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K3 KPA3 bias adjust

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Jan Erik Holm

K3 KPA3 bias adjust

I find nothing about it in any manual. R11 on KPA3
I guess. What are the specifications for the bias
adjust?

73 Jim SM2EKM

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AC7AC

RE: K3 KPA3 bias adjust

CONTENTS DELETED

The author has deleted this message.

Jan Erik Holm

Re: K3 KPA3 bias adjust

Thanks Ron but I knew this already.

Probably have to write to K3support and ask,
however I´m very surprised nobody could answer
on the reflector.

Jim SM2EKM
----------------------
Ron D'Eau Claire wrote:

> Hello Jim:
>
> That pot, along with all the other trimmers in the K3, is adjusted at the
> factory. There are specific cautions against touching any of them in the
> field; all field adjustments are done in firmware.
>
> If you have a problem with the KPA3, suggest you post a message to
> [hidden email]. If an adjustment is needed that can be done in the
> field, one of the fellows there can give you specifics.
>
> Ron AC7AC
>
>
>
> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]] On Behalf Of Jan Erik Holm
> Sent: Saturday, January 03, 2009 6:55 AM
> To: [hidden email]
> Subject: [Elecraft] K3 KPA3 bias adjust
>
> I find nothing about it in any manual. R11 on KPA3
> I guess. What are the specifications for the bias
> adjust?
>
> 73 Jim SM2EKM
>
>

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Klaus Koppendorfer

AW: K3 KPA3 bias adjust

Locate the BIAS pot at the front of the KPA3, between the heat sink and the KPA3 shield. Note what the display current is in the VFO B readout when you tap the Display button and turn the VFO B knob to the current readout. In RX, it should be 1.0A or so. In XMIT (not TUNE), it should be about 1.90 to 2.0A when the Power knob is set to 12w or above so the KPA3 is made active (but there is no RF output since XMIT is used). Or you can press the PTT button but do not speak.

If there is much more current than this, set the BIAS pot to minimum (fully counter clockwise). Then tap XMIT (not TUNE) and note what the current is in VFO B's readout. Slowly turn up the BIAS pot until you see 400-500mA more current that was seen with the BIAS pot at minimum.

73
OE6KYG
KX1 244
K2 1331
K3 115

> -----Ursprüngliche Nachricht-----
> Von: [hidden email] [mailto:elecraft-
> [hidden email]] Im Auftrag von Jan Erik Holm
> Gesendet: Samstag, 03. Jänner 2009 19:35
> Cc: [hidden email]
> Betreff: Re: [Elecraft] K3 KPA3 bias adjust
>
> Thanks Ron but I knew this already.
>
> Probably have to write to K3support and ask,
> however I´m very surprised nobody could answer
> on the reflector.
>
> Jim SM2EKM
> ----------------------
> Ron D'Eau Claire wrote:
> > Hello Jim:
> >
> > That pot, along with all the other trimmers in the K3, is adjusted at
> the
> > factory. There are specific cautions against touching any of them in the
> > field; all field adjustments are done in firmware.
> >
> > If you have a problem with the KPA3, suggest you post a message to
> > [hidden email]. If an adjustment is needed that can be done in
> the
> > field, one of the fellows there can give you specifics.
> >
> > Ron AC7AC
> >
> >
> >
> > -----Original Message-----
> > From: [hidden email]
> > [mailto:[hidden email]] On Behalf Of Jan Erik Holm
> > Sent: Saturday, January 03, 2009 6:55 AM
> > To: [hidden email]
> > Subject: [Elecraft] K3 KPA3 bias adjust
> >
> > I find nothing about it in any manual. R11 on KPA3
> > I guess. What are the specifications for the bias
> > adjust?
> >
> > 73 Jim SM2EKM
> >
> >
>
> _______________________________________________
> Elecraft mailing list
> Post to: [hidden email]
> You must be a subscriber to post to the list.
> Subscriber Info (Addr. Change, sub, unsub etc.):
> http://mailman.qth.net/mailman/listinfo/elecraft
>
> Help: http://mailman.qth.net/subscribers.htm
> Elecraft web page: http://www.elecraft.com

Elecraft mailing list

Fwd: AW: K3 KPA3 bias adjust

Hi,

Forwarded a 2009 email exchange for your info. I have NOT tried this so
use with care and at your own risk.

Regards,

Mike VP8NO

-------- Forwarded Message --------
Subject: AW: [Elecraft] K3 KPA3 bias adjust
Date: Sat, 3 Jan 2009 19:46:55 +0100
From: Koppendorfer Klaus <[hidden email]>
To: Jan Erik Holm <[hidden email]>
CC: [hidden email] <[hidden email]>

Locate the BIAS pot at the front of the KPA3, between the heat sink and
the KPA3 shield. Note what the display current is in the VFO B readout
when you tap the Display button and turn the VFO B knob to the current
readout. In RX, it should be 1.0A or so. In XMIT (not TUNE), it should
be about 1.90 to 2.0A when the Power knob is set to 12w or above so the
KPA3 is made active (but there is no RF output since XMIT is used). Or
you can press the PTT button but do not speak.

If there is much more current than this, set the BIAS pot to minimum
(fully counter clockwise). Then tap XMIT (not TUNE) and note what the
current is in VFO B's readout. Slowly turn up the BIAS pot until you see
400-500mA more current that was seen with the BIAS pot at minimum.

73
OE6KYG
KX1 244
K2 1331
K3 115

ke9uw

Re: Fwd: AW: K3 KPA3 bias adjust

Thanks for the info. Using xmit for the low power amp and then going to the high power amp shows a difference of 1.05A. So my devices are showing about 500+ ma each. In the ball park.
Thanks so much for the reply.

Chuck Hawley
[hidden email]

Amateur Radio, KE9UW
aka Jack, BMW Motorcycles

________________________________
From: [hidden email] <[hidden email]> on behalf of Mike Harris via Elecraft <[hidden email]>
Sent: Thursday, March 7, 2019 5:43 AM
To: [hidden email]
Subject: [Elecraft] Fwd: AW: K3 KPA3 bias adjust

Hi,

Forwarded a 2009 email exchange for your info. I have NOT tried this so
use with care and at your own risk.

Regards,

Mike VP8NO

-------- Forwarded Message --------
Subject: AW: [Elecraft] K3 KPA3 bias adjust
Date: Sat, 3 Jan 2009 19:46:55 +0100
From: Koppendorfer Klaus <[hidden email]>
To: Jan Erik Holm <[hidden email]>
CC: [hidden email] <[hidden email]>

Locate the BIAS pot at the front of the KPA3, between the heat sink and
the KPA3 shield. Note what the display current is in the VFO B readout
when you tap the Display button and turn the VFO B knob to the current
readout. In RX, it should be 1.0A or so. In XMIT (not TUNE), it should
be about 1.90 to 2.0A when the Power knob is set to 12w or above so the
KPA3 is made active (but there is no RF output since XMIT is used). Or
you can press the PTT button but do not speak.

If there is much more current than this, set the BIAS pot to minimum
(fully counter clockwise). Then tap XMIT (not TUNE) and note what the
current is in VFO B's readout. Slowly turn up the BIAS pot until you see
400-500mA more current that was seen with the BIAS pot at minimum.

73
OE6KYG
KX1 244
K2 1331
K3 115

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Chuck, KE9UW

Don Wilhelm

Re: Fwd: AW: K3 KPA3 bias adjust

Chuck,

The instruction cited was for a 400-500 ma rise TOTAL (not per device).
So I conclude your bias is set too high or there is a problem in the
bias circuit.

73,
Don W3FPR

On 3/7/2019 9:31 AM, hawley, charles j jr wrote:

> Thanks for the info. Using xmit for the low power amp and then going to the high power amp shows a difference of 1.05A. So my devices are showing about 500+ ma each. In the ball park.
> Thanks so much for the reply.
>
> Chuck Hawley
> [hidden email]
>
> Amateur Radio, KE9UW
> aka Jack, BMW Motorcycles
>
> ________________________________
> From: [hidden email] <[hidden email]> on behalf of Mike Harris via Elecraft <[hidden email]>
> Sent: Thursday, March 7, 2019 5:43 AM
> To: [hidden email]
> Subject: [Elecraft] Fwd: AW: K3 KPA3 bias adjust
>
> Hi,
>
> Forwarded a 2009 email exchange for your info. I have NOT tried this so
> use with care and at your own risk.
>
> Regards,
>
> Mike VP8NO
>
>
> -------- Forwarded Message --------
> Subject: AW: [Elecraft] K3 KPA3 bias adjust
> Date: Sat, 3 Jan 2009 19:46:55 +0100
> From: Koppendorfer Klaus <[hidden email]>
> To: Jan Erik Holm <[hidden email]>
> CC: [hidden email] <[hidden email]>
>
> Locate the BIAS pot at the front of the KPA3, between the heat sink and
> the KPA3 shield. Note what the display current is in the VFO B readout
> when you tap the Display button and turn the VFO B knob to the current
> readout. In RX, it should be 1.0A or so. In XMIT (not TUNE), it should
> be about 1.90 to 2.0A when the Power knob is set to 12w or above so the
> KPA3 is made active (but there is no RF output since XMIT is used). Or
> you can press the PTT button but do not speak.
>
> If there is much more current than this, set the BIAS pot to minimum
> (fully counter clockwise). Then tap XMIT (not TUNE) and note what the
> current is in VFO B's readout. Slowly turn up the BIAS pot until you see
> 400-500mA more current that was seen with the BIAS pot at minimum.
>

ke9uw

Re: Fwd: AW: K3 KPA3 bias adjust

Could you be mistaken on my procedure? The 1 amp plus or minus is typical with three K3s es that I know of. There are two devices and two trim pots.

This instruction is only for one device since he says "the BIAS pot" I believe...

" If there is much more current than this, set the BIAS pot to minimum
(fully counter clockwise). Then tap XMIT (not TUNE) and note what the
current is in VFO B's readout. Slowly turn up the BIAS pot until you see
400-500mA more current that was seen with the BIAS pot at minimum."

I am looking at the total current accessible from DISP and read out on the front panel. First I go to the LPA only, read the total current drawn by the rig under XMIT SSB(no modulation) and then engage the KPA by turning up the power knob and I subtract the first reading from the second. I get about 1.05 amps.
Am I close to knowing the total current into the KPA this way?

I feel that this important knowledge about how to set up the amp is fuzzy or not well known...the why I asked the question.

Thanks for the replies!!

Chuck Hawley
[hidden email]

Amateur Radio, KE9UW
aka Jack, BMW Motorcycles

________________________________
From: Don Wilhelm <[hidden email]>
Sent: Thursday, March 7, 2019 12:10 PM
To: hawley, charles j jr; [hidden email]; Mike Harris
Subject: Re: [Elecraft] Fwd: AW: K3 KPA3 bias adjust

Chuck,

The instruction cited was for a 400-500 ma rise TOTAL (not per device).
So I conclude your bias is set too high or there is a problem in the
bias circuit.

73,
Don W3FPR

On 3/7/2019 9:31 AM, hawley, charles j jr wrote:

Chuck, KE9UW

Don Wilhelm

Re: Fwd: AW: K3 KPA3 bias adjust

Chuck,

True, but make sure that current is being distributed equally between
the 2 devices. Set both pots to full CCW and then adjust one for a
400-500ma rise, then adjust the other for another 400-500ma rise.
You should then have a 1 amp rise total, but you will be assured that
each device is drawing the proper amount of idle current.

73,
Don W3FPR

On 3/7/2019 1:34 PM, hawley, charles j jr wrote:

> Could you be mistaken on my procedure? The 1 amp plus or minus is
> typical with three K3s es that I know of. There are two devices and
> two trim pots.
>
> This instruction is only for one device since he says "the BIAS pot" I
> believe...
>
> "If there is much more current than this, set the BIAS pot to minimum
> (fully counter clockwise). Then tap XMIT (not TUNE) and note what the
> current is in VFO B's readout. Slowly turn up the BIAS pot until you see
> 400-500mA more current that was seen with the BIAS pot at minimum."
>
> I am looking at the total current accessible from DISP and read out on
> the front panel. First I go to the LPA only, read the total current
> drawn by the rig under XMIT SSB(no modulation) and then engage the KPA
> by turning up the power knob and I subtract the first reading from the
> second. I get about 1.05 amps.
> Am I close to knowing the total current into the KPA this way?
>
> I feel that this important knowledge about how to set up the amp is
> fuzzy or not well known...the why I asked the question.
>
> Thanks for the replies!!
>
> Chuck Hawley
> [hidden email]
>
> Amateur Radio, KE9UW
> aka Jack, BMW Motorcycles
>
> ------------------------------------------------------------------------
> *From:* Don Wilhelm <[hidden email]>
> *Sent:* Thursday, March 7, 2019 12:10 PM
> *To:* hawley, charles j jr; [hidden email]; Mike Harris
> *Subject:* Re: [Elecraft] Fwd: AW: K3 KPA3 bias adjust
> Chuck,
>
> The instruction cited was for a 400-500 ma rise TOTAL (not per device).
> So I conclude your bias is set too high or there is a problem in the
> bias circuit.
>
> 73,
> Don W3FPR
>
> On 3/7/2019 9:31 AM, hawley, charles j jr wrote:
> > Thanks for the info. Using xmit for the low power amp and then going
> to the high power amp shows a difference of 1.05A. So my devices are
> showing about 500+ ma each. In the ball park.
> > Thanks so much for the reply.
> >
> > Chuck Hawley
> >   [hidden email]
> >
> >   Amateur Radio, KE9UW
> >   aka Jack, BMW Motorcycles
> >
> > ________________________________
> > From: [hidden email]
> <[hidden email]> on behalf of Mike Harris via
> Elecraft <[hidden email]>
> > Sent: Thursday, March 7, 2019 5:43 AM
> > To: [hidden email]
> > Subject: [Elecraft] Fwd: AW: K3 KPA3 bias adjust
> >
> > Hi,
> >
> > Forwarded a 2009 email exchange for your info. I have NOT tried this so
> > use with care and at your own risk.
> >
> > Regards,
> >
> > Mike VP8NO
> >
> >
> > -------- Forwarded Message --------
> > Subject: AW: [Elecraft] K3 KPA3 bias adjust
> > Date: Sat, 3 Jan 2009 19:46:55 +0100
> > From: Koppendorfer Klaus <[hidden email]>
> > To: Jan Erik Holm <[hidden email]>
> > CC: [hidden email] <[hidden email]>
> >
> > Locate the BIAS pot at the front of the KPA3, between the heat sink and
> > the KPA3 shield. Note what the display current is in the VFO B readout
> > when you tap the Display button and turn the VFO B knob to the current
> > readout. In RX, it should be 1.0A or so.   In XMIT (not TUNE), it should
> > be about 1.90 to 2.0A when the Power knob is set to 12w or above so the
> > KPA3 is made active (but there is no RF output since XMIT is used). Or
> > you can press the PTT button but do not speak.
> >
> > If there is much more current than this, set the BIAS pot to minimum
> > (fully counter clockwise). Then tap XMIT (not TUNE) and note what the
> > current is in VFO B's readout. Slowly turn up the BIAS pot until you see
> > 400-500mA more current that was seen with the BIAS pot at minimum.
> >

Bob McGraw - K4TAX

Re: Fwd: AW: K3 KPA3 bias adjust

In reply to this post by ke9uw

I just looked at the current values of my K3s using the internal DISP
current and voltage values.

This is how it came from the factory after replacement of the KPA3A rev
E amp on 5/30/2018.

In RX USB mode = 1.6A Vcc = 13.8V Audio volume at minimum.

In TX USB mode no audio, 10 watt PWR setting = 1.60A

In TX USB mode no audio, 100 watt PWR setting = 2.91A

The PWR delta is 1.31 amps

In RX CW mode, = 1.03A Vcc 13.8V Audio volume at minimum.

In TX CW mode PTT closed, key open, 10 watt PWR setting 1.54A Vcc 13.7V

In TX XW mode, PTT closed, key open, 100 watt PWR setting 2.85A Vcc 13.6V

The PWR delta is 1.31 amps

Your values may be different if you have the 2nd receiver and can vary
depending on your Vcc.

73

Bob, K4TAX

On 3/7/2019 12:34 PM, hawley, charles j jr wrote:

> Could you be mistaken on my procedure? The 1 amp plus or minus is typical with three K3s es that I know of. There are two devices and two trim pots.
>
> This instruction is only for one device since he says "the BIAS pot" I believe...
>
> " If there is much more current than this, set the BIAS pot to minimum
> (fully counter clockwise). Then tap XMIT (not TUNE) and note what the
> current is in VFO B's readout. Slowly turn up the BIAS pot until you see
> 400-500mA more current that was seen with the BIAS pot at minimum."
>
> I am looking at the total current accessible from DISP and read out on the front panel. First I go to the LPA only, read the total current drawn by the rig under XMIT SSB(no modulation) and then engage the KPA by turning up the power knob and I subtract the first reading from the second. I get about 1.05 amps.
> Am I close to knowing the total current into the KPA this way?
>
> I feel that this important knowledge about how to set up the amp is fuzzy or not well known...the why I asked the question.
>
> Thanks for the replies!!
>
> Chuck Hawley
> [hidden email]
>
> Amateur Radio, KE9UW
> aka Jack, BMW Motorcycles
>
> ________________________________
> From: Don Wilhelm <[hidden email]>
> Sent: Thursday, March 7, 2019 12:10 PM
> To: hawley, charles j jr; [hidden email]; Mike Harris
> Subject: Re: [Elecraft] Fwd: AW: K3 KPA3 bias adjust
>
> Chuck,
>
> The instruction cited was for a 400-500 ma rise TOTAL (not per device).
> So I conclude your bias is set too high or there is a problem in the
> bias circuit.
>
> 73,
> Don W3FPR
>
> On 3/7/2019 9:31 AM, hawley, charles j jr wrote:
>> Thanks for the info. Using xmit for the low power amp and then going to the high power amp shows a difference of 1.05A. So my devices are showing about 500+ ma each. In the ball park.
>> Thanks so much for the reply.
>>
>> Chuck Hawley
>> [hidden email]
>>
>> Amateur Radio, KE9UW
>> aka Jack, BMW Motorcycles
>>
>> ________________________________
>> From: [hidden email] <[hidden email]> on behalf of Mike Harris via Elecraft <[hidden email]>
>> Sent: Thursday, March 7, 2019 5:43 AM
>> To: [hidden email]
>> Subject: [Elecraft] Fwd: AW: K3 KPA3 bias adjust
>>
>> Hi,
>>
>> Forwarded a 2009 email exchange for your info. I have NOT tried this so
>> use with care and at your own risk.
>>
>> Regards,
>>
>> Mike VP8NO
>>
>>
>> -------- Forwarded Message --------
>> Subject: AW: [Elecraft] K3 KPA3 bias adjust
>> Date: Sat, 3 Jan 2009 19:46:55 +0100
>> From: Koppendorfer Klaus <[hidden email]>
>> To: Jan Erik Holm <[hidden email]>
>> CC: [hidden email] <[hidden email]>
>>
>> Locate the BIAS pot at the front of the KPA3, between the heat sink and
>> the KPA3 shield. Note what the display current is in the VFO B readout
>> when you tap the Display button and turn the VFO B knob to the current
>> readout. In RX, it should be 1.0A or so. In XMIT (not TUNE), it should
>> be about 1.90 to 2.0A when the Power knob is set to 12w or above so the
>> KPA3 is made active (but there is no RF output since XMIT is used). Or
>> you can press the PTT button but do not speak.
>>
>> If there is much more current than this, set the BIAS pot to minimum
>> (fully counter clockwise). Then tap XMIT (not TUNE) and note what the
>> current is in VFO B's readout. Slowly turn up the BIAS pot until you see
>> 400-500mA more current that was seen with the BIAS pot at minimum.
>>
> ______________________________________________________________
> 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
>

Bob McGraw - K4TAX

K3 KPA3 bias adjust

Correction on the RX USB mode current. Should be 1.06 and NOT 1.6.
.......... my oops.

73

Bob, K4TAX

On 3/7/2019 1:03 PM, Bob McGraw K4TAX wrote:

> I just looked at the current values of my K3s using the internal DISP
> current and voltage values.
>
> This is how it came from the factory after replacement of the KPA3A
> rev E amp on 5/30/2018.
>
>
> In RX USB mode = 1.6A Vcc = 13.8V Audio volume at minimum.
> <<note correction above>>
>
> In TX USB mode no audio, 10 watt PWR setting = 1.60A Vcc = 13.7 V
>
> In TX USB mode no audio, 100 watt PWR setting = 2.91A Vcc = 13.6 V
>
> The PWR delta is 1.31 amps
>
>
> In RX CW mode, = 1.03A Vcc 13.8V Audio volume at minimum.
>
> In TX CW mode PTT closed, key open, 10 watt PWR setting 1.54A Vcc 13.7V
>
> In TX XW mode, PTT closed, key open, 100 watt PWR setting 2.85A Vcc 13.6V
>
> The PWR delta is 1.31 amps
>
>
> Your values may be different if you have the 2nd receiver and may
> slightly vary depending on your Vcc.
>
> 73
>
> Bob, K4TAX
>

Bob McGraw - K4TAX

K3 KPA3 bias adjust

In reply to this post by Don Wilhelm

When one starts tinkering with the bias not only should they look at
current value but also at the IMD products while using a spectrum
analyzer. One can tweak the values of IMD down by having the correct
value of bias for each device. They will all be slightly different.
Just because the devices have the same device number and production lot
number does not mean the forward conductivity is the same nor will the
IMD be lowest at a given value of current.

My experience is that ~500 to ~600 ma per device is only a starting
point. Perhaps this is why Elecraft does not want the procedure made
available.

There's two kind of folks; Those that know what they are
doing........and those that think they know what they are doing. So
which group are you in?

73

Bob, K4TAX

______________________________________________________________
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ANDY DURBIN

K3 KPA3 bias adjust

In reply to this post by Jan Erik Holm

If there is only one place to measure the current then the bias adjustments surely need to be done sequentially. For the Kenwood TS-590 the procedure is to set all the bias pots to zero then measure the baseline current. Then increase pot 1 until x mA added to baseline, then increase pot 2 until y mA is added to the new current, then increase pot 3 until z mA added to total current. The final current on its own tells you nothing about how the current is divided between the devices in the final amplifier.

Of course the procedure is not worth anything without knowing what each current increment should be and Kenwood changed their mind about the values after first delivery.

73,
Andy k3wyc
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Elecraft mailing list

Re: Fwd: AW: K3 KPA3 bias adjust

In reply to this post by Bob McGraw - K4TAX

This is interesting.

When I measure the current of my early K3 #00345 using the internal
display I see only a small difference when in TX at 10W or 100W power
setting. Both are in the region of 2.25/2.35A TX (1.22A RX) with the
internal measured voltage RX 14.1V TX 14.0V.

Question is does the KPA3 have bypass mode bias control?

No change if in TX test mode, ensuring no output. The bypass relay
operates and the power display scales correctly with change over Hi/Lo
power.

These numbers compare with the PSU current meter.

Anyone else seeing this? Has something gone missing with a firmware upgrade?

Regards,

Mike VP8NO

On 07/03/2019 16:03, Bob McGraw K4TAX wrote:

> I just looked at the current values of my K3s using the internal DISP
> current and voltage values.
>
> This is how it came from the factory after replacement of the KPA3A rev
> E amp on 5/30/2018.
>
>
> In RX USB mode = 1.6A Vcc = 13.8V Audio volume at minimum.
>
> In TX USB mode no audio, 10 watt PWR setting = 1.60A
>
> In TX USB mode no audio, 100 watt PWR setting = 2.91A
>
> The PWR delta is 1.31 amps
>
>
> In RX CW mode, = 1.03A Vcc 13.8V Audio volume at minimum.
>
> In TX CW mode PTT closed, key open, 10 watt PWR setting 1.54A Vcc 13.7V
>
> In TX XW mode, PTT closed, key open, 100 watt PWR setting 2.85A Vcc 13.6V
>
> The PWR delta is 1.31 amps
>
>
> Your values may be different if you have the 2nd receiver and can vary
> depending on your Vcc.
>
> 73
>
> Bob, K4TAX

ke9uw

Re: K3 KPA3 bias adjust

In reply to this post by Bob McGraw - K4TAX

The more answers I get, the more I fit into the first group :)

Chuck KE9UW
[hidden email]

Sent from my iPad

> On Mar 7, 2019, at 1:21 PM, Bob McGraw K4TAX <[hidden email]> wrote:
>
>
> There's two kind of folks; Those that know what they are doing........and those that think they know what they are doing. So which group are you in?
>
> 73
>
> Bob, K4TAX
>
>
>
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>
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Chuck, KE9UW

Nr4c

Re: K3 KPA3 bias adjust

Yeah, I KNOW what I’m doing. I’m leaving my K3(s) alone!

Sent from my iPhone
...nr4c. bill

> On Mar 7, 2019, at 2:56 PM, hawley, charles j jr <[hidden email]> wrote:
>
> The more answers I get, the more I fit into the first group :)
>
> Chuck KE9UW
> [hidden email]
>
> Sent from my iPad
>
>> On Mar 7, 2019, at 1:21 PM, Bob McGraw K4TAX <[hidden email]> wrote:
>>
>>
>> There's two kind of folks; Those that know what they are doing........and those that think they know what they are doing. So which group are you in?
>>
>> 73
>>
>> Bob, K4TAX
>>
>>
>>
>> ______________________________________________________________
>> 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
> ______________________________________________________________
> 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