[Elecraft] ALC implementation

[K9MA]

I like to think of ALC as receiver AGC in reverse. Done properly, it 
results in minimal distortion while keeping the signal level nearly 
constant.  As far as I can tell, commercial transceivers have all been 
doing this pretty well for a long time.

What I've never been able to figure out is why it's so hard to close the 
ALC loop around an external amplifier. If it works with the 100 W 
amplifier built into the transceiver, why won't it work with a bigger 
amplifier? (And it seems about universally agreed that it won't.)

73,
Scott K9MA


On 7/12/2019 23:32, Wes wrote:
> You do know that the K3(S) uses a slow ALC system for power control 
> don't you?
>
> Wes  N7WS
>
> On 7/12/2019 8:53 PM, Brian Denley wrote:
>> Nothing when that’s what you want.  But using ALC to control xcvr 
>> power is uncontrolled compression that may or may not be desired.
>>
>> Brian
>> KB1VBF
>> Sent from my iPad
>>
>>> On Jul 12, 2019, at 4:09 PM, Wes <wes_n7ws at triconet.org> wrote:
>>>
>>> And what exactly is the problem with compression?  It's used all 
>>> over the place.
>>>
>>> Wes  N7WS
>>>
>>>> On 6/28/2019 11:38 AM, Brian Denley wrote:
>>>> I have always thought that ALC is not appropriate for power 
>>>> control.  It’s a protection system.  Over use of ALC acts like 
>>>> compression.  No?
>>>>
>>>> Brian
>>>> KB1VBF
>>>> Sent from my iPad
>>> ______________________________________________________________ 

-- 
Scott  K9MA

k9ma at sdellington.us