Are you sure the power peak is on 75 meters and not on 40 meters with the PA
trying to double to 40 ? The plate tuning going to minimum capacitance is
suspicious.(And I assume you really mean plate tuning not the loading cap )
What is your load SWR while you are doing this ? Better yet use a dummy load
with known good swr - BUT still make sure the output is on the band you are
expecting ..
73 de hank K7HP
----- Original Message -----
From: "MIKE DURKIN" <patriot121@msn.com>
To: "amps fourm" <amps@contesting.com>
Sent: Wednesday, September 15, 2010 10:40 AM
Subject: Re: [Amps] Thp HL-2k
>
> Check that ..... its not burning off the contacts like last time !!!!!
>
> While set to operate on 75/80M - as the plate TUNE was being decreased (
> to almost minimum value) , power was still increasing -
> again around 900W the problem shows its self and im not sure why. It looks
> like it is arcking from the 75M extra tune cap ( C 44 ) contact to the 15M
> coil contact. They are just across the air gap from each other.
>
> Any one seen this before?? Maybe sticking some ceramic insulator
> between the two .. don't know.
>
> Mike
> KC7NOA
>
>
>
> From: patriot121@msn.com
> To: amps@contesting.com
> Subject: Thp HL-2k
> Date: Sun, 12 Sep 2010 08:37:12 -0700
>
>
>
>
>
>
>
>
> Has any one had issues with the HL-2K from THP - like acrking/vaporizing
> contacts on 75M....
>
> Iv blown off the contacts again - as the plate loading was being
> decreased, power was still increasing - again around 900W the problem
> shows its self and im not sure why. I haven't opened the amp yet to verify
> that the 75M & 40M contacts are cooked - im just guessing an ark from the
> 40m to the 75M ...... because the contacts were new and no groove was seen
> in the sliding plate. Q to high?? mabey decrease the tank coil by one turn
> ..??
>
> Mike
> KC7NOA
>
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> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
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