>
>The 87a should shut off if you over-dive it. Let the amplifier safety
>circuits take care of the problem.
>
>Although and ALC circuit just in case is a good idea. I would not rely on it
>for everyday use. It most likely result in splattering.
>
/\ amen, Jim
>
>
>
>----- Original Message -----
>From: "Curt Terwilliger" <ki6j@hotmail.com>
>To: <amps@contesting.com>
>Sent: Thursday, July 26, 2001 6:00 PM
>Subject: [AMPS] FT100D driving Alpha 87a
>
>
>>
>> I am using an FT1000D to drive an Alpha 87a, and am thinking of building a
>> "DC ALC" circuit to throttle back the juice to 60-80W out whenever the amp
>> is in "Operate" mode (because otherwise one day in the heat of battle I
>will
>> forget to reduce the drive power manually and probably cook the 3CX800s).
>>
>> This would not be RF derived ALC, just a DC voltage applied in steady
>state
>> to reduce the power in the same manner as turning down the drive control
>on
>> the front panel.
>>
>> AG6K, to whom I earlier mentioned this plan, has observed that using
>> suitable cathode resistors might be a more simple and reliable way to
>allow
>> the Alpha to accept a full 200W of drive. Point taken, although I am not
>> keen on adding 100W of dissipation to the cathode compartment and am
>willing
>> to take my chances with the reliability of an active circuit.
>>
>> I was wondering what others think about this DC ALC approach, and if
>anyone
>> is currently using it?
>>
>> Tnx es 73,
>>
>> Curt W6XJ
>>
>>
>>
>>
>> _________________________________________________________________
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>>
>>
>> --
>> FAQ on WWW: http://www.contesting.com/FAQ/amps
>> Submissions: amps@contesting.com
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>> Problems: owner-amps@contesting.com
>>
>
>
>--
>FAQ on WWW: http://www.contesting.com/FAQ/amps
>Submissions: amps@contesting.com
>Administrative requests: amps-REQUEST@contesting.com
>Problems: owner-amps@contesting.com
>
>
- R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures.
end
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