K2/100 and external ALC from amplifier

[Peter Bacon]

I am currently using my K2/100 to drive a linear amplifier (Yaesu Quadra).
I would like to use the ALC output voltage from the amplifier to control the
output from my K2/100.
Has anyone managed to do this, and any recommendations?
Thanks
Peter

___________________
Peter Bacon
www.g3zss.co.uk
www.oceanfone.com
 


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[dj7mgq]

> use the ALC output voltage from the amplifier to control

This may not be such a good idea ...

Take a look at:  SM 5 BSZ - The abominable ALC.
http://www.nitehawk.com/sm5bsz/dynrange/alc.htm

----- Original Message -----
From: "Peter Bacon" <[hidden email]>
To: <[hidden email]>
Sent: Monday, February 13, 2006 11:34 AM
Subject: [Elecraft] K2/100 and external ALC from amplifier


I am currently using my K2/100 to drive a linear amplifier (Yaesu
Quadra).
I would like to use the ALC output voltage from the amplifier to
control the
output from my K2/100.
Has anyone managed to do this, and any recommendations?
Thanks
Peter

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[Don Wilhelm-3]

Peter,

Not practical - you will have to be satisfied with controlling the level of
the drive to the linear.

In most cases, using ALC is not a good idea IMHO because it is normally set
to be an indicator of gain compression which is another way of saying
'beginning to operate in a non-linear region' - so operating by depending on
ALC is a recipe for creating distortion.  As a parallel, you may want to
consider why operators using PSK31 and other digital modes are instructed to
opeate the equipment at a level below where ALC begins to operate to assure
a good IMD figure - if ther is ALC action, distortion is occurring.

The KPA100 uses a wattmeter at the output and communicates this information
to the base K2 uP then uses that information to control the BFO injection in
the K2 in order to control the power output.  I would guess (but I don't
know) that the 'to be announced' Elecraft linear will use a similar scheme
rather than using the ALC method to achieve output power control and assure
that the linear remains linear.

73,
Don W3FPR

> -----Original Message-----
>
> I am currently using my K2/100 to drive a linear amplifier (Yaesu Quadra).
> I would like to use the ALC output voltage from the amplifier to
> control the
> output from my K2/100.
> Has anyone managed to do this, and any recommendations?
> Thanks
> Peter
>
> ___________________
> Peter Bacon
> www.g3zss.co.uk
> www.oceanfone.com
>  
>
>
> _______________________________________________
> Elecraft mailing list
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> You must be a subscriber to post to the list.
> Subscriber Info (Addr. Change, sub, unsub etc.):
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