[Elecraft] ALC control of W6PQL amp from my K3

[Don Wilhelm]

I am left wondering if some K3 users who are seeing "Overshoot" are 
actually seeing what is referred to as "Power Hunting".
That would occur mostly in Voice or DATA modes when the audio level is 
not set high enough.

With insufficient audio, the K3 can initially go up to the set power, 
and then will quickly settle back to a low power, and then gradually 
climb to the full power set by the power knob - that behavior is seldom 
seen in CW mode, but can be seen in DATA modes and Voice modes if the 
audio levels are not set correctly.

The cure for that behavior is to drive the audio as indicated in the 
manual.  For voice modes, adjust the MIC Gain to produce 5 to 7 bars on 
the ALC meter.
For DATA modes, adjust the audio levels to produce 4 bars solid with the 
5th bar flashing.

If your data mode application has a "POWER" slider, it is not properly 
named (complain to Joe Taylor) - it is just another audio level control.

The Elecraft transceivers control power differently than all other 
amateur transceivers, so ignore the common internet advice to control 
the power with the audio level.  Set the audio as indicated in my 
website article (same information is in the K3/K3S/KX3/KX2 manual) and 
adjust the desired power with the POWER knob.

Other transceivers may be able to use the audio level to control the 
output power, but Elecraft transceivers are different, do not "do it 
that a-way".

Look at the article on my website www.w3fpr.com.  Scroll down the left 
column and click to open the document.

BTW: The originator of this thread is now on the right track, I have 
exchanged several email messages with him (and I built his transverters).

73,
Don W3FPR

On 3/10/2019 3:02 PM, Jim Brown wrote:
> On 3/10/2019 11:34 AM, John Simmons wrote:
>> Once I got my LP100, I began to see the same behavior with my K3. This 
>> type of output anomaly is a huge reason to use ALC. 
> 
> I've had an LP100 in line for several years, always set to read peak 
> power, and the most overshoot I've seen from either of my two K3s is 
> less than 1 dB. The K3s are driving a pair of 87As, and I have NEVER 
> used ALC between rig and amp.
>