<G3SEK@ifwtech.demon.co.uk>,
"AMPS" <amps@contesting.com>
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>
>This problem may fade away when traditional output meters, hopefully, will
>be replaced more and more with pep meters. The problem will remain as long
>as some operators want big excursions on their meters and do not know the
>difference between pep and average readings. In one the first ARRL SSB
>handbooks was an excellent article on this subject, by the way.
>
>To avoid the problem I always try to keep my microphone gain down just
below
>the point where the ALC starts to show up on the rigs meter in the ALC
>position.
? Excellent. Schmuckoid operators seem to believe that something is
wrong unless the ALC meter is reading half scale.
> I will still get maximum pep output but a little less compression
>from the ALC. Remember the COLLINS rigs that had dual ALC constants? They
>had a little compression from the ALC too.
As I recall, in the Collins rigs with 6146 finals (and the TS830S) ALC
voltage was created by the grid drawing current. .
>
>My guess is, that running your transceiver as an exciter ( output level
>adjusted in the menu) or barefoot - the spike will always be there. An
>engeneering feedback problem no doubt. Delay in those modern very selective
>filters? Or in the multifilters used when hf clipping is used? Or wrong
time
>constants in the AGC loop? Too much or to little gain in the stages
>controlled by the ALC? I am not an specialist but will try to look into my
>old SSB handbooks from COLLINS. And I am sure there is somebody om amps who
>has dealt with this old problem and knows the answers?
>
>In 1958, my old 75A4 had a similar problem. There was always an overshoot
>before the AGC set in on strong signals. For some reasons, there was too
>much IF gain, I remember. Even the famous 51S1 has a very bad AGC on SSB:
>LA8AK wrote an article how to fix this, by the way.
>
>Hej daa de Hans SM5KI
>
>
>----------
>>Från: "Ian White, G3SEK" <G3SEK@ifwtech.demon.co.uk>
>>Till: amps@contesting.com
>>Ämne: Re: [AMPS] RE: ALC
>>Datum: ons 16 feb 2000 22.00
>>
>
>>
>>Rich Measures wrote:
>>
>>>>. Over 24 hours, the gain varies
>>>>somewhat and it's asking for trouble to have all the ops keep tweaking
the
>>>>mic gain.
>>>
>>>Amen. A high percentage of contest men seem to be infected with terminal
>>>''Pump Up the Volume'' disease -- much like CBers.
>>>
>>In simpler days with simpler rigs, a neat trick was to disconnect the
>>front-panel mic gain control and to preset the mic gain internally.
>>
>>The other essential part of the plot was to pretend that the mic gain
>>knob still worked, and to give all the contest ops the usual lecture
>>about how it had been carefully adjusted, and they ABSOLUTELY MUST NOT
>>touch it. That kept most people fooled for the whole weekend!
>>
>>73 from Ian G3SEK Editor, 'The VHF/UHF DX Book'
>> 'In Practice' columnist for RadCom (RSGB)
>> http://www.ifwtech.demon.co.uk/g3sek
>>
>>--
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>>
>>
>
>--
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>
>
- Rich..., 805.386.3734, www.vcnet.com/measures.
end
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