rick:
you were mentioning that you had some swr problems before hooking up the
amp.
Then you said you fixed those.
What I suspect is that you didn't actually completely fix those issues and
you still have a short or bad connection somewhere in the line between the
radio and antenna.
This problem may be dormant when you run only up to 100 watts, but as soon
as you put power to the antenna, the short becomes active again.
This would lead me to believe that there is either a shorted connecter, or a
single strand of brade touching a center conducter somewhere, that while on
relatively low power doesn't pose a problem with the tuner readjusting for
the discrepancy, but as soon as you punch up the power, things go way out of
whack due to the short.
on lower power, i think the tuner would account for getting your swr back to
normal, but add a bunch of rf in there, and the short becomes too much for
the tuner to counteract.
73
Colin, V A6BKX
----- Original Message -----
From: "Steve Forst" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, October 21, 2009 6:41 AM
Subject: Re: Amplifiers and SWR.
> Rick,
>
> I'll defer to those who have more experience running high power, and
> especially to those who have used this particular amp, but for what it's
> worth here's my two cents.
>
> While you are dealing with an older amp that could have who knows what
> going on with it due to age, previous misuse, or tweaking or
> modification
> over the years, perhaps you should be positive the rest of the station is
> up
> to snuff before sticking your grubby hands into the amp.
>
> Going from memory, I think your original problem was fluctuating swr
> especially when it was windy. This lead most of us who replied back
> then
> to think there was something going on outside, either antenna or feed
> line.
> Maybe you have separate issues going on here, or maybe just one thing
> that
> is giving you all this grief.
>
> Once again, if you had a dummy load and saw swr problems into the
> antenna,
> but not into the dummy load, this could help you isolate the problem
> area.
>
> Good luck, Steve KW3A
>
>
> ----- Original Message -----
> From: "Rick" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Wednesday, October 21, 2009 8:19 AM
> Subject: Re: Amplifiers and SWR.
>
>
>>I don't know how to adjust it.
>> I wouldn't want to try if it means opening up the case, not with all that
>> high voltage
>> I'd be afraid of accidently touching a electrolitic capasitor.
>> ----- Original Message -----
>> From: "Steve Dresser" <[log in to unmask]>
>> To: <[log in to unmask]>
>> Sent: Tuesday, October 20, 2009 5:09 PM
>> Subject: Re: Amplifiers and SWR.
>>
>>
>>> Rick,
>>>
>>> You may have some sort of matching network on the input side of your
>>> amplifier, and if it has changed, you should probably adjust it. I
>>> wouldn't
>>> try to correct this with the auto tuner in your radio.
>>>
>>> Steve
>>>
>>> ----- Original Message -----
>>> From: "Rick" <[log in to unmask]>
>>> To: <[log in to unmask]>
>>> Sent: Tuesday, October 20, 2009 12:24
>>> Subject: Amplifiers and SWR.
>>>
>>>
>>>> Hi list.
>>>> Using my TW-1 and MFJ versa tuner, I set my SWR as low as I can get it.
>>>> Say 1.01 to 1 on 20 meters. Then I tune the amp.
>>>> After tuning the amp I check my SWR again, and it's up to say 2.4 to 1.
>>>> Is this normal, and should I readjust the SWR again with the amp on?
>>>> Thanks in advance, and 7 3.
>>>>
>>
>
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