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KPA1500 / K3 Mystery

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ockmrzr

KPA1500 / K3 Mystery

I made a recent change to the "Band Change-> STBY" setting on the KPA1500,
changing from NO to YES. I did this to ensure the AMP doesn't have any wild
SWR or PWR spikes before the ATU has a chance to "remember" it's setting
after a band change.

Issue: When switching the AMP from OPER to STBY, the K3 is supposed to
switch from the drive power setting (~25 watts) in OPER, to 100 watts in
STBY, it does not, it remains at the drive power setting. I am 99% sure I
have all the cabling and settings set correctly in the K3 and KPA1500. I
went through and manually reset the power settings on each band to let the
K3 and KPA1500 "re-learn" the change made, however, still no joy.

Jim, W6YA, and I have been going back and forth, however neither of us have
had any luck.

Do you KPA1500/K3 owners out there have any ideas or suggestions?

73 de Bruce, N7TY

Yuma, AZ

www.qsl.net/n7ty <http://www.qsl.net/n7ty>

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Dick Dievendorff-4

Re: KPA1500 / K3 Mystery

There is a required K3 enabling menu selection, something like per band power setting. It’s the same menu item that allows you to dial 20 watts for 20 meters, 30 watts for 30 meters, and have those choices retained as you move from band to band.

The amp status messages go over AUXBUS, a wire in the 15-pin ACC cable. Is that OK? Does the K3 VFO frequency show up in the KPA1500 XCVR FREQ status screen as the VFO is moved? That K3 VFO frequency info flows over the same AUXBUS wire.

73 de Dick, K6KR

> On Oct 18, 2020, at 06:34, [hidden email] wrote:
>
> I made a recent change to the "Band Change-> STBY" setting on the KPA1500,
> changing from NO to YES. I did this to ensure the AMP doesn't have any wild
> SWR or PWR spikes before the ATU has a chance to "remember" it's setting
> after a band change.
>
>
>
> Issue: When switching the AMP from OPER to STBY, the K3 is supposed to
> switch from the drive power setting (~25 watts) in OPER, to 100 watts in
> STBY, it does not, it remains at the drive power setting. I am 99% sure I
> have all the cabling and settings set correctly in the K3 and KPA1500. I
> went through and manually reset the power settings on each band to let the
> K3 and KPA1500 "re-learn" the change made, however, still no joy.
>
>
>
> Jim, W6YA, and I have been going back and forth, however neither of us have
> had any luck.
>
>
>
> Do you KPA1500/K3 owners out there have any ideas or suggestions?
>
>
>
> 73 de Bruce, N7TY
>
> Yuma, AZ
>
> www.qsl.net/n7ty <http://www.qsl.net/n7ty>
>
>
>
> ______________________________________________________________
> 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
> Message delivered to [hidden email]

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ockmrzr

Re: KPA1500 / K3 Mystery

In reply to this post by ockmrzr

YES, when switching the KPA1500 between OPER and STBY, the K3 displays the
messages "KPA500 OPERATE" and "KPA500 STANDBY", depending.

YES, the K3 is set CONFIG: POWER SET is Per Band.

YES, when in STBY on the KPA1500, I set the "no amp" power to 100 watts, and
when in OPER, I set drive level per band; usually less than 30 watts, which
gets close to the legal limit.

Still the same results as described below.

73 de Bruce, N7TY

Yuma, AZ

<http://www.qsl.net/n7ty> www.qsl.net/n7ty

From: [hidden email] <[hidden email]>
Sent: October 18, 2020 06:32
To: '[hidden email]' <[hidden email]>
Subject: KPA1500 / K3 Mystery

I made a recent change to the "Band Change-> STBY" setting on the KPA1500,
changing from NO to YES. I did this to ensure the AMP doesn't have any wild
SWR or PWR spikes before the ATU has a chance to "remember" it's setting
after a band change.

Issue: When switching the AMP from OPER to STBY, the K3 is supposed to
switch from the drive power setting (~25 watts) in OPER, to 100 watts in
STBY, it does not, it remains at the drive power setting. I am 99% sure I
have all the cabling and settings set correctly in the K3 and KPA1500. I
went through and manually reset the power settings on each band to let the
K3 and KPA1500 "re-learn" the change made, however, still no joy.

Jim, W6YA, and I have been going back and forth, however neither of us have
had any luck.

Do you KPA1500/K3 owners out there have any ideas or suggestions?

73 de Bruce, N7TY

Yuma, AZ

www.qsl.net/n7ty <http://www.qsl.net/n7ty>

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Elecraft mailing list

Re: KPA1500 / K3 Mystery

Might you have set the Normal power for the band to low power? There are two power levels, after all. We tend to pay attention to the low power setting for the KPA usage, but it is also quite possible to set the Normal (KPA on STBY) to a low level as well. That would get the effect you see.

73!
Jack, W6FB

> On Oct 18, 2020, at 9:28 AM, [hidden email] wrote:
>
> YES, when switching the KPA1500 between OPER and STBY, the K3 displays the
> messages "KPA500 OPERATE" and "KPA500 STANDBY", depending.
>
>
>
> YES, the K3 is set CONFIG: POWER SET is Per Band.
>
>
>
> YES, when in STBY on the KPA1500, I set the "no amp" power to 100 watts, and
> when in OPER, I set drive level per band; usually less than 30 watts, which
> gets close to the legal limit.
>
>
>
> Still the same results as described below.
>
>
>
> 73 de Bruce, N7TY
>
> Yuma, AZ
>
> <http://www.qsl.net/n7ty> www.qsl.net/n7ty
>
>
>
> From: [hidden email] <[hidden email]>
> Sent: October 18, 2020 06:32
> To: '[hidden email]' <[hidden email]>
> Subject: KPA1500 / K3 Mystery
>
>
>
> I made a recent change to the "Band Change-> STBY" setting on the KPA1500,
> changing from NO to YES. I did this to ensure the AMP doesn't have any wild
> SWR or PWR spikes before the ATU has a chance to "remember" it's setting
> after a band change.
>
>
>
> Issue: When switching the AMP from OPER to STBY, the K3 is supposed to
> switch from the drive power setting (~25 watts) in OPER, to 100 watts in
> STBY, it does not, it remains at the drive power setting. I am 99% sure I
> have all the cabling and settings set correctly in the K3 and KPA1500. I
> went through and manually reset the power settings on each band to let the
> K3 and KPA1500 "re-learn" the change made, however, still no joy.
>
>
>
> Jim, W6YA, and I have been going back and forth, however neither of us have
> had any luck.
>
>
>
> Do you KPA1500/K3 owners out there have any ideas or suggestions?
>
>
>
> 73 de Bruce, N7TY
>
> Yuma, AZ
>
> www.qsl.net/n7ty <http://www.qsl.net/n7ty>
>
>
>
> ______________________________________________________________
> 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
> Message delivered to [hidden email]

David Box-2

Re: KPA1500 / K3 Mystery

In reply to this post by ockmrzr

Bruce

My system works with no issues.

I originally had some problems due to external software and macros I had
created that used the PC command to set power for different modes. The
K3 stores the last power used per band when either in OP or STBY with
the KPA1500, if you are getting the messages showing that the K3
recognizes the change in KPA operating mode then my only question is are
you using any software or have macros that might be changing power
without you knowing. I had to take all the PC commands out of my macros
for safety.

If all you say is correct (not doubting) and you are getting the
messages, not using any software or macros then only suggestion is to
contact support.

de Dave K5MWR

On 10/18/2020 11:28, [hidden email] wrote:

> YES, when switching the KPA1500 between OPER and STBY, the K3 displays the
> messages "KPA500 OPERATE" and "KPA500 STANDBY", depending.
>
>
>
> YES, the K3 is set CONFIG: POWER SET is Per Band.
>
>
>
> YES, when in STBY on the KPA1500, I set the "no amp" power to 100 watts, and
> when in OPER, I set drive level per band; usually less than 30 watts, which
> gets close to the legal limit.
>
>
>
> Still the same results as described below.
>
>
>
> 73 de Bruce, N7TY
>
> Yuma, AZ
>
> <http://www.qsl.net/n7ty> www.qsl.net/n7ty
>
>
>
> From: [hidden email] <[hidden email]>
> Sent: October 18, 2020 06:32
> To: '[hidden email]' <[hidden email]>
> Subject: KPA1500 / K3 Mystery
>
>
>
> I made a recent change to the "Band Change-> STBY" setting on the KPA1500,
> changing from NO to YES. I did this to ensure the AMP doesn't have any wild
> SWR or PWR spikes before the ATU has a chance to "remember" it's setting
> after a band change.
>
>
>
> Issue: When switching the AMP from OPER to STBY, the K3 is supposed to
> switch from the drive power setting (~25 watts) in OPER, to 100 watts in
> STBY, it does not, it remains at the drive power setting. I am 99% sure I
> have all the cabling and settings set correctly in the K3 and KPA1500. I
> went through and manually reset the power settings on each band to let the
> K3 and KPA1500 "re-learn" the change made, however, still no joy.
>
>
>
> Jim, W6YA, and I have been going back and forth, however neither of us have
> had any luck.
>
>
>
> Do you KPA1500/K3 owners out there have any ideas or suggestions?
>
>
>
> 73 de Bruce, N7TY
>
> Yuma, AZ
>
> www.qsl.net/n7ty <http://www.qsl.net/n7ty>
>
>
>
> ______________________________________________________________
> 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
> Message delivered to [hidden email]
>

Elecraft mailing list

Re: KPA1500 / K3 Mystery

In reply to this post by Elecraft mailing list

Like K5MWR, my K3 & KPA1500 work correctly with the K3 going to the alternate power setting when the 1500 is switched in Standby.

K3: Firmware 5.67 Power Set per Band; Tuning power Normal.

KPA1500: Firmware 2.38 Band Change Standby = No.

Neither unit is connected to a computer for any control functions. The sole connection is an outboard analog to USB interface for the digi modes.

I'm open to checking any other settings that might illuminate.

GL - Steve WB6RSE

> On Oct 18, 2020, at 10:31 AM, Jack Brindle via Elecraft <[hidden email]> wrote:
>
> Might you have set the Normal power for the band to low power? There are two power levels, after all. We tend to pay attention to the low power setting for the KPA usage, but it is also quite possible to set the Normal (KPA on STBY) to a low level as well. That would get the effect you see.
>
> 73!
> Jack, W6FB
>
>
>> On Oct 18, 2020, at 9:28 AM, [hidden email] wrote:
>>
>> YES, when switching the KPA1500 between OPER and STBY, the K3 displays the
>> messages "KPA500 OPERATE" and "KPA500 STANDBY", depending.
>>
>>
>>
>> YES, the K3 is set CONFIG: POWER SET is Per Band.
>>
>>
>>
>> YES, when in STBY on the KPA1500, I set the "no amp" power to 100 watts, and
>> when in OPER, I set drive level per band; usually less than 30 watts, which
>> gets close to the legal limit.
>>
>>
>>
>> Still the same results as described below.
>>
>>
>>
>> 73 de Bruce, N7TY
>>
>> Yuma, AZ
>>
>> <http://www.qsl.net/n7ty> www.qsl.net/n7ty
>>
>>
>>
>> From: [hidden email] <[hidden email]>
>> Sent: October 18, 2020 06:32
>> To: '[hidden email]' <[hidden email]>
>> Subject: KPA1500 / K3 Mystery
>>
>>
>>
>> I made a recent change to the "Band Change-> STBY" setting on the KPA1500,
>> changing from NO to YES. I did this to ensure the AMP doesn't have any wild
>> SWR or PWR spikes before the ATU has a chance to "remember" it's setting
>> after a band change.
>>
>>
>>
>> Issue: When switching the AMP from OPER to STBY, the K3 is supposed to
>> switch from the drive power setting (~25 watts) in OPER, to 100 watts in
>> STBY, it does not, it remains at the drive power setting. I am 99% sure I
>> have all the cabling and settings set correctly in the K3 and KPA1500. I
>> went through and manually reset the power settings on each band to let the
>> K3 and KPA1500 "re-learn" the change made, however, still no joy.
>>
>>
>>
>> Jim, W6YA, and I have been going back and forth, however neither of us have
>> had any luck.
>>
>>
>>
>> Do you KPA1500/K3 owners out there have any ideas or suggestions?
>>
>>
>>
>> 73 de Bruce, N7TY
>>
>> Yuma, AZ
>>
>> www.qsl.net/n7ty <http://www.qsl.net/n7ty>
>>
>>
>>
>> ______________________________________________________________
>> 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
>> Message delivered to [hidden email]
>
> ______________________________________________________________
> 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
> Message delivered to [hidden email]

Bob Wilson, N6TV

Re: KPA1500 / K3 Mystery

In reply to this post by ockmrzr

Bruce,

What is the firmware version of your KPA1500? 2.48 is the latest. There
was also a change in version 2.38, almost a year ago, that could fix the
issue for you:

02.38 11/4/2019 (Production 12/3/2019)
⦁ Switch to STBY if BAND CHANGE->STBY is enabled and the frequency (from
XCVR or TX count) is below the amp's frequency range
⦁ Wait longer after band change to inform K3 that KPA1500 has switched to
STBY when BANDCHANGE->STBY is YES

73,
Bob, N6TV

On Sun, Oct 18, 2020 at 9:30 AM <[hidden email]> wrote:

> YES, when switching the KPA1500 between OPER and STBY, the K3 displays the
> messages "KPA500 OPERATE" and "KPA500 STANDBY", depending.
>
>
>
> YES, the K3 is set CONFIG: POWER SET is Per Band.
>
>
>
> YES, when in STBY on the KPA1500, I set the "no amp" power to 100 watts,
> and
> when in OPER, I set drive level per band; usually less than 30 watts, which
> gets close to the legal limit.
>
>
>
> Still the same results as described below.
>
>
>
> 73 de Bruce, N7TY
>
> Yuma, AZ
>
> <http://www.qsl.net/n7ty> www.qsl.net/n7ty
>
>
>
> From: [hidden email] <[hidden email]>
> Sent: October 18, 2020 06:32
> To: '[hidden email]' <[hidden email]>
> Subject: KPA1500 / K3 Mystery
>
>
>
> I made a recent change to the "Band Change-> STBY" setting on the KPA1500,
> changing from NO to YES. I did this to ensure the AMP doesn't have any
> wild
> SWR or PWR spikes before the ATU has a chance to "remember" it's setting
> after a band change.
>
>
>
> Issue: When switching the AMP from OPER to STBY, the K3 is supposed to
> switch from the drive power setting (~25 watts) in OPER, to 100 watts in
> STBY, it does not, it remains at the drive power setting. I am 99% sure I
> have all the cabling and settings set correctly in the K3 and KPA1500. I
> went through and manually reset the power settings on each band to let the
> K3 and KPA1500 "re-learn" the change made, however, still no joy.
>
>
>
> Jim, W6YA, and I have been going back and forth, however neither of us have
> had any luck.
>
>
>
> Do you KPA1500/K3 owners out there have any ideas or suggestions?
>
>
>
> 73 de Bruce, N7TY
>
> Yuma, AZ
>
> www.qsl.net/n7ty <http://www.qsl.net/n7ty>
>
>
>
> ______________________________________________________________
> 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
> Message delivered to [hidden email]
>

Elecraft mailing list

Re: KPA1500 / K3 Mystery

In reply to this post by Elecraft mailing list

KPA1500 F/W updated to 2.48 (tks N6TV). Operation as expected. K3 PO changes correctly when the Amp is switched in and out of standby.

73 - Steve WB6RSE

> On Oct 18, 2020, at 10:56 AM, Steve Lawrence via Elecraft <[hidden email]> wrote:
>
> Like K5MWR, my K3 & KPA1500 work correctly with the K3 going to the alternate power setting when the 1500 is switched in Standby.
>
> K3: Firmware 5.67 Power Set per Band; Tuning power Normal.
>
> KPA1500: Firmware 2.38 Band Change Standby = No.
>
> Neither unit is connected to a computer for any control functions. The sole connection is an outboard analog to USB interface for the digi modes.
>
> I'm open to checking any other settings that might illuminate.
>
> GL - Steve WB6RSE
>
>> On Oct 18, 2020, at 10:31 AM, Jack Brindle via Elecraft <[hidden email]> wrote:
>>
>> Might you have set the Normal power for the band to low power? There are two power levels, after all. We tend to pay attention to the low power setting for the KPA usage, but it is also quite possible to set the Normal (KPA on STBY) to a low level as well. That would get the effect you see.
>>
>> 73!
>> Jack, W6FB
>>
>>
>>> On Oct 18, 2020, at 9:28 AM, [hidden email] wrote:
>>>
>>> YES, when switching the KPA1500 between OPER and STBY, the K3 displays the
>>> messages "KPA500 OPERATE" and "KPA500 STANDBY", depending.
>>>
>>>
>>>
>>> YES, the K3 is set CONFIG: POWER SET is Per Band.
>>>
>>>
>>>
>>> YES, when in STBY on the KPA1500, I set the "no amp" power to 100 watts, and
>>> when in OPER, I set drive level per band; usually less than 30 watts, which
>>> gets close to the legal limit.
>>>
>>>
>>>
>>> Still the same results as described below.
>>>
>>>
>>>
>>> 73 de Bruce, N7TY
>>>
>>> Yuma, AZ
>>>
>>> <http://www.qsl.net/n7ty> www.qsl.net/n7ty
>>>
>>>
>>>
>>> From: [hidden email] <[hidden email]>
>>> Sent: October 18, 2020 06:32
>>> To: '[hidden email]' <[hidden email]>
>>> Subject: KPA1500 / K3 Mystery
>>>
>>>
>>>
>>> I made a recent change to the "Band Change-> STBY" setting on the KPA1500,
>>> changing from NO to YES. I did this to ensure the AMP doesn't have any wild
>>> SWR or PWR spikes before the ATU has a chance to "remember" it's setting
>>> after a band change.
>>>
>>>
>>>
>>> Issue: When switching the AMP from OPER to STBY, the K3 is supposed to
>>> switch from the drive power setting (~25 watts) in OPER, to 100 watts in
>>> STBY, it does not, it remains at the drive power setting. I am 99% sure I
>>> have all the cabling and settings set correctly in the K3 and KPA1500. I
>>> went through and manually reset the power settings on each band to let the
>>> K3 and KPA1500 "re-learn" the change made, however, still no joy.
>>>
>>>
>>>
>>> Jim, W6YA, and I have been going back and forth, however neither of us have
>>> had any luck.
>>>
>>>
>>>
>>> Do you KPA1500/K3 owners out there have any ideas or suggestions?
>>>
>>>
>>>
>>> 73 de Bruce, N7TY
>>>
>>> Yuma, AZ
>>>
>>> www.qsl.net/n7ty <http://www.qsl.net/n7ty>
>>>
>>>
>>>
>>> ______________________________________________________________
>>> 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
>>> Message delivered to [hidden email]
>>
>> ______________________________________________________________
>> 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
>> Message delivered to [hidden email]
>
> ______________________________________________________________
> 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
> Message delivered to [hidden email]

Jim McCook W6YA

Re: KPA1500 / K3 Mystery

In reply to this post by ockmrzr

Bruce, I remember that one time I redid all my tuner settings on each
band and the STBY power was then reduced to the same value as the drive
power. I had to set each band back to 100w in STBY. That solved the
problem. Check it out. It's a per-band setting. 73, Jim W6YA
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w4sc-2

Re: KPA1500 / K3 Mystery

In reply to this post by ockmrzr

Jim,

What were the actions taken before you performed the re-training. Did you CLEAR all of the ‘bins’?

Ben W4SC.

Sent from Mail for Windows 10

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Jim McCook W6YA

Re: KPA1500 / K3 Mystery

In reply to this post by ockmrzr

Ben, The process I use is to first clear all the tuner settings on the
band I'm using. I go to STBY and hit ATU TUNE. Low power is applied to
start the search. When I first got the amp I did this when in OPER, but
even with low drive power I kept getting faults due to initially high
SWR. Recently during a trace working with Dick he noticed intervals of
very high drive power... up to 60w, which means the K3 ramps up power
output at times. It's complex. Jim W6YA
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Elecraft mailing list

Re: KPA1500 / K3 Mystery

In reply to this post by ockmrzr

Bruce;

Did you ever resolve the issue?

The KPA500 and KPA1500 send events to the K3, not commands. The distinction is important - an event simply reports a state change in the amplifier. It is up to the K3 to decide what to do in response, if anything.
Thus when tapping a and button the KPA simply sends an event indicate that the button had been tapped, the K3 receives that and decides to do a band switch (if needed).
The fact that the K3 is indicating a response (in the VFO B display) says the K3 is indeed receiving the event properly. That means the KPA1500 is working properly, so the issue is in the K3.

Since the K3 sets the correct power for the KPA OP mode, it should be expected the the K3 is also selecting the high power setting when the KPA indicates that it is in STBY mode. The is the same power level that would be used if the K3 is powered up with the KPA left turned off. From personal experience I have many times found the power not to be what I expected after some special operating activity, like Field Day where we run just 5 watts. Turning the Power knob usually fixes the problem quite nicely.

73!
Jack, W6FB
Elecraft Engineering

k6dgw

Re: KPA1500 / K3 Mystery

I'll second Jack's observation Bruce. "Most" of the time, the K3
switches power levels properly ... but, the key lies in Jack's
description of how it works. The K3 gets notice of "events" from the
KPA which treats the notices as "fire and forget." The event causes the
K3 to take some action(s) and go to some state. It seems to be great at
that. It also needs to remember that state [conceptually, "KPA in
standby"] regardless of what goes on thereafter. It seems there are
things you can do after putting the KPA in off or standby that foul up
this state memory. With a background in aircraft systems for the
military, the peripheral fire and forget mode is a non-starter for me.
I just developed the habit of always checking the K3 PWR OUT setting
before transmitting.

73,

Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

On 10/20/2020 3:08 PM, Jack Brindle via Elecraft wrote:

> Bruce;
>
> Did you ever resolve the issue?
>
> The KPA500 and KPA1500 send events to the K3, not commands. The distinction is important - an event simply reports a state change in the amplifier. It is up to the K3 to decide what to do in response, if anything.
> Thus when tapping a and button the KPA simply sends an event indicate that the button had been tapped, the K3 receives that and decides to do a band switch (if needed).
> The fact that the K3 is indicating a response (in the VFO B display) says the K3 is indeed receiving the event properly. That means the KPA1500 is working properly, so the issue is in the K3.
>
> Since the K3 sets the correct power for the KPA OP mode, it should be expected the the K3 is also selecting the high power setting when the KPA indicates that it is in STBY mode. The is the same power level that would be used if the K3 is powered up with the KPA left turned off. From personal experience I have many times found the power not to be what I expected after some special operating activity, like Field Day where we run just 5 watts. Turning the Power knob usually fixes the problem quite nicely.
>
> 73!
> Jack, W6FB
> Elecraft Engineering
>