, relatively inexpensive kit has a lot 
of potential.

At 01:31 PM 5/26/2005, you wrote:
>With the possible eminent presentation of a VERY QRO amplifier to  the
>Elecraft family, there is certain to be a number of us, with only  QRP 
>experience,
>jumping in and "playing" with gobs of RF energy for the very  first time. 
>Let's
>hear it from those with experience, some  do's, don'ts and caveats that go
>along with running the legal limit. I  hate learning stuff the hard way...
>
>Thanks,
>
>Bill  K3UJ
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73,  Chas,  W1CG