Date   

Low Power on 40 meters

McClain Richard
 

I have an old K3 which has low power on 30, 40 and 60 meters. See chart below.

Other bands are OK. The TX Gain calibration did not fix it.


The K3 PWR knob was at full clockwise with display showing 110 watts for all data shown in chart.

Measurements were done with old Heath HM-102 analog meter. Not accurate, but relative measurements.

Any suggestions to get 40 meters level up to 100 watts?

 

73,

Dick, KD4S

 

BAND

POWER

After
TX Gain Calibration POWER

160

100

100

80

95

100

60

70

75

40

75

80

30

75

90

20

110

125

17

110

60

15

120

125

12

120

125

10

100

125

 


Re: KPA 1500 ATU Issue

Dan Abell
 

This is an interesting thread from a sociological standpoint more than technological one :)

But an “appliance operator” is saying it’s not my feedline, not my connectors, not my antennas, but when I drive high power the swr appears the change...

Finally has “he” tried running to amp at reduced power and observed the swr?  (If that was already stated I apologize, just too much text :) 

Dan w3dka

On Jul 3, 2020, at 3:21 PM, Jeff Clarke <ku8e@...> wrote:

Some more information :

This amp was purchased new as a factory built unit in August 2019. When we hooked it up back then the ATU in the KPA1500 seemed to lower the SWR of all his antennas when it was inline. Fast forward to this spring when he noticed the amp was only putting out only half power. It was sent to Elecraft for repair and they determined two of the four final transistors had blown. He just got the amp back from them on Thursday when we hooked it back up. My friend is pretty adamant that there aren't any problems with his antennas. He bases this on the fact that he felt he was getting out pretty well and doing good in contests when running low power when is amp was being repaired. If the SWR was high he just used the internal antenna tuner in his TS590SG to lower the SWR.

 At first I too thought maybe there could be a problem with the traps in his TH6 and suggested to him that it just wasn't noticeable when running low power and maybe he should have his antenna guy check this out. He's not buying this from me.  I also noticed that his 80 meter dipole is resonant around 3625 and when he goes to the bottom of 80 meters the amp faults when tuning on the ATU and won't tune out the SWR. The 40 meter dipole which I recently changed a bad connector on was resonant down in the CW band but when hooked to the amp it has a higher SWR. Not sure what's causing that. The pattern I'm noticing  with his KPA1500 is if the SWR is above 2:1 with the ATU off it won't tune out the mismatch when you turn it on. I guess when I go back over to his house again I should take my antenna analyser over and check all the antennas again by bypassing the radio/amp and double check all the connectors. 

He just sent Elecraft an email and they want him to download the KPA1500 configuration file and email it to them which of course he doesn't know how to do. So I'm going have to go do that as well. My friend is a a total appliance operator and very non-technical so it sometimes gets very challenging for me to help him out.

Jeff


Re: KPA 1500 ATU Issue

NS2N_PTA@outlook.com
 

Jeff take your KPA500 and see if it works any better. Wou;d be a check on the 1500s’ ATU, and

Might show any arc faults.

 

Paul NS2N

 

Sent from Mail for Windows 10

 

From: Jeff Clarke
Sent: Friday, July 3, 2020 4:21 PM
To: Elecraft-K3@groups.io
Subject: Re: [Elecraft-K3] KPA 1500 ATU Issue

 

Some more information :

This amp was purchased new as a factory built unit in August 2019. When we hooked it up back then the ATU in the KPA1500 seemed to lower the SWR of all his antennas when it was inline. Fast forward to this spring when he noticed the amp was only putting out only half power. It was sent to Elecraft for repair and they determined two of the four final transistors had blown. He just got the amp back from them on Thursday when we hooked it back up. My friend is pretty adamant that there aren't any problems with his antennas. He bases this on the fact that he felt he was getting out pretty well and doing good in contests when running low power when is amp was being repaired. If the SWR was high he just used the internal antenna tuner in his TS590SG to lower the SWR.

 At first I too thought maybe there could be a problem with the traps in his TH6 and suggested to him that it just wasn't noticeable when running low power and maybe he should have his antenna guy check this out. He's not buying this from me.  I also noticed that his 80 meter dipole is resonant around 3625 and when he goes to the bottom of 80 meters the amp faults when tuning on the ATU and won't tune out the SWR. The 40 meter dipole which I recently changed a bad connector on was resonant down in the CW band but when hooked to the amp it has a higher SWR. Not sure what's causing that. The pattern I'm noticing  with his KPA1500 is if the SWR is above 2:1 with the ATU off it won't tune out the mismatch when you turn it on. I guess when I go back over to his house again I should take my antenna analyser over and check all the antennas again by bypassing the radio/amp and double check all the connectors. 

He just sent Elecraft an email and they want him to download the KPA1500 configuration file and email it to them which of course he doesn't know how to do. So I'm going have to go do that as well. My friend is a a total appliance operator and very non-technical so it sometimes gets very challenging for me to help him out.

Jeff

 


Re: KPA 1500 ATU Issue

Jeff Clarke
 

Some more information :

This amp was purchased new as a factory built unit in August 2019. When we hooked it up back then the ATU in the KPA1500 seemed to lower the SWR of all his antennas when it was inline. Fast forward to this spring when he noticed the amp was only putting out only half power. It was sent to Elecraft for repair and they determined two of the four final transistors had blown. He just got the amp back from them on Thursday when we hooked it back up. My friend is pretty adamant that there aren't any problems with his antennas. He bases this on the fact that he felt he was getting out pretty well and doing good in contests when running low power when is amp was being repaired. If the SWR was high he just used the internal antenna tuner in his TS590SG to lower the SWR.

 At first I too thought maybe there could be a problem with the traps in his TH6 and suggested to him that it just wasn't noticeable when running low power and maybe he should have his antenna guy check this out. He's not buying this from me.  I also noticed that his 80 meter dipole is resonant around 3625 and when he goes to the bottom of 80 meters the amp faults when tuning on the ATU and won't tune out the SWR. The 40 meter dipole which I recently changed a bad connector on was resonant down in the CW band but when hooked to the amp it has a higher SWR. Not sure what's causing that. The pattern I'm noticing  with his KPA1500 is if the SWR is above 2:1 with the ATU off it won't tune out the mismatch when you turn it on. I guess when I go back over to his house again I should take my antenna analyser over and check all the antennas again by bypassing the radio/amp and double check all the connectors. 

He just sent Elecraft an email and they want him to download the KPA1500 configuration file and email it to them which of course he doesn't know how to do. So I'm going have to go do that as well. My friend is a a total appliance operator and very non-technical so it sometimes gets very challenging for me to help him out.

Jeff


Re: QRPWorks K-Board For Sale

Jim - WS6X
 

The K-Board is sold.

Thanks,

Jim – WS6X


QRPWorks K-Board For Sale

Jim - WS6X
 

Thought I’d try here before “going public” to the ham classifieds. I have for sale an essentially unused smart keyboard interface for a K3/K3s:

 

QRP Works - K-Board K3/K3S Package 2. See the particulars here:

 

https://www.qrpworks.com/k-board-store.html

 

This is a very slick package, and works flawlessly! Reason for selling? Laziness! I simply never got it fully integrated into my two - K3 station. Now I’m facing a downsizing move, so need to part company.

This package is currently selling for $199. In addition, my offer also includes a matching wireless mouse with USB dongle. (Photo available for serious inquiries.)

My asking price = $150 plus shipping.

 

Please contact me off list. IMPORTANT: Send me an email with your phone number, and a good time for me to call! I will call you accordingly. See my email address in QRZ. Thanks for looking.

73,

Jim – WS6X

 


WANTED: 2 2.8KHz filters

Lou Laderman W0FK
 

I'm looking for 2 2.8KHz filters to replace the 2.7KHz's in my K3S. In addition to just buying them outright, I can offer a partial trade by throwing in my 2 2.7KHz's plus cash, or swapping some combination of 2 400Hz or 2 250Hz filters. 
  
Please email me directly at lladerman AT earthlink DOT net. 

73, Lou, W0FK 


Re: K3s USB Codec unplugging itself

ve3ki
 

By default, Windows is set to power down USB ports to save power after a certain time of "inactivity". Inactivity is NOT measured by whether the USB port itself is being used; Windows simply looks for recent mouse and keyboard activity, and if there hasn't been any, it shuts off the USB power regardless of what the USB ports are being used for. For instructions on how to disable this default Windows behaviour, see <http://www.dxlabsuite.com/dxlabwiki/PreventUSBPortPowerDown>. Like many other WIndows settings, after a major Windows update you might need to revisit these settings to enusre that Windows hasn't restored them to defaults.

73,
Rich VE3KI


On Fri, Jul 3, 2020 at 01:04 AM, Joe, KO8V wrote:
I occasionally hear my windows system play the USB disconnect/connect sound when nothing has been plugged in or removed.  Using USBDeview, I found it seems the K3s Audio Codec disconnecting and reconnecting at some random times.  I know the codec is powered and visible to the computer when the radio is off.  I was wondering if there was something in the K3s that will recycle the codec on a random basis or for some other reason. It even happens in the middle of the night when I'm asleep.  
--
73
Joe, KO8V


K3s USB Codec unplugging itself

Joe, KO8V
 

I occasionally hear my windows system play the USB disconnect/connect sound when nothing has been plugged in or removed.  Using USBDeview, I found it seems the K3s Audio Codec disconnecting and reconnecting at some random times.  I know the codec is powered and visible to the computer when the radio is off.  I was wondering if there was something in the K3s that will recycle the codec on a random basis or for some other reason. It even happens in the middle of the night when I'm asleep.  
--
73
Joe, KO8V


Re: KPA 1500 ATU Issue

N6RV
 

I do not know if this works with all radio / KPA1500 combinations however with my K3S/KP1500 I do the following.Hopefully it i something as simple as this.

I do not use the ATU in the K3S.

Tune the ATU in each sub-band (CW, SSB, Digi) using the K3S in Tune mode and selecting ATU Tune on the KPA1500.
I believe the amplifier stores and retrieves the ATU settings on different band segments. It reads the transceiver frequency and switches to the correct ATU settings.

Make sure the ATU is in line by depressing and holding the ATU mode button on the KPA1500. If both LEDs (ATU In & ATU Bypass) are lit the amplifier is indicating that the antenna VSWR is low enough and the ATU is automatically switched out.

Maybe your friend is doing this already. If so, then he has a strange issue.


Re: KPA 1500 ATU Issue

Christopher Scibelli
 

What is the SWR with the amp on but in the SSB part of the band?  Does the SWR jump there too, or does it provide a good match?  I don't know if the TH6 uses traps but it could be the amp heating up the traps.  If the SWR is low on 20 SSB with the amp on that rules traps out.

I've had the SWR climb high due to a balun about to go and then the SWR is sky-high once the balun goes.  Once again check the SWR across the whole band with the amp on and amp off. Rule out any traps and the balun before you conclude it's the amp.  An SWR of 2.4 to 1 in the 20 CW section sounds very high. I had a trapped tribander (Cushcraft A3S) and the SWR never got that high on wider bands never mind 20 meters.  Lastly, does the amp have slugs to tune the SWR for each band?  That's my last idea but I've had those slugs in tube amplifiers. I've never had a SS amplifier.

73,

Chris  NU1O


-----Original Message-----
From: Jeff Clarke <ku8e@...>
To: Elecraft-K3 <Elecraft-K3@groups.io>
Sent: Thu, Jul 2, 2020 3:23 pm
Subject: [Elecraft-K3] KPA 1500 ATU Issue

A friend of mine has a KPA1500 that's having strange issues with the ATU. The SWR on his Hygain TH6 tri-bander is kind of high in the CW band because it's tuned for SSB. When he goes down to CW on 20 meters it's maybe a 2.4 :1 SWR. When you switch in the ATU with the amp in the standby position it gets the SWR down to an acceptable level. When you put the amp into the OPER position the SWR jumps up and causes the amp to fault. It also does this also for his 80 meter and 40 meter dipoles when you get away from the resonate frequency on those bands. Same issue with the TH6 on both 15 and 10 meters where it's not near the resonant frequency. This makes the amp pretty much unusable on frequencies where the SWR is around the 2:0 range or a little above that without putting an external antenna tuner is line after the output. He doesn't want to use it this way and risk blowing the final transistors again.

According to the KPA1500 manual  "At lower amplifier outputs up to about 800 W, or when using your driving transceiver “barefoot” at 100 W, the ATU will match loads up to an SWR of 10:1 on 80 through 10 meters and 5:1 on 160 and 6 meters. At 1500 W the tuner will match an SWR of about 3:1" The SWR on his antennas are well below these SWR readings but the ATU doesn't seem to be working as designed?. My friend is pretty frustrated right now because he just got his amp back from Elecraft (after having no amp for 4 months) to repair two final transistors that blew. He's only owned it for about 10 months. He was really looking forward to being HP again since he's not a LP guy. Lucky for him it was still under warranty and was fixed for free. I wasn't so lucky with my KPA500 and it cost me $600 to ship and have it repaired by Elecraft for blown final transistors.  Now he's not sure he wants to own a solid state amplifier that's so picky about SWR (and having to use an external antenna tuner) that he's just thinking about just selling it and going back to a tube amplifier.

Has anyone else had a similar issue with the ATU? I remember when he first bought the amp a little less than a year ago and we hooked it up it didn't act this way.

Jeff KU8E


Re: KPA 1500 ATU Issue

K9MA
 

The first thing that occurs to me is that something is going wrong with the antennas or feedlines at high power. Does the SWR go high in the OPER position at 100 W, or only at higher power?  Does he have another amplifier he can try with those antennas?

Another possibility is that the ATU is actually failing, but that seem unlikely if the SWR goes back down at low power. I've been running my KPA1500 into antennas with over a 2:1 SWR for a couple years with no problems.


73,
Scott K9MA

On 7/2/2020 14:23, Jeff Clarke wrote:
A friend of mine has a KPA1500 that's having strange issues with the ATU. The SWR on his Hygain TH6 tri-bander is kind of high in the CW band because it's tuned for SSB. When he goes down to CW on 20 meters it's maybe a 2.4 :1 SWR. When you switch in the ATU with the amp in the standby position it gets the SWR down to an acceptable level. When you put the amp into the OPER position the SWR jumps up and causes the amp to fault. It also does this also for his 80 meter and 40 meter dipoles when you get away from the resonate frequency on those bands. Same issue with the TH6 on both 15 and 10 meters where it's not near the resonant frequency. This makes the amp pretty much unusable on frequencies where the SWR is around the 2:0 range or a little above that without putting an external antenna tuner is line after the output. He doesn't want to use it this way and risk blowing the final transistors again.

According to the KPA1500 manual  "At lower amplifier outputs up to about 800 W, or when using your driving transceiver “barefoot” at 100 W, the ATU will match loads up to an SWR of 10:1 on 80 through 10 meters and 5:1 on 160 and 6 meters. At 1500 W the tuner will match an SWR of about 3:1" The SWR on his antennas are well below these SWR readings but the ATU doesn't seem to be working as designed?. My friend is pretty frustrated right now because he just got his amp back from Elecraft (after having no amp for 4 months) to repair two final transistors that blew. He's only owned it for about 10 months. He was really looking forward to being HP again since he's not a LP guy. Lucky for him it was still under warranty and was fixed for free. I wasn't so lucky with my KPA500 and it cost me $600 to ship and have it repaired by Elecraft for blown final transistors.  Now he's not sure he wants to own a solid state amplifier that's so picky about SWR (and having to use an external antenna tuner) that he's just thinking about just selling it and going back to a tube amplifier.

Has anyone else had a similar issue with the ATU? I remember when he first bought the amp a little less than a year ago and we hooked it up it didn't act this way.

Jeff KU8E


-- 
Scott  K9MA

k9ma@...


KPA 1500 ATU Issue

Jeff Clarke
 

A friend of mine has a KPA1500 that's having strange issues with the ATU. The SWR on his Hygain TH6 tri-bander is kind of high in the CW band because it's tuned for SSB. When he goes down to CW on 20 meters it's maybe a 2.4 :1 SWR. When you switch in the ATU with the amp in the standby position it gets the SWR down to an acceptable level. When you put the amp into the OPER position the SWR jumps up and causes the amp to fault. It also does this also for his 80 meter and 40 meter dipoles when you get away from the resonate frequency on those bands. Same issue with the TH6 on both 15 and 10 meters where it's not near the resonant frequency. This makes the amp pretty much unusable on frequencies where the SWR is around the 2:0 range or a little above that without putting an external antenna tuner is line after the output. He doesn't want to use it this way and risk blowing the final transistors again.

According to the KPA1500 manual  "At lower amplifier outputs up to about 800 W, or when using your driving transceiver “barefoot” at 100 W, the ATU will match loads up to an SWR of 10:1 on 80 through 10 meters and 5:1 on 160 and 6 meters. At 1500 W the tuner will match an SWR of about 3:1" The SWR on his antennas are well below these SWR readings but the ATU doesn't seem to be working as designed?. My friend is pretty frustrated right now because he just got his amp back from Elecraft (after having no amp for 4 months) to repair two final transistors that blew. He's only owned it for about 10 months. He was really looking forward to being HP again since he's not a LP guy. Lucky for him it was still under warranty and was fixed for free. I wasn't so lucky with my KPA500 and it cost me $600 to ship and have it repaired by Elecraft for blown final transistors.  Now he's not sure he wants to own a solid state amplifier that's so picky about SWR (and having to use an external antenna tuner) that he's just thinking about just selling it and going back to a tube amplifier.

Has anyone else had a similar issue with the ATU? I remember when he first bought the amp a little less than a year ago and we hooked it up it didn't act this way.

Jeff KU8E


Re: REMOTE ON / OFF for K3

Robert W5AJ
 

Excellent
Thanks

The remote on/off of power at 120vac level is next.

73 W5AJ

On Tue, Jun 30, 2020, 2:56 PM David Robinson <g4fre@...> wrote:
I had a similar issue when wishing to power up the K3 at the remote station every time the 12V power supply was switched on. My solution was an 8 pin PIC, see http://g4fre.com/K3_poweron.htm.

Dave
WW2R
 


Re: Nothing on my monitor from the P3.

radio@ebillsharp.com
 

Thank you Klaas. 

Sherm
w8hi



On Jun 30, 2020, at 4:12 PM, . . via groups.io <pa3ggy@...> wrote:

Hi Guys.

Not had these issue with my line up, however had issues with flashing software. (K3 Bricked)
As Engineer having updated software "all my life" and having experience over here with the K3 - P3
I suggest to disconnect all cables *except for power), put serial cable in K3 only...flash required firmware.
once done take cable put in P3 only  ( make certain it is powered though) flash  required firmware.
Make certain K3 seems to operating normally.... if Ok then hook up P3. nothing else, check for improvement.
In case all ok, add additional monitors and whatever you fancy.
In case nothing hels, there is always Elecraft Tech support., they usually give a rapid response.

Just my 2 cents.

Good luck.

....73.....Klaas..........PA3GGY...........


Re: Using M1-M4 buttons DVR and N1MM, SSB, won't repeat...

Neil G
 

That was exactly the fix, Mike...per N1MM support...logger
doesn't know "length" of message...so add 5 sec to recorded
length of message...works fine now...
73,
Neil
AE1P


Re: REMOTE ON / OFF for K3

David Robinson
 

I had a similar issue when wishing to power up the K3 at the remote station every time the 12V power supply was switched on. My solution was an 8 pin PIC, see http://g4fre.com/K3_poweron.htm.

Dave
WW2R
 


Re: Nothing on my monitor from the P3.

. .
 

Hi Guys.

Not had these issue with my line up, however had issues with flashing software. (K3 Bricked)
As Engineer having updated software "all my life" and having experience over here with the K3 - P3
I suggest to disconnect all cables *except for power), put serial cable in K3 only...flash required firmware.
once done take cable put in P3 only  ( make certain it is powered though) flash  required firmware.
Make certain K3 seems to operating normally.... if Ok then hook up P3. nothing else, check for improvement.
In case all ok, add additional monitors and whatever you fancy.
In case nothing hels, there is always Elecraft Tech support., they usually give a rapid response.

Just my 2 cents.

Good luck.

....73.....Klaas..........PA3GGY...........


Re: P3 display flashing on/off.

Nolan - KI5IO
 

Friend of mine in Eastern Oregon Mountains was experiencing what seemed similar.  Tried all sorts of normal trouble-shooting steps with no resolution.

He was running WSJTx and monitoring WSPR.  When that APP was running the flashing was constant.

He finally did a clean removal of WSJTx and downloaded the current version, did the install ... turned on to where he was again monitoring WSPR and "no flashing".

May be a different type of flashing, but thought I would toss it into the mix of this conversation.

---
73 - Nolan K.
KI5IO


Re: P3 display flashing on/off.

W9BIK
 

Thanks Joe.

The thought that the PTT response is a red herring had occurred to me. That's one reason why I am not 100% sure whether its the K3s or the P3. You are correct that I do not have the TXMON option installed. However, when I disconnect the serial cable the flashing stops, or at least it did the few times I tried that. I try running it for a longer period with the serial cable disconnect tonight and see what happens.

Chuck