I didn't mean to imply that it should be tuned at a lower power level. I meant
that it should be tuned to its max rated output (most will make more than this
but may not be linear when they do) then switch to AM, send a carrier and
observe the output. If it's more than 25% of the max output, reduce drive
(only! Don't touch anything else!) to 25% of max output. Sorry if that wasn't
clear.
Kim N5OP
"People that make music together cannot be enemies, at least as long as the
music lasts." -- Paul Hindemith
> On Aug 1, 2014, at 20:06, "Bob McGraw - K4TAX" <RMcGraw@Blomand.net> wrote:
>
> Most 100 watt PEP transceivers will reduce power to 25 watts of carrier for
> the AM mode. Amps like the Centurion have about 10 dB to 11 dB of gain thus
> 25 watts of drive will produce about 250 watts of carrier.
>
> I never advocate tuning a linear amp at anything but for maximum output with
> recommended drive. Just keep the grid current and plate current at or below
> maximum rated values. Then if one wishes to reduce power or operate at a
> lesser level, reduce the drive and the amp will always be linear. Tuning at a
> lower power level will not assure linear operation and it can shorten tube
> life.
>
> 73
> Bob, K4TAX
>
>
> ----- Original Message ----- From: "Kim Elmore" <cw_de_n5op@sbcglobal.net>
> To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
> Sent: Friday, August 01, 2014 7:34 PM
> Subject: Re: [TenTec] Centurion and AM
>
>
>> How about this: Tune the amp for its maximum clean PEP output at whatever
>> drive level is needed. Switch to AM and adjust the carrier level to 1/4 of
>> that output. Then operate happily.
>>
>> Kim N5OP
>>
>>
>>> On 8/1/2014 7:28 PM, george fritkin via TenTec wrote:
>>> 200 to 250 watts AM results in 800 to 1000 watts PEP at 100% modulation.
>>> Three 811 tubes can not handle that power. However if you are using low
>>> level AM from your xcvr you probably won't get 100% modulation so it might
>>> not be a problem. If it were me, I would drop the power to 150 watts to be
>>> safe
>>> Just my opinion
>>> George, W6GF
>>>
>>>
>>> On Friday, August 1, 2014 4:57 PM, Robert <rmcgraw@blomand.net> wrote:
>>>
>>>
>>> Yes. Run about 200 to 250 watts of carrier BUT tune it for max output with
>>> 100 watts of drive. Then switch to AM mode and adjust drive as necessary.
>>> Do not change amp tuning after switching to AM mode.
>>>
>>>
>>>
>>> 73
>>> BOB, K4TAX
>>>
>>>
>>> Sent from my iPhone
>>>
>>>> On Aug 1, 2014, at 5:40 PM, Timothy Johnston
>>>> <timothy.f.johnston@gmail.com> wrote:
>>>>
>>>> Can the Centurion (422b) be used with AM mode? The manual does not mention
>>>> it.
>>>>
>>>> 73 de Tj, K4TFJ ...
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>>
>> --
>>
>> Kim Elmore, Ph.D. (Adj. Assoc. Prof., OU School of Meteorology, CCM, PP
>> SEL/MEL/Glider, N5OP, 2nd Class Radiotelegraph, GROL)
>>
>> /"In theory there is no difference between theory and practice. But, in
>> practice, there is." //-- Attributed to many people; it's so true that it
>> doesn't matter who said it./
>>
>> _______________________________________________
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>> TenTec@contesting.com
>> http://lists.contesting.com/mailman/listinfo/tentec
>
>
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