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ALC control of W6PQL amp from my K3

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Bob KD7YZ

ALC control of W6PQL amp from my K3

Wondering how to do this.

I see a cable on https://www.arraysolutions.com/k3alc

A K3 ALC cable ...

or any other ideas ?

I have a W6PQL 2m SSPA with an ALC input on the back

many thanks.

--
73
Bob KD7YZ
AMSAT LM #901

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Don Wilhelm

Re: ALC control of W6PQL amp from my K3

Bob,

It is important to understand that ALC does not control the amplifier,
it is an attempt by the amplifier to control the transceiver.

ALC is sent FROM the amplifier in an attempt to control the power of the
transceiver.

Used indiscriminately, that will cause distortion in the driving transciver.

Elecraft does not recommend the use of ALC for power control because of
that. Set the power output of the transceiver to drive the amplifier
properly and adjust the amplifier ALC to produce no ALC at that point.
If the amplifier has fault detection, then ALC can be used to drop input
power if a fault occurs - that is the only legitimate use of ALC.

So in many cases, an ALC connection is not needed.

73,
Don W3FPR

On 3/8/2019 9:11 PM, Bob KD7YZ wrote:

> Wondering how to do this.
>
> I see a cable on https://www.arraysolutions.com/k3alc
>
> A K3 ALC cable ...
>
> or any other ideas ?
>
> I have a W6PQL 2m SSPA with an ALC input on the back
>
>
> many thanks.
>
>
> --
> 73
> Bob KD7YZ
> AMSAT LM #901
>

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KENT TRIMBLE

Re: ALC control of W6PQL amp from my K3

Along with this, it should be noted (especially for new Amateurs) that . . .

Don is correct (always is) concerning the non-employment of ALC with
respect to Elecraft transceivers which produce power differently from
other brands. On this reflector, the recommendation not to use ALC
pertains solely to Elecraft products.

However, many Elecraft owners own and operate other brands of
transceivers and amplifiers. When using those other brands, the
instructions provided in the transceiver manual AND the instructions
provided in the amplifier manual about using ALC should be followed,
especially with solid state amplifiers. Those instructions often differ
from those recommended by Elecraft. Some brands require a one-time ALC
calibration procedure prior to use. Once properly configured, they are
usually free of the distortion Don rightfully talks about.

As a friend of mine puts it, the ALC controversy borders on being a
religious issue.

73,

Kent K9ZTV

On 3/9/2019 11:01 AM, Don Wilhelm wrote:

> Bob,
>
> It is important to understand that ALC does not control the amplifier,
> it is an attempt by the amplifier to control the transceiver.
>
> ALC is sent FROM the amplifier in an attempt to control the power of
> the transceiver.
>
> Used indiscriminately, that will cause distortion in the driving
> transciver.
>
> Elecraft does not recommend the use of ALC for power control because
> of that. Set the power output of the transceiver to drive the
> amplifier properly and adjust the amplifier ALC to produce no ALC at
> that point. If the amplifier has fault detection, then ALC can be used
> to drop input power if a fault occurs - that is the only legitimate
> use of ALC.
>
> So in many cases, an ALC connection is not needed.
>
> 73,
> Don W3FPR
>
> On 3/8/2019 9:11 PM, Bob KD7YZ wrote:
>> Wondering how to do this.
>>
>> I see a cable on https://www.arraysolutions.com/k3alc
>>
>> A K3 ALC cable ...
>>
>> or any other ideas ?
>>
>> I have a W6PQL 2m SSPA with an ALC input on the back
>>
>>
>> many thanks.
>>
>>
>> --
>> 73
>> Bob KD7YZ
>> AMSAT LM #901
>>
> ______________________________________________________________
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>
>

---
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Bob McGraw - K4TAX

Re: ALC control of W6PQL amp from my K3

I would emphasize with the K3S and KPA500, if one follows the set-up
EXACTLY as described in the KPA500 manual page 16 & 17, and in the K3S
manual page 29 & 59, all will be well with the EXT ALC engaged.
Anything else will be a PICNIC problem.

I suggest the set-up be done with a 50 ohm resistive dummy load
connected to the amplifier.   Therefore any major deviation in output
load will then provide a margin of safety via the ALC. Correctly set-up
one can then observe any excessive drive applied to the amplifier or a
load which exceeds the recommended load range by an indication on the
transceiver ALC indicator.    This ONLY applies to the K3S and KPA500 as
described.

73

Bob, K4TAX

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Joe Subich, W4TV-4

Re: ALC control of W6PQL amp from my K3

In reply to this post by KENT TRIMBLE

On 2019-03-09 12:59 PM, KENT TRIMBLE wrote:
> Some brands require a one-time ALC calibration procedure prior to
> use. Once properly configured, they are usually free of the
> distortion Don rightfully talks about.

Regardless of "calibration" most non-Elecraft transceivers have
significant ALC related distortion whether one is using an amp
or not. Quite simply, most non-Elecraft transceivers develop
their ALC based on *excess drive* to the final amplifier (a carry-
over from tube based amplifiers where ALC was developed when the
tubes started to draw grid current as they moved from class AB1
to AB2) and run excess drive in order to do so.

The excess drive plus overdrive sensing creates a situation in which
some combination of IF amp, driver and final amplifier are operating
in the compression region *AND* the ALC time constant allows an initial
"overshoot" (or power "spike").

73,

... Joe, W4TV

On 2019-03-09 12:59 PM, KENT TRIMBLE wrote:

> Along with this, it should be noted (especially for new Amateurs) that .
> . .
>
> Don is correct (always is) concerning the non-employment of ALC with
> respect to Elecraft transceivers which produce power differently from
> other brands. On this reflector, the recommendation not to use ALC
> pertains solely to Elecraft products.
>
> However, many Elecraft owners own and operate other brands of
> transceivers and amplifiers. When using those other brands, the
> instructions provided in the transceiver manual AND the instructions
> provided in the amplifier manual about using ALC should be followed,
> especially with solid state amplifiers. Those instructions often differ
> from those recommended by Elecraft. Some brands require a one-time ALC
> calibration procedure prior to use. Once properly configured, they are
> usually free of the distortion Don rightfully talks about.
>
> As a friend of mine puts it, the ALC controversy borders on being a
> religious issue.
>
> 73,
>
> Kent K9ZTV
>
>
> On 3/9/2019 11:01 AM, Don Wilhelm wrote:
>> Bob,
>>
>> It is important to understand that ALC does not control the amplifier,
>> it is an attempt by the amplifier to control the transceiver.
>>
>> ALC is sent FROM the amplifier in an attempt to control the power of
>> the transceiver.
>>
>> Used indiscriminately, that will cause distortion in the driving
>> transciver.
>>
>> Elecraft does not recommend the use of ALC for power control because
>> of that. Set the power output of the transceiver to drive the
>> amplifier properly and adjust the amplifier ALC to produce no ALC at
>> that point. If the amplifier has fault detection, then ALC can be used
>> to drop input power if a fault occurs - that is the only legitimate
>> use of ALC.
>>
>> So in many cases, an ALC connection is not needed.
>>
>> 73,
>> Don W3FPR
>>
>> On 3/8/2019 9:11 PM, Bob KD7YZ wrote:
>>> Wondering how to do this.
>>>
>>> I see a cable on https://www.arraysolutions.com/k3alc
>>>
>>> A K3 ALC cable ...
>>>
>>> or any other ideas ?
>>>
>>> I have a W6PQL 2m SSPA with an ALC input on the back
>>>
>>>
>>> many thanks.
>>>
>>>
>>> --
>>> 73
>>> Bob KD7YZ
>>> AMSAT LM #901
>>>

Elecraft mailing list

Re: ALC control of W6PQL amp from my K3

In reply to this post by Bob McGraw - K4TAX

As an example of how we feel about ALC with the K3 and KPA500, neither of my custom-made AUX-IO cables has the ALC pin (pin 15) connected. It is just not needed.
If the KPA500 needs to protect itself, it will.

73!
Jack, W6FB

> On Mar 9, 2019, at 10:23 AM, Bob McGraw K4TAX <[hidden email]> wrote:
>
> I would emphasize with the K3S and KPA500, if one follows the set-up EXACTLY as described in the KPA500 manual page 16 & 17, and in the K3S manual page 29 & 59, all will be well with the EXT ALC engaged. Anything else will be a PICNIC problem.
>
> I suggest the set-up be done with a 50 ohm resistive dummy load connected to the amplifier. Therefore any major deviation in output load will then provide a margin of safety via the ALC. Correctly set-up one can then observe any excessive drive applied to the amplifier or a load which exceeds the recommended load range by an indication on the transceiver ALC indicator. This ONLY applies to the K3S and KPA500 as described.
>
> 73
>
> Bob, K4TAX
>
>
>
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Jim Brown-10

Re: ALC control of W6PQL amp from my K3

In reply to this post by KENT TRIMBLE

On 3/9/2019 9:59 AM, KENT TRIMBLE wrote:
> As a friend of mine puts it, the ALC controversy borders on being a
> religious issue.

No, it does not. It is science. ALC should NEVER be used to set the
output power of a power amplifier, because doing so produces lots of
distortion (splatter, clicks). ALC should be used ONLY to protect the
power amp from damage in the event of problems in the antenna system or
operator error.

73, Jim K9YC

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Jim Brown-10

Re: ALC control of W6PQL amp from my K3

On 3/9/2019 12:57 PM, Bob McGraw K4TAX wrote:
> Yes and some brand(s) of radios are affectionately known as "click
> generators" being the result of they way they control power.

I wouldn't call that affection, but rather disgust. And I wouldn't blame
it entirely on how they control power.

Several years ago, I produced a study of ARRL Lab reviews of the CW
bandwidth of about 20 transceivers, including some of the most
expensive. The best (the cleanest) was the K3, followed by the Kenwood
TS590. The worst were Yaesu rigs, with Icom about half as bad.

The study is here. http://k9yc.com/TXNoise.pdf

Not included in the analysis are the current generation of Flex rigs,
which, when tested by ARRL Labs were pretty dirty, but made pretty clean
by new firmware released not much later. Also not included was the
improvement to the Yaesu rigs by new firmware released after I leaked a
preliminary version of my study to someone who I strongly suspected
would pass it along to the factory. :) The improvement is documented here.

http://k9yc.com/FTDX5000_Report.pdf

A primary contributor to excessive bandwidth is excessively fast
rise/fall time of keying, and the best rigs (the K3 and the Flex 6000
series) carefully shape keying to minimize CW bandwidth while
maintaining clearly defined keying. The worst rigs do none of that,
include controls that allow the user to change the rise/fall time, and
set a fast (worst) time as the default.

73, Jim K9YC

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John Simmons

Re: ALC control of W6PQL amp from my K3

Jim and all:

I have been a ham and avid CW op since 1970. I remember the Drake twins
having a wonderful sound on CW, an almost bell-like sound. Has anyone
looked at the CW waveform of those old rigs compared to the new generation?

-John NI0K

> Jim Brown <mailto:[hidden email]>
> Saturday, March 09, 2019 3:34 PM
>
>
> I wouldn't call that affection, but rather disgust. And I wouldn't
> blame it entirely on how they control power.
>
> Several years ago, I produced a study of ARRL Lab reviews of the CW
> bandwidth of about 20 transceivers, including some of the most
> expensive. The best (the cleanest) was the K3, followed by the Kenwood
> TS590. The worst were Yaesu rigs, with Icom about half as bad.
>
> The study is here. http://k9yc.com/TXNoise.pdf
>
> Not included in the analysis are the current generation of Flex rigs,
> which, when tested by ARRL Labs were pretty dirty, but made pretty
> clean by new firmware released not much later. Also not included was
> the improvement to the Yaesu rigs by new firmware released after I
> leaked a preliminary version of my study to someone who I strongly
> suspected would pass it along to the factory. :) The improvement is
> documented here.
>
> http://k9yc.com/FTDX5000_Report.pdf
>
> A primary contributor to excessive bandwidth is excessively fast
> rise/fall time of keying, and the best rigs (the K3 and the Flex 6000
> series) carefully shape keying to minimize CW bandwidth while
> maintaining clearly defined keying. The worst rigs do none of that,
> include controls that allow the user to change the rise/fall time, and
> set a fast (worst) time as the default.
>
> 73, Jim K9YC
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Jim Brown <mailto:[hidden email]>
> Saturday, March 09, 2019 2:38 PM
>
>
> No, it does not. It is science. ALC should NEVER be used to set the
> output power of a power amplifier, because doing so produces lots of
> distortion (splatter, clicks). ALC should be used ONLY to protect the
> power amp from damage in the event of problems in the antenna system
> or operator error.
>
> 73, Jim K9YC
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> KENT TRIMBLE <mailto:[hidden email]>
> Saturday, March 09, 2019 11:59 AM
> Along with this, it should be noted (especially for new Amateurs) that
> . . .
>
> Don is correct (always is) concerning the non-employment of ALC with
> respect to Elecraft transceivers which produce power differently from
> other brands. On this reflector, the recommendation not to use ALC
> pertains solely to Elecraft products.
>
> However, many Elecraft owners own and operate other brands of
> transceivers and amplifiers. When using those other brands, the
> instructions provided in the transceiver manual AND the instructions
> provided in the amplifier manual about using ALC should be followed,
> especially with solid state amplifiers. Those instructions often
> differ from those recommended by Elecraft. Some brands require a
> one-time ALC calibration procedure prior to use. Once properly
> configured, they are usually free of the distortion Don rightfully
> talks about.
>
> As a friend of mine puts it, the ALC controversy borders on being a
> religious issue.
>
> 73,
>
> Kent K9ZTV
>
>
>
>
>
>
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> https://www.avg.com
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> Don Wilhelm <mailto:[hidden email]>
> Saturday, March 09, 2019 11:01 AM
> Bob,
>
> It is important to understand that ALC does not control the amplifier,
> it is an attempt by the amplifier to control the transceiver.
>
> ALC is sent FROM the amplifier in an attempt to control the power of
> the transceiver.
>
> Used indiscriminately, that will cause distortion in the driving
> transciver.
>
> Elecraft does not recommend the use of ALC for power control because
> of that. Set the power output of the transceiver to drive the
> amplifier properly and adjust the amplifier ALC to produce no ALC at
> that point. If the amplifier has fault detection, then ALC can be used
> to drop input power if a fault occurs - that is the only legitimate
> use of ALC.
>
> So in many cases, an ALC connection is not needed.
>
> 73,
> Don W3FPR
>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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Dr. William J. Schmidt, II

Re: ALC control of W6PQL amp from my K3

In reply to this post by Jim Brown-10

The underlying reality is that if you analyze the input-output transfer function for a linear amplifier with ALC, the resulting transfer function is not linear. Thus you would expect all sorts of odd behaviors as the function changes order when ALC engages. Simple math.

Dr. William J. Schmidt - K9HZ J68HZ

email: [hidden email]

> On Mar 9, 2019, at 4:38 PM, Jim Brown <[hidden email]> wrote:
>
>> On 3/9/2019 9:59 AM, KENT TRIMBLE wrote:
>> As a friend of mine puts it, the ALC controversy borders on being a religious issue.
>
> No, it does not. It is science. ALC should NEVER be used to set the output power of a power amplifier, because doing so produces lots of distortion (splatter, clicks). ALC should be used ONLY to protect the power amp from damage in the event of problems in the antenna system or operator error.
>
> 73, Jim K9YC
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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Wes Stewart-2

Re: ALC control of W6PQL amp from my K3

In reply to this post by KENT TRIMBLE

Indeed. Folks who would never think to turn off the AGC in their receivers get
weak-kneed at the thought of AGC (ALC) being used in the transmit loop. In
"Fundamentals of SSB", Collins radio speaks of ALC (pp.7-10,11) without any
negativity, and in fact calls it a form of speech compression. As in many
things, the devil is in the details.

I suspect most of the Elecraft faithful would also be surprised to know that
their beloved K3s use internal ALC as well as digital power control. This is not
perfect, I've observed overshoot, power slowly increasing to set level and low
level power jitter*.

* You need a spectrum analyzer to see this and it's unlikely to be heard on the
air, but it's there.

Wes N7WS

On 3/9/2019 10:59 AM, KENT TRIMBLE wrote:
> ...
> As a friend of mine puts it, the ALC controversy borders on being a religious
> issue.
>
> 73,
>
> Kent K9ZTV

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John Simmons

Re: ALC control of W6PQL amp from my K3

Wes,

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.

73,
-John NI0K

> Wes <mailto:[hidden email]>
> Sunday, March 10, 2019 9:39 AM
> Indeed. Folks who would never think to turn off the AGC in their
> receivers get weak-kneed at the thought of AGC (ALC) being used in the
> transmit loop. In "Fundamentals of SSB", Collins radio speaks of ALC
> (pp.7-10,11) without any negativity, and in fact calls it a form of
> speech compression. As in many things, the devil is in the details.
>
> I suspect most of the Elecraft faithful would also be surprised to
> know that their beloved K3s use internal ALC as well as digital power
> control. This is not perfect, I've observed overshoot, power slowly
> increasing to set level and low level power jitter*.
>
> * You need a spectrum analyzer to see this and it's unlikely to be
> heard on the air, but it's there.
>
> Wes N7WS
>
>
>
> ______________________________________________________________
> Elecraft mailing list
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Jim Brown-10

Re: ALC control of W6PQL amp from my K3

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.

The earliest advice I've seen about this was in the user manual for the
Ten Tec Titan 425, designed around 1979, and using a pair of the same
3CX8007 triodes used in the 87A. The manual said that ALC output was
provided only for historical reasons, and advised against using it to
control output power.

When you look ONLY at output power, you miss the mess that ALC causes.
To see it, you must look at (or listen to) the transmitted frequency
spectrum. A P3 on a second radio, or an SDR receiver will clearly reveal
the splatter and clicks.

73, Jim K9YC

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Bob McGraw - K4TAX

Re: ALC control of W6PQL amp from my K3

And with my P3 or SDR when one closely examines a signal, the evidence of improper ALC usage or ALC overshoot is very prominent with many signals.

The sad thing is that it can be corrected with proper settings and usage. There is no need to occupy 10kHz of the band. And just listening to a signal usually doesn't disclose this nasty artifact.

Bob, K4TAX

Sent from my iPhone

> On Mar 10, 2019, at 2:02 PM, Jim Brown <[hidden email]> 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.
>
> The earliest advice I've seen about this was in the user manual for the Ten Tec Titan 425, designed around 1979, and using a pair of the same 3CX8007 triodes used in the 87A. The manual said that ALC output was provided only for historical reasons, and advised against using it to control output power.
>
> When you look ONLY at output power, you miss the mess that ALC causes. To see it, you must look at (or listen to) the transmitted frequency spectrum. A P3 on a second radio, or an SDR receiver will clearly reveal the splatter and clicks.
>
> 73, Jim K9YC
>
> ______________________________________________________________
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>

Don Wilhelm

Re: ALC control of W6PQL amp from my K3

In reply to this post by Jim Brown-10

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.
>
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John Simmons

Re: ALC control of W6PQL amp from my K3

I have seen overshoot in the TUNE mode.

-John NI0K

> Don Wilhelm <mailto:[hidden email]>
> Sunday, March 10, 2019 2:40 PM
> 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
>
>
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>
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> Jim Brown <mailto:[hidden email]>
> Sunday, March 10, 2019 2:02 PM
>
>
> 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.
>
> The earliest advice I've seen about this was in the user manual for
> the Ten Tec Titan 425, designed around 1979, and using a pair of the
> same 3CX8007 triodes used in the 87A. The manual said that ALC output
> was provided only for historical reasons, and advised against using it
> to control output power.
>
> When you look ONLY at output power, you miss the mess that ALC causes.
> To see it, you must look at (or listen to) the transmitted frequency
> spectrum. A P3 on a second radio, or an SDR receiver will clearly
> reveal the splatter and clicks.
>
> 73, Jim K9YC
>
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> John Simmons <mailto:[hidden email]>
> Sunday, March 10, 2019 1:34 PM
> Wes,
>
> 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.
>
> 73,
> -John NI0K
>
>
> ______________________________________________________________
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> Wes <mailto:[hidden email]>
> Sunday, March 10, 2019 9:39 AM
> Indeed. Folks who would never think to turn off the AGC in their
> receivers get weak-kneed at the thought of AGC (ALC) being used in the
> transmit loop. In "Fundamentals of SSB", Collins radio speaks of ALC
> (pp.7-10,11) without any negativity, and in fact calls it a form of
> speech compression. As in many things, the devil is in the details.
>
> I suspect most of the Elecraft faithful would also be surprised to
> know that their beloved K3s use internal ALC as well as digital power
> control. This is not perfect, I've observed overshoot, power slowly
> increasing to set level and low level power jitter*.
>
> * You need a spectrum analyzer to see this and it's unlikely to be
> heard on the air, but it's there.
>
> Wes N7WS
>
>
>
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Bill Frantz

Re: ALC control of W6PQL amp from my K3

In reply to this post by Don Wilhelm

What makes Don's excellend advice harder is that there may be as
many as 4 audio level controls between the computer and the
transmitter. (The one in the program, the OS's control, one on
the interface box (SignaLink), and the one on the radio.)

My solution is to have all but one, the one in the program, set
to constant values, so they can be quickly set.

73 Bill AE6JV

On 3/10/19 at 12:40 PM, [hidden email] (Don Wilhelm) wrote:

>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.

-----------------------------------------------------------------------
Bill Frantz | "The only thing we have to | Periwinkle
(408)356-8506 | fear is fear itself." - FDR | 16345
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www.pwpconsult.com | Inaugural address, 3/4/1933 | Los Gatos,
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Don Wilhelm

Re: ALC control of W6PQL amp from my K3

In reply to this post by John Simmons

TUNE is a bit different than normal operating. The power control is not
as tight.
I am speaking from my K2 experience, but the K3 has about the same power
control mechanism

73,
Don W3FPR

On 3/10/2019 5:03 PM, John Simmons wrote:
> I have seen overshoot in the TUNE mode.
>
> -John NI0K
>

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Wes Stewart-2

Re: ALC control of W6PQL amp from my K3

In reply to this post by Bill Frantz

True to a point. I would (and did) lose the SignaLink. I use my Lenovo
laptop's internal sound card, even with a K3S.

Wes N7WS

On 3/10/2019 2:16 PM, Bill Frantz wrote:
> What makes Don's excellend advice harder is that there may be as many as 4
> audio level controls between the computer and the transmitter. (The one in the
> program, the OS's control, one on the interface box (SignaLink), and the one
> on the radio.)
>
> My solution is to have all but one, the one in the program, set to constant
> values, so they can be quickly set.
>
> 73 Bill AE6JV

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Bill Frantz

Re: ALC control of W6PQL amp from my K3

I lost the SignaLink as well, but I think a lot of readers of
this list use one.

I currently use the internal "sound card" in my upgraded K3, or
a home brew interface based on a $5 sound card from Amazon on my KX3.

73 Bill AE6JV

On 3/10/19 at 2:40 PM, [hidden email] (Wes) wrote:

>True to a point. I would (and did) lose the SignaLink. I
>use my Lenovo laptop's internal sound card, even with a K3S.
>
>Wes N7WS
>
>On 3/10/2019 2:16 PM, Bill Frantz wrote:
>>What makes Don's excellend advice harder is that there may be
>>as many as 4 audio level controls between the computer and the
>>transmitter. (The one in the program, the OS's control, one on
>>the interface box (SignaLink), and the one on the radio.)
>>
>>My solution is to have all but one, the one in the program,
>>set to constant values, so they can be quickly set.
>>
>>73 Bill AE6JV

-------------------------------------------------------------------------
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CA 95032

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