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-----Original Message-----
From: gudguyham <gudguyham@aol.com>
To: paul <paul@paulbaldock.com>
Sent: Tue, May 2, 2017 07:16 AM
Subject: Re: [Amps] 144 MHz GS35B update
<div id="AOLMsgPart_2_13db94d9-4d7f-4e64-b18d-8a8815c81a76">
<div class="aolReplacedBody">Do you know how to test for a properly designed
input circuit for a GG amp? So many home brew builders are messing with tank
circuits to increase efficiency when often times the input circuit is
overlooked. To test to see how well your input circuit works you need to see
if the input swr remains 1 to 1 throughout the power input range and that the
swr is not affected by a change in the loading capacitor.
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-----Original Message-----
From: Paul Baldock <<a
href="mailto:paul@paulbaldock.com";>paul@paulbaldock.com</a>>
To: N1BUG <<a href="mailto:paul@n1bug.com";>paul@n1bug.com</a>>; 'Amps' <<a
href="mailto:Amps@contesting.com";>Amps@contesting.com</a>>
Sent: Mon, May 1, 2017 10:19 PM
Subject: Re: [Amps] 144 MHz GS35B update
Take one more turn off and you could probably get 600W out with 0W drive.
- Paul
At 01:50 PM 5/1/2017, N1BUG wrote:
>There we go. After reviewing pictures of several other amplifiers
>using this tube I removed one more turn from the coil on the tube
>side of the T match. Input SWR is 1:1 and the amp is making over 600
>watts out with 25 watts in. I plan to run it this way for a while
>before I go for the real QRO.
>
>Paul
>
>
>On 05/01/2017 02:40 PM, N1BUG wrote:
>>I'm seeing more RF output with the new configuration, about 500W for
>>somewhere around 25W drive. It appears I am going to have some fun
>>getting the input SWR down but I guess everyone does. That's
>>probably why there are so many slight variations on coil dimensions
>>among the various plans.
>>
>>My first try with both coils having 5 turns 15mm ID, 20mm long
>>resulted in minimum SWR of 3:1. My second try with 4 turns 15mm ID,
>>20mm long got it down to about 2.6:1. I am not sure whether to take
>>another turn off both coils or perhaps just the one on the tube
>>side. Many pictures of amps I have seen appeared to have less L on
>>the tube side although I don't see this mentioned in any
>>accompanying text.
>>
>>Paul
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