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[K2] Update: K2/100 loss of power control (long post)

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aj4tf

[K2] Update: K2/100 loss of power control (long post)

K2/100 s/n 7006
Initial symptom: No control of output power at any knob setting. At
1-9W setting, output was >10W as measured by external wattmeter, SWR
read back >9.9 (external meter shows around 1:1). At 10-100W setting,
output >100W, SWR >9.9. HI REFL message displayed.

Unit was previously working fine for several months.

Troubleshooting procedure I used:

1) Disassembled KPA100 from radio (but still connected).
Repeated test using 50 ohm dummy load, same results.
SWR reading >9.9

2) Set to 40M, 7200 kHz, set power to 5W, and made the following KPA100
measurements during TUNE cycle:
U5-5: 0.2V (VFWD)
U5-7: 0.2V
U5-3: 2.01V (VREF)
U5-1: 2.01V

So, I assume the microcontroller is seeing this and measuring a high
SWR. HI REFL message was displayed.

3) Using diode check function on Fluke 8021B, measured D16 and D17 in
circuit, each showed approx. 0.4 V forward bias, and open reversed.
However I am not yet convinced that the diodes are not damaged in some
way (see below).

4) I went through the SWR Bridge Null adjustment procedure in the KPA100
manual. However, I was unable to get a measurement of 43 kohms on the
wiper on R26 to ground, I was only able to get a maximum of 30 kohms,
and with the wiper centered, it read about 23 k ohms. I left both R26
and R27 centered.

5) At 5W power, I was able to adjust C1 to obtain a 1.0 SWR reading,
noting that C1 appeared to be in almost the same position as before.

6) Set to 40M, 7200 kHz, set power to 5W, and made the following KPA100
measurements during TUNE cycle. Indicated power 6.0W, indicated 1.0
SWR reading from display. In each case, I allowed about 5 seconds for
the output to stabilize before taking each measurement.
U5-5: 1.4V
U5-7: 1.4V
U5-3: 0.02V
U5-1: 0.02V
U6-6: 2.8V
U6-3: 1.4V
At this point I am reasonably certain that U5 and U6 are working.

7) set power to 15W, (heard relay switch to KPA100) and made the
following KPA100 measurements during TUNE cycle. Indicated power 15W,
indicated 1.2 SWR reading from display, external wattmeter showed >20W
and 1:1 SWR.
U5-5: 2.25V
U5-7: 2.25V
U5-3: 0.3V
U5-1: 0.3V
U6-6: 1.41V
U6-3: 0.71V

8) set power to 20W, and made the following KPA100 measurements during
TUNE cycle. Indicated power 20W, indicated 1.6 SWR reading from
display, external wattmeter showed ~40W and 1:1 SWR.
U5-7: 2.55V
U5-3: 0.6V
U5-1: 0.6V
U6-6: 1.62V
U6-3: 0.81Vmeter showed >40W and 1:1 SWR.
U5-5: 2.55V
U5-7: 2.55V
U5-3: 0.6V
U5-1: 0.6V
U6-6: 1.62V
U6-3: 0.81V

9) set power to 40W, at this point, I was able to re-adjust R26/R27 to
match the externally measured output power to the indicated power
(within a few watts, and limited by the accuracy of the external power
meter).
After adjusting R26/R27: Indicated power 42W, indicated 1.8 SWR
reading from display, external wattmeter showed ~40W and 1:1 SWR.
U5-5: 3.76V
U5-7: 3.76V
U5-3: 1.15V
U5-1: 1.15V
U6-6: 2.37V
U6-3: 1.18V

10) set power to 60W, Indicated power 60W, indicated 2.3 SWR reading
from display, external wattmeter showed ~60W and 1:1 SWR.
U5-5: 4.4V
U5-7: 4.4V
U5-3: 1.72V
U5-1: 1.72V
U6-6: 2.78V
U6-3: 1.39V

So, after all of this, my conclusion is that D16 and D17 may be leaky,
or somehow defective, and providing invalid voltages to the measuring
circuit. I do not believe that U5 or U6 are defective, and it appears
that the microcontroller is controlling the power based on the voltages
it is seeing.

I would appreciate any other opinions or insight, or any other
suggestions on what else to check. In the meantime I'll go ahead and
order some replacement 1N5711's. Static electricity? Lightning?

David AJ4TF

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Don Wilhelm-4

Re: [K2] Update: K2/100 loss of power control (long post)

David,

Yes, it looks like U5, U6, Q10, Q11 and the associated components are
behaving as they should.

It certainly could be that D16 and D17 are not either open or shorted,
but are not fully functioning as they should. The fact that you could
only get the resistance measured at the wiper of R26 as high as 30k does
confirm that -- replace the diodes.

It also seems from your description that things are a bit intermittent
and erratic, so while you are in there to replace the diodes, give the
soldering in the wattmeter area (particularly T4) a good inspection and
perhaps re-flow the solder with a hot iron (800 degF for the KPA100
board), and perhaps add a tiny bit of new solder (actually you are
adding a bit of flux).

Yes, those diodes are sensitive to lightning surges. Switch the K2
antenna to a dummy load when not in use for best results.

73,
Don W3FPR

On 6/11/2011 4:42 PM, david wrote:

> K2/100 s/n 7006
> Initial symptom: No control of output power at any knob setting. At
> 1-9W setting, output was>10W as measured by external wattmeter, SWR
> read back>9.9 (external meter shows around 1:1). At 10-100W setting,
> output>100W, SWR>9.9. HI REFL message displayed.
>
> Unit was previously working fine for several months.
>
> Troubleshooting procedure I used:
>
> 1) Disassembled KPA100 from radio (but still connected).
> Repeated test using 50 ohm dummy load, same results.
> SWR reading>9.9
>
> 2) Set to 40M, 7200 kHz, set power to 5W, and made the following KPA100
> measurements during TUNE cycle:
> U5-5: 0.2V (VFWD)
> U5-7: 0.2V
> U5-3: 2.01V (VREF)
> U5-1: 2.01V
>
> So, I assume the microcontroller is seeing this and measuring a high
> SWR. HI REFL message was displayed.
>
> 3) Using diode check function on Fluke 8021B, measured D16 and D17 in
> circuit, each showed approx. 0.4 V forward bias, and open reversed.
> However I am not yet convinced that the diodes are not damaged in some
> way (see below).
>
> 4) I went through the SWR Bridge Null adjustment procedure in the KPA100
> manual. However, I was unable to get a measurement of 43 kohms on the
> wiper on R26 to ground, I was only able to get a maximum of 30 kohms,
> and with the wiper centered, it read about 23 k ohms. I left both R26
> and R27 centered.
>
> 5) At 5W power, I was able to adjust C1 to obtain a 1.0 SWR reading,
> noting that C1 appeared to be in almost the same position as before.
>
> 6) Set to 40M, 7200 kHz, set power to 5W, and made the following KPA100
> measurements during TUNE cycle. Indicated power 6.0W, indicated 1.0
> SWR reading from display. In each case, I allowed about 5 seconds for
> the output to stabilize before taking each measurement.
> U5-5: 1.4V
> U5-7: 1.4V
> U5-3: 0.02V
> U5-1: 0.02V
> U6-6: 2.8V
> U6-3: 1.4V
> At this point I am reasonably certain that U5 and U6 are working.
>
> 7) set power to 15W, (heard relay switch to KPA100) and made the
> following KPA100 measurements during TUNE cycle. Indicated power 15W,
> indicated 1.2 SWR reading from display, external wattmeter showed>20W
> and 1:1 SWR.
> U5-5: 2.25V
> U5-7: 2.25V
> U5-3: 0.3V
> U5-1: 0.3V
> U6-6: 1.41V
> U6-3: 0.71V
>
> 8) set power to 20W, and made the following KPA100 measurements during
> TUNE cycle. Indicated power 20W, indicated 1.6 SWR reading from
> display, external wattmeter showed ~40W and 1:1 SWR.
> U5-7: 2.55V
> U5-3: 0.6V
> U5-1: 0.6V
> U6-6: 1.62V
> U6-3: 0.81Vmeter showed>40W and 1:1 SWR.
> U5-5: 2.55V
> U5-7: 2.55V
> U5-3: 0.6V
> U5-1: 0.6V
> U6-6: 1.62V
> U6-3: 0.81V
>
> 9) set power to 40W, at this point, I was able to re-adjust R26/R27 to
> match the externally measured output power to the indicated power
> (within a few watts, and limited by the accuracy of the external power
> meter).
> After adjusting R26/R27: Indicated power 42W, indicated 1.8 SWR
> reading from display, external wattmeter showed ~40W and 1:1 SWR.
> U5-5: 3.76V
> U5-7: 3.76V
> U5-3: 1.15V
> U5-1: 1.15V
> U6-6: 2.37V
> U6-3: 1.18V
>
> 10) set power to 60W, Indicated power 60W, indicated 2.3 SWR reading
> from display, external wattmeter showed ~60W and 1:1 SWR.
> U5-5: 4.4V
> U5-7: 4.4V
> U5-3: 1.72V
> U5-1: 1.72V
> U6-6: 2.78V
> U6-3: 1.39V
>
> So, after all of this, my conclusion is that D16 and D17 may be leaky,
> or somehow defective, and providing invalid voltages to the measuring
> circuit. I do not believe that U5 or U6 are defective, and it appears
> that the microcontroller is controlling the power based on the voltages
> it is seeing.
>
> I would appreciate any other opinions or insight, or any other
> suggestions on what else to check. In the meantime I'll go ahead and
> order some replacement 1N5711's. Static electricity? Lightning?
>
> David AJ4TF
>
>
> ______________________________________________________________
> 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
>

______________________________________________________________
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Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

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Please help support this email list: http://www.qsl.net/donate.html

aj4tf

Re: [K2] Update: K2/100 loss of power control (long post)

Don,

Thanks for confirming my diagnosis. I *usually* remember to disconnect
the antenna when I am not operating.

I assume that the standard 1N5711 will work, Elecraft doesn't screen
them for any special characteristics do they?

As always, I'm sure I not the only one that appreciates the knowledge
you bring to the Elecraft community.

David AJ4TF

On Sat, 2011-06-11 at 18:13 -0400, Don Wilhelm wrote:

> David,
>
> Yes, it looks like U5, U6, Q10, Q11 and the associated components are
> behaving as they should.
>
> It certainly could be that D16 and D17 are not either open or shorted,
> but are not fully functioning as they should. The fact that you could
> only get the resistance measured at the wiper of R26 as high as 30k does
> confirm that -- replace the diodes.
>
> It also seems from your description that things are a bit intermittent
> and erratic, so while you are in there to replace the diodes, give the
> soldering in the wattmeter area (particularly T4) a good inspection and
> perhaps re-flow the solder with a hot iron (800 degF for the KPA100
> board), and perhaps add a tiny bit of new solder (actually you are
> adding a bit of flux).
>
> Yes, those diodes are sensitive to lightning surges. Switch the K2
> antenna to a dummy load when not in use for best results.
>
> 73,
> Don W3FPR
>
> On 6/11/2011 4:42 PM, david wrote:
> > K2/100 s/n 7006
> > Initial symptom: No control of output power at any knob setting. At
> > 1-9W setting, output was>10W as measured by external wattmeter, SWR
> > read back>9.9 (external meter shows around 1:1). At 10-100W setting,
> > output>100W, SWR>9.9. HI REFL message displayed.
> >
> > Unit was previously working fine for several months.
> >
> > Troubleshooting procedure I used:
> >
> > 1) Disassembled KPA100 from radio (but still connected).
> > Repeated test using 50 ohm dummy load, same results.
> > SWR reading>9.9
> >
> > 2) Set to 40M, 7200 kHz, set power to 5W, and made the following KPA100
> > measurements during TUNE cycle:
> > U5-5: 0.2V (VFWD)
> > U5-7: 0.2V
> > U5-3: 2.01V (VREF)
> > U5-1: 2.01V
> >
> > So, I assume the microcontroller is seeing this and measuring a high
> > SWR. HI REFL message was displayed.
> >
> > 3) Using diode check function on Fluke 8021B, measured D16 and D17 in
> > circuit, each showed approx. 0.4 V forward bias, and open reversed.
> > However I am not yet convinced that the diodes are not damaged in some
> > way (see below).
> >
> > 4) I went through the SWR Bridge Null adjustment procedure in the KPA100
> > manual. However, I was unable to get a measurement of 43 kohms on the
> > wiper on R26 to ground, I was only able to get a maximum of 30 kohms,
> > and with the wiper centered, it read about 23 k ohms. I left both R26
> > and R27 centered.
> >
> > 5) At 5W power, I was able to adjust C1 to obtain a 1.0 SWR reading,
> > noting that C1 appeared to be in almost the same position as before.
> >
> > 6) Set to 40M, 7200 kHz, set power to 5W, and made the following KPA100
> > measurements during TUNE cycle. Indicated power 6.0W, indicated 1.0
> > SWR reading from display. In each case, I allowed about 5 seconds for
> > the output to stabilize before taking each measurement.
> > U5-5: 1.4V
> > U5-7: 1.4V
> > U5-3: 0.02V
> > U5-1: 0.02V
> > U6-6: 2.8V
> > U6-3: 1.4V
> > At this point I am reasonably certain that U5 and U6 are working.
> >
> > 7) set power to 15W, (heard relay switch to KPA100) and made the
> > following KPA100 measurements during TUNE cycle. Indicated power 15W,
> > indicated 1.2 SWR reading from display, external wattmeter showed>20W
> > and 1:1 SWR.
> > U5-5: 2.25V
> > U5-7: 2.25V
> > U5-3: 0.3V
> > U5-1: 0.3V
> > U6-6: 1.41V
> > U6-3: 0.71V
> >
> > 8) set power to 20W, and made the following KPA100 measurements during
> > TUNE cycle. Indicated power 20W, indicated 1.6 SWR reading from
> > display, external wattmeter showed ~40W and 1:1 SWR.
> > U5-7: 2.55V
> > U5-3: 0.6V
> > U5-1: 0.6V
> > U6-6: 1.62V
> > U6-3: 0.81Vmeter showed>40W and 1:1 SWR.
> > U5-5: 2.55V
> > U5-7: 2.55V
> > U5-3: 0.6V
> > U5-1: 0.6V
> > U6-6: 1.62V
> > U6-3: 0.81V
> >
> > 9) set power to 40W, at this point, I was able to re-adjust R26/R27 to
> > match the externally measured output power to the indicated power
> > (within a few watts, and limited by the accuracy of the external power
> > meter).
> > After adjusting R26/R27: Indicated power 42W, indicated 1.8 SWR
> > reading from display, external wattmeter showed ~40W and 1:1 SWR.
> > U5-5: 3.76V
> > U5-7: 3.76V
> > U5-3: 1.15V
> > U5-1: 1.15V
> > U6-6: 2.37V
> > U6-3: 1.18V
> >
> > 10) set power to 60W, Indicated power 60W, indicated 2.3 SWR reading
> > from display, external wattmeter showed ~60W and 1:1 SWR.
> > U5-5: 4.4V
> > U5-7: 4.4V
> > U5-3: 1.72V
> > U5-1: 1.72V
> > U6-6: 2.78V
> > U6-3: 1.39V
> >
> > So, after all of this, my conclusion is that D16 and D17 may be leaky,
> > or somehow defective, and providing invalid voltages to the measuring
> > circuit. I do not believe that U5 or U6 are defective, and it appears
> > that the microcontroller is controlling the power based on the voltages
> > it is seeing.
> >
> > I would appreciate any other opinions or insight, or any other
> > suggestions on what else to check. In the meantime I'll go ahead and
> > order some replacement 1N5711's. Static electricity? Lightning?
> >
> > David AJ4TF
> >
> >
> > ______________________________________________________________
> > 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
> >

Don Wilhelm-4

Re: [K2] Update: K2/100 loss of power control (long post)

David,

Actually using a switch in the antenna line to switch in the dummy load
is best. If you consider that with a PL-259, the center conductor is
connected before the shell, so if there is a charge on the antenna due
to wind, rain or lightning static, it can zap the diodes.

You can get the diodes most anywhere. I usually get mine from Diz -
www.partsandkits.com, inexpensive and he ships quickly.

Thank you for your kind words.

73,
Don

On 6/11/2011 7:48 PM, david wrote:

> Don,
>
> Thanks for confirming my diagnosis. I *usually* remember to disconnect
> the antenna when I am not operating.
>
> I assume that the standard 1N5711 will work, Elecraft doesn't screen
> them for any special characteristics do they?
>
> As always, I'm sure I not the only one that appreciates the knowledge
> you bring to the Elecraft community.
>
> David AJ4TF
>
>
> On Sat, 2011-06-11 at 18:13 -0400, Don Wilhelm wrote:
>> David,
>>
>> Yes, it looks like U5, U6, Q10, Q11 and the associated components are
>> behaving as they should.
>>
>> It certainly could be that D16 and D17 are not either open or shorted,
>> but are not fully functioning as they should. The fact that you could
>> only get the resistance measured at the wiper of R26 as high as 30k does
>> confirm that -- replace the diodes.
>>
>> It also seems from your description that things are a bit intermittent
>> and erratic, so while you are in there to replace the diodes, give the
>> soldering in the wattmeter area (particularly T4) a good inspection and
>> perhaps re-flow the solder with a hot iron (800 degF for the KPA100
>> board), and perhaps add a tiny bit of new solder (actually you are
>> adding a bit of flux).
>>
>> Yes, those diodes are sensitive to lightning surges. Switch the K2
>> antenna to a dummy load when not in use for best results.
>>
>> 73,
>> Don W3FPR
>>
>> On 6/11/2011 4:42 PM, david wrote:
>>> K2/100 s/n 7006
>>> Initial symptom: No control of output power at any knob setting. At
>>> 1-9W setting, output was>10W as measured by external wattmeter, SWR
>>> read back>9.9 (external meter shows around 1:1). At 10-100W setting,
>>> output>100W, SWR>9.9. HI REFL message displayed.
>>>
>>> Unit was previously working fine for several months.
>>>
>>> Troubleshooting procedure I used:
>>>
>>> 1) Disassembled KPA100 from radio (but still connected).
>>> Repeated test using 50 ohm dummy load, same results.
>>> SWR reading>9.9
>>>
>>> 2) Set to 40M, 7200 kHz, set power to 5W, and made the following KPA100
>>> measurements during TUNE cycle:
>>> U5-5: 0.2V (VFWD)
>>> U5-7: 0.2V
>>> U5-3: 2.01V (VREF)
>>> U5-1: 2.01V
>>>
>>> So, I assume the microcontroller is seeing this and measuring a high
>>> SWR. HI REFL message was displayed.
>>>
>>> 3) Using diode check function on Fluke 8021B, measured D16 and D17 in
>>> circuit, each showed approx. 0.4 V forward bias, and open reversed.
>>> However I am not yet convinced that the diodes are not damaged in some
>>> way (see below).
>>>
>>> 4) I went through the SWR Bridge Null adjustment procedure in the KPA100
>>> manual. However, I was unable to get a measurement of 43 kohms on the
>>> wiper on R26 to ground, I was only able to get a maximum of 30 kohms,
>>> and with the wiper centered, it read about 23 k ohms. I left both R26
>>> and R27 centered.
>>>
>>> 5) At 5W power, I was able to adjust C1 to obtain a 1.0 SWR reading,
>>> noting that C1 appeared to be in almost the same position as before.
>>>
>>> 6) Set to 40M, 7200 kHz, set power to 5W, and made the following KPA100
>>> measurements during TUNE cycle. Indicated power 6.0W, indicated 1.0
>>> SWR reading from display. In each case, I allowed about 5 seconds for
>>> the output to stabilize before taking each measurement.
>>> U5-5: 1.4V
>>> U5-7: 1.4V
>>> U5-3: 0.02V
>>> U5-1: 0.02V
>>> U6-6: 2.8V
>>> U6-3: 1.4V
>>> At this point I am reasonably certain that U5 and U6 are working.
>>>
>>> 7) set power to 15W, (heard relay switch to KPA100) and made the
>>> following KPA100 measurements during TUNE cycle. Indicated power 15W,
>>> indicated 1.2 SWR reading from display, external wattmeter showed>20W
>>> and 1:1 SWR.
>>> U5-5: 2.25V
>>> U5-7: 2.25V
>>> U5-3: 0.3V
>>> U5-1: 0.3V
>>> U6-6: 1.41V
>>> U6-3: 0.71V
>>>
>>> 8) set power to 20W, and made the following KPA100 measurements during
>>> TUNE cycle. Indicated power 20W, indicated 1.6 SWR reading from
>>> display, external wattmeter showed ~40W and 1:1 SWR.
>>> U5-7: 2.55V
>>> U5-3: 0.6V
>>> U5-1: 0.6V
>>> U6-6: 1.62V
>>> U6-3: 0.81Vmeter showed>40W and 1:1 SWR.
>>> U5-5: 2.55V
>>> U5-7: 2.55V
>>> U5-3: 0.6V
>>> U5-1: 0.6V
>>> U6-6: 1.62V
>>> U6-3: 0.81V
>>>
>>> 9) set power to 40W, at this point, I was able to re-adjust R26/R27 to
>>> match the externally measured output power to the indicated power
>>> (within a few watts, and limited by the accuracy of the external power
>>> meter).
>>> After adjusting R26/R27: Indicated power 42W, indicated 1.8 SWR
>>> reading from display, external wattmeter showed ~40W and 1:1 SWR.
>>> U5-5: 3.76V
>>> U5-7: 3.76V
>>> U5-3: 1.15V
>>> U5-1: 1.15V
>>> U6-6: 2.37V
>>> U6-3: 1.18V
>>>
>>> 10) set power to 60W, Indicated power 60W, indicated 2.3 SWR reading
>>> from display, external wattmeter showed ~60W and 1:1 SWR.
>>> U5-5: 4.4V
>>> U5-7: 4.4V
>>> U5-3: 1.72V
>>> U5-1: 1.72V
>>> U6-6: 2.78V
>>> U6-3: 1.39V
>>>
>>> So, after all of this, my conclusion is that D16 and D17 may be leaky,
>>> or somehow defective, and providing invalid voltages to the measuring
>>> circuit. I do not believe that U5 or U6 are defective, and it appears
>>> that the microcontroller is controlling the power based on the voltages
>>> it is seeing.
>>>
>>> I would appreciate any other opinions or insight, or any other
>>> suggestions on what else to check. In the meantime I'll go ahead and
>>> order some replacement 1N5711's. Static electricity? Lightning?
>>>
>>> David AJ4TF
>>>
>>>
>>> ______________________________________________________________
>>> 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
>

aj4tf

Re: [K2] Update: K2/100 loss of power control (long post)

In reply to this post by Don Wilhelm-4

Update... I removed D16 and D17.

D16 appears to be defective, it measures about 40 k ohms when reverse
biased.

(At least I think it's D16, I kind of lost track of which one was which
after I cut them out...)

In any case, that isn't good... that's about 30 uA leakage at 1.2V (the
OC voltage of the DMM on the 200K scale). The spec on a 1N5711 is 0.2
uA leakage at 50V.

New diodes are on order.

Thanks again Don,

73,

David AJ4TF

On Sat, 2011-06-11 at 18:13 -0400, Don Wilhelm wrote:

aj4tf

Re: [K2] Update: K2/100 loss of power control (long post)

In reply to this post by aj4tf

New diodes arrived yesterday, thanks to Richard at Elecraft. After
installation and re-calibration of the SWR/wattmeter, everything looks
good, I made two quick contacts on 20m PSK31, one in Greece, the other
in Slovak Republic.

Thanks again Don, Richard, and Elecraft!

73, David AJ4TF

On Sat, 2011-06-11 at 19:48 -0400, david wrote: