Date   

Re: Winlink

Joe Subich, W4TV
 

I opened it, it was selected to the K3 sound card,
Bad idea. If the Windows Default Sound Device is "USB Audio CODEC"
(the sound card in the K3S), *ANY* Windows sounds will go to the
K3S - and go "on the air" if the K3S is in transmit (or has VOX
enabled).

Far better to set the default sound device (and default communications
device) to the sound card in your computer and select the K3S sound
card *in the application software*. Any application that does not
allow selecting an application specific sound card is defective and
should be replaced.

Allowing Windows Sounds (including streaming audio, music, etc.) to
reach the transceiver and go "on the air" is a violation of Part 97
for US licensed amateurs.

73,

... Joe, W4TV


On 2020-11-14 6:41 PM, Dave Cole wrote:
Thank you!!!  I keep my Taskbar not showing, so I never even knew that was there!  I opened it, it was selected to the K3 sound card, so I tried it and it works...  I closed it, and it appears to work now, with no changes...  Maybe it just needed to see the sound card once... Anyway, thanks!!!!!
73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist, RFI
ARRL Asst. Director, NW Division, Technical Resources
On 11/14/20 1:08 PM, Lyn Norstad wrote:
Dave -

In the VARA TNC window (the "Dashboard" sitting down on your Taskbar, not the Session window) under Settings, click on Soundcard.  You'll see it.

73
Lyn, W0LEN


-----Original Message-----
From: Elecraft-K3@groups.io [mailto:Elecraft-K3@groups.io] On Behalf Of Dave Cole
Sent: Saturday, November 14, 2020 2:34 PM
To: Elecraft-K3@groups.io
Subject: Re: [Elecraft-K3] Winlink

Hello Brian,

Thank you for the assistance here!!

I am set up that way, and have been as well...  I looked at the TNC
Setup settings for VARA modem, and they look correct to me...  Where is
the VARA Dashboard?  I found something called VARA TNC Setup, but that
does not mention a sound card setup.  I am getting a Sound Card not set
up error now...  So I must be missing the Sound Card Setup...


73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist, RFI
ARRL Asst. Director, NW Division, Technical Resources

On 11/14/20 12:17 PM, Brian K0DTJ wrote:
Dave -
I just installed VARA with Winlink Express and it seems to be working
fine.  Try this:

In Winlink Express, open a "VARA HF WInlink" session.
In the Vara Winlink session - <call sign> window, select Settings/Radio
Setup
Select Radio Model == Elecraft K3
USB Digital
Radio Control Port == COM4 (or whatever) Baud 38400  (do not enable RTS
or DTR)
PTT Port (Optional)
     Serial Port to Use = K3

Then click UPDATE
I think I was having the same problem as you until I did that last part.

Also, you must open the VARA dashboard window and set up ==
Settings/SoundCard.

73,
Brian, K0DTJ


On 11/14/2020 06:16, Dave Cole wrote:
Same here...  All seems to work, save PTT.  ARDOP works, and PTT
functions...

73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Asst. Director, NW Division, Technical Resources


Re: micro USB from the PC to the K3 -- UPDATE

Brian K0DTJ
 

The KIO3B board which is standard in the K3S and an upgrade option for the K3 uses the standard USB-B connector.  I don't believe the KIO3B boards are currently available. 

Brian, K0DTJ

On 11/14/2020 03:02, Jose Salvador wrote:
Is it possible to somehow connect the audio from a micro usb from the PC to the K3?


Re: micro USB from the PC to the K3

Brian K0DTJ
 

You would need to have the KIO3B upgrade with the onboard soundcard and a cable with the appropriate connector on the K3 end. Not sure which USB connector is needed because I don’t have that upgrade. HTH

73,
Brian, K0DTJ

On Nov 14, 2020, at 05:47, Jose Salvador <jsalvador51@...> wrote:

Is it possible to somehow connect the audio from a micro usb from the PC to the K3?


Re: Winlink

Dave (NK7Z)
 

Thank you!!! I keep my Taskbar not showing, so I never even knew that was there! I opened it, it was selected to the K3 sound card, so I tried it and it works... I closed it, and it appears to work now, with no changes... Maybe it just needed to see the sound card once... Anyway, thanks!!!!!

73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist, RFI
ARRL Asst. Director, NW Division, Technical Resources

On 11/14/20 1:08 PM, Lyn Norstad wrote:
Dave -
In the VARA TNC window (the "Dashboard" sitting down on your Taskbar, not the Session window) under Settings, click on Soundcard. You'll see it.
73
Lyn, W0LEN
-----Original Message-----
From: Elecraft-K3@groups.io [mailto:Elecraft-K3@groups.io] On Behalf Of Dave Cole
Sent: Saturday, November 14, 2020 2:34 PM
To: Elecraft-K3@groups.io
Subject: Re: [Elecraft-K3] Winlink
Hello Brian,
Thank you for the assistance here!!
I am set up that way, and have been as well... I looked at the TNC
Setup settings for VARA modem, and they look correct to me... Where is
the VARA Dashboard? I found something called VARA TNC Setup, but that
does not mention a sound card setup. I am getting a Sound Card not set
up error now... So I must be missing the Sound Card Setup...
73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist, RFI
ARRL Asst. Director, NW Division, Technical Resources
On 11/14/20 12:17 PM, Brian K0DTJ wrote:
Dave -
I just installed VARA with Winlink Express and it seems to be working
fine. Try this:

In Winlink Express, open a "VARA HF WInlink" session.
In the Vara Winlink session - <call sign> window, select Settings/Radio
Setup
Select Radio Model == Elecraft K3
USB Digital
Radio Control Port == COM4 (or whatever) Baud 38400 (do not enable RTS
or DTR)
PTT Port (Optional)
Serial Port to Use = K3

Then click UPDATE
I think I was having the same problem as you until I did that last part.

Also, you must open the VARA dashboard window and set up ==
Settings/SoundCard.

73,
Brian, K0DTJ


On 11/14/2020 06:16, Dave Cole wrote:
Same here... All seems to work, save PTT. ARDOP works, and PTT
functions...

73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Asst. Director, NW Division, Technical Resources


Unsubscribe: https://groups.io/g/Elecraft-K3/leave/defanged
[huntinhmb@coastside.net]


Re: Winlink

Lyn Norstad
 

Dave -

In the VARA TNC window (the "Dashboard" sitting down on your Taskbar, not the Session window) under Settings, click on Soundcard. You'll see it.

73
Lyn, W0LEN

-----Original Message-----
From: Elecraft-K3@groups.io [mailto:Elecraft-K3@groups.io] On Behalf Of Dave Cole
Sent: Saturday, November 14, 2020 2:34 PM
To: Elecraft-K3@groups.io
Subject: Re: [Elecraft-K3] Winlink

Hello Brian,

Thank you for the assistance here!!

I am set up that way, and have been as well... I looked at the TNC
Setup settings for VARA modem, and they look correct to me... Where is
the VARA Dashboard? I found something called VARA TNC Setup, but that
does not mention a sound card setup. I am getting a Sound Card not set
up error now... So I must be missing the Sound Card Setup...


73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist, RFI
ARRL Asst. Director, NW Division, Technical Resources

On 11/14/20 12:17 PM, Brian K0DTJ wrote:
Dave -
I just installed VARA with Winlink Express and it seems to be working
fine. Try this:

In Winlink Express, open a "VARA HF WInlink" session.
In the Vara Winlink session - <call sign> window, select Settings/Radio
Setup
Select Radio Model == Elecraft K3
USB Digital
Radio Control Port == COM4 (or whatever) Baud 38400 (do not enable RTS
or DTR)
PTT Port (Optional)
Serial Port to Use = K3

Then click UPDATE
I think I was having the same problem as you until I did that last part.

Also, you must open the VARA dashboard window and set up ==
Settings/SoundCard.

73,
Brian, K0DTJ


On 11/14/2020 06:16, Dave Cole wrote:
Same here... All seems to work, save PTT. ARDOP works, and PTT
functions...

73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Asst. Director, NW Division, Technical Resources


Unsubscribe: https://groups.io/g/Elecraft-K3/leave/defanged
[huntinhmb@coastside.net]


Re: Winlink

Dave (NK7Z)
 

Hello Brian,

Thank you for the assistance here!!

I am set up that way, and have been as well... I looked at the TNC Setup settings for VARA modem, and they look correct to me... Where is the VARA Dashboard? I found something called VARA TNC Setup, but that does not mention a sound card setup. I am getting a Sound Card not set up error now... So I must be missing the Sound Card Setup...


73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist, RFI
ARRL Asst. Director, NW Division, Technical Resources

On 11/14/20 12:17 PM, Brian K0DTJ wrote:
Dave -
I just installed VARA with Winlink Express and it seems to be working fine.  Try this:
In Winlink Express, open a "VARA HF WInlink" session.
In the Vara Winlink session - <call sign> window, select Settings/Radio Setup
Select Radio Model == Elecraft K3
USB Digital
Radio Control Port == COM4 (or whatever) Baud 38400  (do not enable RTS or DTR)
PTT Port (Optional)
   Serial Port to Use = K3
Then click UPDATE
I think I was having the same problem as you until I did that last part.
Also, you must open the VARA dashboard window and set up == Settings/SoundCard.
73,
Brian, K0DTJ
On 11/14/2020 06:16, Dave Cole wrote:
Same here...  All seems to work, save PTT.  ARDOP works, and PTT functions...

73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Asst. Director, NW Division, Technical Resources


Unsubscribe: https://groups.io/g/Elecraft-K3/leave/defanged [huntinhmb@coastside.net]


Re: Winlink

Brian K0DTJ
 

Dave -
I just installed VARA with Winlink Express and it seems to be working fine.  Try this:

In Winlink Express, open a "VARA HF WInlink" session.
In the Vara Winlink session - <call sign> window, select Settings/Radio Setup
Select Radio Model == Elecraft K3
USB Digital
Radio Control Port == COM4 (or whatever) Baud 38400  (do not enable RTS or DTR)
PTT Port (Optional)
   Serial Port to Use = K3

Then click UPDATE
I think I was having the same problem as you until I did that last part.

Also, you must open the VARA dashboard window and set up == Settings/SoundCard.

73,
Brian, K0DTJ

On 11/14/2020 06:16, Dave Cole wrote:
Same here...  All seems to work, save PTT.  ARDOP works, and PTT functions...

73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Asst. Director, NW Division, Technical Resources


Unsubscribe: https://groups.io/g/Elecraft-K3/leave/defanged [huntinhmb@coastside.net]
-=-=-=-=-=-=-=-=-=-=-=-


Re: K3 transverter connector question

Bob McGraw - K4TAX
 

I use my Down East Microwave 144/28 very satisfactorily with my K3S.  It interfaces easily using the connections provided on the back of the radio.  When I select 144 MHz or other frequency on the radio, everything switches to the transverter as it should and the radio displays the frequency.   I did have to enter a transverter offset to correct the error in the DEMI oscillator.  After a nice period of warm-up frequency is accurate and stable enough for almost all modes. 

73
Bob, K4TAX


Re: K3 LowPowerAmp FET biasing.

Ray Maxfield
 

Makes sense’s to me !    Thanks   Ray

 

Sent from Mail for Windows 10

 

From: David G3YYD via groups.io
Sent: Saturday, November 14, 2020 2:36 AM
To: Elecraft-K3@groups.io
Subject: Re: [Elecraft-K3] K3 LowPowerAmp FET biasing.

 

Ray

 

Q2 is being run in class A for best linearity, while Q4&5 are push pull class AB for a trade off in linearity and efficiency. Q2 will have relative to power output a much higher no signal current than Q4 & 5. If anything Q2 should have a higher no signal current then 200mA.

 

With one stage being amplified by the next stage the IMD products add to their voltage sum and not to their power. Two successive stages with the same IMD products will have an output IMD that is 6dB worse than the individual stage IMD.  So that linear amplifier which has an IMD of 30dB is driven by a rig with IMD of 30dB will have a resultant IMD level of -24dB which is not good. To get near the IMD performance from a final PA the preceding amplifications stages overall IMD levels needs to be at least 15dB lower and preferably 20dB lower.

 

73 David G3YYD

 

From: Elecraft-K3@groups.io [mailto:Elecraft-K3@groups.io] On Behalf Of Ray Maxfield
Sent: 14 November 2020 02:12
To: Elecraft-K3@groups.io
Cc: 'Robert'
Subject: Re: [Elecraft-K3] K3 LowPowerAmp FET biasing.

 

All…….. That seems a little strange to me, as….

Q2 is a 6 Watt part and the Bias (R18) is Set to the same Value as the 15 Watt Parts (Q4-5) !

I would lower it to 100 Ma.    Just my 2 Cents worth.

Ray WA6VAB  K3 # 3824

 

HATE Windows 10

 

From: Chet, N8RA
Sent: Friday, November 13, 2020 9:03 AM
To: Elecraft-K3@groups.io
Cc: 'Robert'
Subject: [Elecraft-K3] K3 LowPowerAmp FET biasing.

 

For others interested in knowing more about this adjustment:

The info I received from Keith WE6R was:

 

"We bias each device at 200ma increase, total for all 3 is 600ma (from fully Counter Clock Wise, CCW). (Tap TX only to turn on Bias, NOT full transmit).

NOTE  there were a *FEW* of the older LPA boards that have the 3 WHITE pots where they were REVERSED action, IE you start fully clockwise equals no current (vs CCW).

 

FYI, there is a NEW formulation of the Q4&5 finals from the manufacturer that requires a resistor change for proper biasing.

We still have some of the correct, older, parts; Elecraft # E580047.

RFParts.com has both, so be careful to get the correct one if you order from there.

Keith WE6R"

 

And on the QTH.com forum this was posted last night:

 

"Tom,

The procedure below is what I received from Elecraft Tech support back in July of 2019.  It worked for me after changing the LPA FETs in my K3.

73,

Scott AD5HS

 

=======================================================

 

You'll need this sequence for setting bias after the fix:

 

*Here is the procedure to check if your LPA module has been adjusted properly for bias current:*

 

(current increases approx. 600 ma when XMIT is tapped (below 12W).

 

1. Remove the 100 watt amplifier (if installed) by disconnecting the fan panel and their 2 connector wires, and the 2 wires to the circuit breaker.  Use care to not pull on the KPA3 too hard and thus let it fly off the connectors and cause damage to it or to the chassis. Use gentle but firm finger pressure, or pry carefully with a plastic tool (such as the K2 green plastic alignment tool), near the two PCB connectors. This will usually help the KPA3 start to move.

 

2. Locate small SMD pots R18, R19 and R24 near the center of the LPA board.  Turn the pots to minimum. (White pots fully CW, Black pots fully

CCW)

 

3. Turn the power knob down to ZERO.

 

4. Tap DISP, (display button), use VFO B to display the current drawn by the radio. For more accurate results, insert a DMM in the positive power supply lead that is set to a current range that can handle up to 2-3 amps.

 

5. Hold TEST (the right hand side of the MODE button). This puts the K3 in TEST mode with no RF drive.

 

6.  Tap XMIT. You will see a current of approx  1 to 2A (depending on options in radio) but the red TX LED will not come on.  Adjust R18 to increase the reading by 0.2A  IE 200ma

 

7. Adjust R19 to increase the current another 0.2A

 

8. Adjust R24 to increase the current another 0.2A

 

9. Tap XMIT to exit bias on condition. (Current should drop approx.

600ma).  NOTE: if you are just checking current and you do have the KPA3 installed, set it to NOT INST and cycle power so you do not have its current added, thus confusing your readings.

 

10. Set Power to 11.9W. Hold TEST again to cancel TEST mode so RF output is possible. The LCD shows TX NORM.

 

11. With PWR SET to “nor” Hold TUNE and see how much power you get on all bands.

 

Elecraft Customer Support

support@...

831-763-4211"

 

 

73,

Chet, N8RA

 

 


Re: Winlink

Dave (NK7Z)
 

Same here... All seems to work, save PTT. ARDOP works, and PTT functions...

73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist, RFI
ARRL Asst. Director, NW Division, Technical Resources

On 11/13/20 9:39 PM, Michael J. Hauan wrote:
Same problem.  Updated Win10 and new install of winlink.  Neither Winmor nor VARA assert PTT while frequency/channel changing works ok.  I've ensured that microphone privacy is set to allow app access.  No joy.
mjh (AC0G)


micro USB from the PC to the K3

Jose Salvador
 

Is it possible to somehow connect the audio from a micro usb from the PC to the K3?


Re: Winlink

Michael J. Hauan
 

Same problem.  Updated Win10 and new install of winlink.  Neither Winmor nor VARA assert PTT while frequency/channel changing works ok.  I've ensured that microphone privacy is set to allow app access.  No joy.

mjh (AC0G)


Re: K3 LowPowerAmp FET biasing.

David G3YYD
 

Ray

 

Q2 is being run in class A for best linearity, while Q4&5 are push pull class AB for a trade off in linearity and efficiency. Q2 will have relative to power output a much higher no signal current than Q4 & 5. If anything Q2 should have a higher no signal current then 200mA.

 

With one stage being amplified by the next stage the IMD products add to their voltage sum and not to their power. Two successive stages with the same IMD products will have an output IMD that is 6dB worse than the individual stage IMD.  So that linear amplifier which has an IMD of 30dB is driven by a rig with IMD of 30dB will have a resultant IMD level of -24dB which is not good. To get near the IMD performance from a final PA the preceding amplifications stages overall IMD levels needs to be at least 15dB lower and preferably 20dB lower.

 

73 David G3YYD

 

From: Elecraft-K3@groups.io [mailto:Elecraft-K3@groups.io] On Behalf Of Ray Maxfield
Sent: 14 November 2020 02:12
To: Elecraft-K3@groups.io
Cc: 'Robert'
Subject: Re: [Elecraft-K3] K3 LowPowerAmp FET biasing.

 

All…….. That seems a little strange to me, as….

Q2 is a 6 Watt part and the Bias (R18) is Set to the same Value as the 15 Watt Parts (Q4-5) !

I would lower it to 100 Ma.    Just my 2 Cents worth.

Ray WA6VAB  K3 # 3824

 

HATE Windows 10

 

From: Chet, N8RA
Sent: Friday, November 13, 2020 9:03 AM
To: Elecraft-K3@groups.io
Cc: 'Robert'
Subject: [Elecraft-K3] K3 LowPowerAmp FET biasing.

 

For others interested in knowing more about this adjustment:

The info I received from Keith WE6R was:

 

"We bias each device at 200ma increase, total for all 3 is 600ma (from fully Counter Clock Wise, CCW). (Tap TX only to turn on Bias, NOT full transmit).

NOTE  there were a *FEW* of the older LPA boards that have the 3 WHITE pots where they were REVERSED action, IE you start fully clockwise equals no current (vs CCW).

 

FYI, there is a NEW formulation of the Q4&5 finals from the manufacturer that requires a resistor change for proper biasing.

We still have some of the correct, older, parts; Elecraft # E580047.

RFParts.com has both, so be careful to get the correct one if you order from there.

Keith WE6R"

 

And on the QTH.com forum this was posted last night:

 

"Tom,

The procedure below is what I received from Elecraft Tech support back in July of 2019.  It worked for me after changing the LPA FETs in my K3.

73,

Scott AD5HS

 

=======================================================

 

You'll need this sequence for setting bias after the fix:

 

*Here is the procedure to check if your LPA module has been adjusted properly for bias current:*

 

(current increases approx. 600 ma when XMIT is tapped (below 12W).

 

1. Remove the 100 watt amplifier (if installed) by disconnecting the fan panel and their 2 connector wires, and the 2 wires to the circuit breaker.  Use care to not pull on the KPA3 too hard and thus let it fly off the connectors and cause damage to it or to the chassis. Use gentle but firm finger pressure, or pry carefully with a plastic tool (such as the K2 green plastic alignment tool), near the two PCB connectors. This will usually help the KPA3 start to move.

 

2. Locate small SMD pots R18, R19 and R24 near the center of the LPA board.  Turn the pots to minimum. (White pots fully CW, Black pots fully

CCW)

 

3. Turn the power knob down to ZERO.

 

4. Tap DISP, (display button), use VFO B to display the current drawn by the radio. For more accurate results, insert a DMM in the positive power supply lead that is set to a current range that can handle up to 2-3 amps.

 

5. Hold TEST (the right hand side of the MODE button). This puts the K3 in TEST mode with no RF drive.

 

6.  Tap XMIT. You will see a current of approx  1 to 2A (depending on options in radio) but the red TX LED will not come on.  Adjust R18 to increase the reading by 0.2A  IE 200ma

 

7. Adjust R19 to increase the current another 0.2A

 

8. Adjust R24 to increase the current another 0.2A

 

9. Tap XMIT to exit bias on condition. (Current should drop approx.

600ma).  NOTE: if you are just checking current and you do have the KPA3 installed, set it to NOT INST and cycle power so you do not have its current added, thus confusing your readings.

 

10. Set Power to 11.9W. Hold TEST again to cancel TEST mode so RF output is possible. The LCD shows TX NORM.

 

11. With PWR SET to “nor” Hold TUNE and see how much power you get on all bands.

 

Elecraft Customer Support

support@...

831-763-4211"

 

 

73,

Chet, N8RA

 


Re: K3 LowPowerAmp FET biasing.

Ray Maxfield
 

All…….. That seems a little strange to me, as….

Q2 is a 6 Watt part and the Bias (R18) is Set to the same Value as the 15 Watt Parts (Q4-5) !

I would lower it to 100 Ma.    Just my 2 Cents worth.

Ray WA6VAB  K3 # 3824

 

HATE Windows 10

 

From: Chet, N8RA
Sent: Friday, November 13, 2020 9:03 AM
To: Elecraft-K3@groups.io
Cc: 'Robert'
Subject: [Elecraft-K3] K3 LowPowerAmp FET biasing.

 

For others interested in knowing more about this adjustment:

The info I received from Keith WE6R was:

 

"We bias each device at 200ma increase, total for all 3 is 600ma (from fully Counter Clock Wise, CCW). (Tap TX only to turn on Bias, NOT full transmit).

NOTE  there were a *FEW* of the older LPA boards that have the 3 WHITE pots where they were REVERSED action, IE you start fully clockwise equals no current (vs CCW).

 

FYI, there is a NEW formulation of the Q4&5 finals from the manufacturer that requires a resistor change for proper biasing.

We still have some of the correct, older, parts; Elecraft # E580047.

RFParts.com has both, so be careful to get the correct one if you order from there.

Keith WE6R"

 

And on the QTH.com forum this was posted last night:

 

"Tom,

The procedure below is what I received from Elecraft Tech support back in July of 2019.  It worked for me after changing the LPA FETs in my K3.

73,

Scott AD5HS

 

=======================================================

 

You'll need this sequence for setting bias after the fix:

 

*Here is the procedure to check if your LPA module has been adjusted properly for bias current:*

 

(current increases approx. 600 ma when XMIT is tapped (below 12W).

 

1. Remove the 100 watt amplifier (if installed) by disconnecting the fan panel and their 2 connector wires, and the 2 wires to the circuit breaker.  Use care to not pull on the KPA3 too hard and thus let it fly off the connectors and cause damage to it or to the chassis. Use gentle but firm finger pressure, or pry carefully with a plastic tool (such as the K2 green plastic alignment tool), near the two PCB connectors. This will usually help the KPA3 start to move.

 

2. Locate small SMD pots R18, R19 and R24 near the center of the LPA board.  Turn the pots to minimum. (White pots fully CW, Black pots fully

CCW)

 

3. Turn the power knob down to ZERO.

 

4. Tap DISP, (display button), use VFO B to display the current drawn by the radio. For more accurate results, insert a DMM in the positive power supply lead that is set to a current range that can handle up to 2-3 amps.

 

5. Hold TEST (the right hand side of the MODE button). This puts the K3 in TEST mode with no RF drive.

 

6.  Tap XMIT. You will see a current of approx  1 to 2A (depending on options in radio) but the red TX LED will not come on.  Adjust R18 to increase the reading by 0.2A  IE 200ma

 

7. Adjust R19 to increase the current another 0.2A

 

8. Adjust R24 to increase the current another 0.2A

 

9. Tap XMIT to exit bias on condition. (Current should drop approx.

600ma).  NOTE: if you are just checking current and you do have the KPA3 installed, set it to NOT INST and cycle power so you do not have its current added, thus confusing your readings.

 

10. Set Power to 11.9W. Hold TEST again to cancel TEST mode so RF output is possible. The LCD shows TX NORM.

 

11. With PWR SET to “nor” Hold TUNE and see how much power you get on all bands.

 

Elecraft Customer Support

support@...

831-763-4211"

 

 

73,

Chet, N8RA

 


Re: K3 repairs

Barney Scholl
 

Chet, I have been following this thread and I will be anxious to see the final result. I noticed the behavior in my K3. But it seemed very intermittent. Mine passed the calibration test. I have not done the driver test yet since the last time I checked on 40 it was working. It was strange that it only on 40. I have been generally running my KPA500 so it might show up all the time.

73 Barney K3LA.


FW: K3 LowPowerAmp FET biasing.

Chet, N8RA
 

Let me try this again, good at EE but bad at formatting.

N8RA

 

From: Chet S <chetsubaccount@...>
Sent: Friday, November 13, 2020 12:03 PM
To: 'Elecraft-K3@groups.io' <Elecraft-K3@groups.io>
Cc: 'Robert' <woodr90@...>
Subject: K3 LowPowerAmp FET biasing.

 

For others interested in knowing more about this adjustment:

The info I received from Keith WE6R was:

 

"We bias each device at 200ma increase, total for all 3 is 600ma (from fully Counter Clock Wise, CCW). (Tap TX only to turn on Bias, NOT full transmit).

NOTE  there were a *FEW* of the older LPA boards that have the 3 WHITE pots where they were REVERSED action, IE you start fully clockwise equals no current (vs CCW).

 

FYI, there is a NEW formulation of the Q4&5 finals from the manufacturer that requires a resistor change for proper biasing.

We still have some of the correct, older, parts; Elecraft # E580047.

RFParts.com has both, so be careful to get the correct one if you order from there.

Keith WE6R"

 

And on the QTH.com forum this was posted last night:

 

"Tom,

The procedure below is what I received from Elecraft Tech support back in July of 2019.  It worked for me after changing the LPA FETs in my K3.

73,

Scott AD5HS

 

=======================================================

 

You'll need this sequence for setting bias after the fix:

 

*Here is the procedure to check if your LPA module has been adjusted properly for bias current:*

 

(current increases approx. 600 ma when XMIT is tapped (below 12W).

 

1. Remove the 100 watt amplifier (if installed) by disconnecting the fan panel and their 2 connector wires, and the 2 wires to the circuit breaker.  Use care to not pull on the KPA3 too hard and thus let it fly off the connectors and cause damage to it or to the chassis. Use gentle but firm finger pressure, or pry carefully with a plastic tool (such as the K2 green plastic alignment tool), near the two PCB connectors. This will usually help the KPA3 start to move.

 

2. Locate small SMD pots R18, R19 and R24 near the center of the LPA board.  Turn the pots to minimum. (White pots fully CW, Black pots fully

CCW)

 

3. Turn the power knob down to ZERO.

 

4. Tap DISP, (display button), use VFO B to display the current drawn by the radio. For more accurate results, insert a DMM in the positive power supply lead that is set to a current range that can handle up to 2-3 amps.

 

5. Hold TEST (the right hand side of the MODE button). This puts the K3 in TEST mode with no RF drive.

 

6.  Tap XMIT. You will see a current of approx  1 to 2A (depending on options in radio) but the red TX LED will not come on.  Adjust R18 to increase the reading by 0.2A  IE 200ma

 

7. Adjust R19 to increase the current another 0.2A

 

8. Adjust R24 to increase the current another 0.2A

 

9. Tap XMIT to exit bias on condition. (Current should drop approx.

600ma).  NOTE: if you are just checking current and you do have the KPA3 installed, set it to NOT INST and cycle power so you do not have its current added, thus confusing your readings.

 

10. Set Power to 11.9W. Hold TEST again to cancel TEST mode so RF output is possible. The LCD shows TX NORM.

 

11. With PWR SET to “nor” Hold TUNE and see how much power you get on all bands.

 

Elecraft Customer Support

support@...

831-763-4211"

 

 

73,

Chet, N8RA


K3 LowPowerAmp FET biasing.

Chet, N8RA
 

For others interested in knowing more about this adjustment:

The info I received from Keith WE6R was:

 

"We bias each device at 200ma increase, total for all 3 is 600ma (from fully Counter Clock Wise, CCW). (Tap TX only to turn on Bias, NOT full transmit).

NOTE  there were a *FEW* of the older LPA boards that have the 3 WHITE pots where they were REVERSED action, IE you start fully clockwise equals no current (vs CCW).

 

FYI, there is a NEW formulation of the Q4&5 finals from the manufacturer that requires a resistor change for proper biasing.

We still have some of the correct, older, parts; Elecraft # E580047.

RFParts.com has both, so be careful to get the correct one if you order from there.

Keith WE6R"

 

And on the QTH.com forum this was posted last night:

 

"Tom,

The procedure below is what I received from Elecraft Tech support back in July of 2019.  It worked for me after changing the LPA FETs in my K3.

73,

Scott AD5HS

 

=======================================================

 

You'll need this sequence for setting bias after the fix:

 

*Here is the procedure to check if your LPA module has been adjusted properly for bias current:*

 

(current increases approx. 600 ma when XMIT is tapped (below 12W).

 

1. Remove the 100 watt amplifier (if installed) by disconnecting the fan panel and their 2 connector wires, and the 2 wires to the circuit breaker.  Use care to not pull on the KPA3 too hard and thus let it fly off the connectors and cause damage to it or to the chassis. Use gentle but firm finger pressure, or pry carefully with a plastic tool (such as the K2 green plastic alignment tool), near the two PCB connectors. This will usually help the KPA3 start to move.

 

2. Locate small SMD pots R18, R19 and R24 near the center of the LPA board.  Turn the pots to minimum. (White pots fully CW, Black pots fully

CCW)

 

3. Turn the power knob down to ZERO.

 

4. Tap DISP, (display button), use VFO B to display the current drawn by the radio. For more accurate results, insert a DMM in the positive power supply lead that is set to a current range that can handle up to 2-3 amps.

 

5. Hold TEST (the right hand side of the MODE button). This puts the K3 in TEST mode with no RF drive.

 

6.  Tap XMIT. You will see a current of approx  1 to 2A (depending on options in radio) but the red TX LED will not come on.  Adjust R18 to increase the reading by 0.2A  IE 200ma

 

7. Adjust R19 to increase the current another 0.2A

 

8. Adjust R24 to increase the current another 0.2A

 

9. Tap XMIT to exit bias on condition. (Current should drop approx.

600ma).  NOTE: if you are just checking current and you do have the KPA3 installed, set it to NOT INST and cycle power so you do not have its current added, thus confusing your readings.

 

10. Set Power to 11.9W. Hold TEST again to cancel TEST mode so RF output is possible. The LCD shows TX NORM.

 

11. With PWR SET to “nor” Hold TUNE and see how much power you get on all bands.

 

Elecraft Customer Support

support@...

831-763-4211"

 

 

73,

Chet, N8RA


Re: Spare part info

Drew Vonada-Smith K3PA
 

Thats not true.  Buy the part from Elecraft.


Re: K3 transverter connector question

Chris Cox, N0UK
 

Good morning, Colin.

I wasn’t aware of that. I thought that I got to enter both the I/F and the equivalent R/F frequencies when defining a transverter configuration. I don’t have the internal Elecraft transverter. I was going to interface the rig with my old DownEast Microwave 144 to 28 MHz transverter.

73!
Chris Cox, N0UK
chrisc@chris.org

On Nov 12, 2020, at 7:03 PM, Colin Smithers <colin@crsmithers.com> wrote:

On problem you will need to solve is that the Transvertor IF offset values are fixed, so the reading will be 2MHz off( as I understand it).

73, Colin G4CWH
On 12 Nov 2020, at 22:08, Chris Cox, N0UK via groups.io <chrisc=chris.org@groups.io> wrote:

Good day.

I am considering recrystalling my 2m transverter with a 118MHz rock replacing the existing 116MHz crystal, thereby permitting full two metre band coverage with a 26-30MHz I/F.

Does the K3 need to be widebanded to enable low-level 26-28MHz RF on the transverter transmit port or is the low-level output available by default?

--
Chris Cox, N0UK, G4JEC
chrisc@chris.org









Spare part info

Tim Hague M0AFJ <m0afj@...>
 

Hi, I need to change the Power pot on the front panel, does anyone know where these are available if Elecraft are no longer supporting the K3?

thanks
Tim M0AFJ

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