Elecraft

W1

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Ed Lambert-4

W1

It is probably necessary to restate my question with more precision.

1. I have calibrated the K3s using Elecraft K3 Utility

2. I have carefully calibrated the W1 using the DDM method with a good
quality DDM.

3. Comparing the results, I see that the W1 consistently calculates
power about 1 dB higher than the K3s. Statistically, I would have expected
them to be closer. From the W1 specifications, and not knowing the K3s power
accuracy specifications, it seems that, possibly, the K3s is displaying
about 3 sigma low and the W1 3 sigma high, which is unlikely.

4. The question: Should the K3s be calibrated from the W1 or should
the W1 be calibrated from the K3s?

(There could be a detailed, separate discussion of the meaning of "average"
power and "PEP" as used in the W1 programming reference. It is my belief
that the two should be the same thing if using a cw signal and the FCC
definition of "PEP". It would be interesting to know what is going on in the
K3s transmitter gain calibration process. It seems like there is an internal
power measurement process and the gain is being set against that. Does that
internal measurement process have accuracy equivalent to the W1 or vice
versa?)

Ed

KD3Y

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Bob Novas

Re: W1

Ed - What are you putting the output power to -- a dummy load or an
antenna? Do you have the KAT internal antenna tuner? If there is an SWR on
the antenna line that the KAT is tuning out for the transceiver, then the W1
will read forward power and reverse power on the antenna line whereas the K3
will read output power. If you subtract the W1's reverse power reading from
the W1's forward power reading, does that compare to the K3's power reading?
Try reading the two power meters into a good dummy load. Then the K3 reading
and the W1 forward reading should be equal. Bob - W3DK

> -----Original Message-----
> From: Elecraft [mailto:[hidden email]] On Behalf Of Ed
> Lambert
> Sent: Thursday, December 31, 2015 6:33 AM
> To: [hidden email]
> Subject: [Elecraft] W1
>
> It is probably necessary to restate my question with more precision.
>
> 1. I have calibrated the K3s using Elecraft K3 Utility
>
> 2. I have carefully calibrated the W1 using the DDM method with a

good
> quality DDM.
>
> 3. Comparing the results, I see that the W1 consistently calculates
> power about 1 dB higher than the K3s. Statistically, I would have expected
them
> to be closer. From the W1 specifications, and not knowing the K3s power
> accuracy specifications, it seems that, possibly, the K3s is displaying
about 3
> sigma low and the W1 3 sigma high, which is unlikely.
>
> 4. The question: Should the K3s be calibrated from the W1 or should
> the W1 be calibrated from the K3s?
>
> (There could be a detailed, separate discussion of the meaning of
"average"
> power and "PEP" as used in the W1 programming reference. It is my belief
that
> the two should be the same thing if using a cw signal and the FCC
definition of
> "PEP". It would be interesting to know what is going on in the K3s
transmitter
> gain calibration process. It seems like there is an internal power
measurement
> process and the gain is being set against that. Does that internal
measurement

> process have accuracy equivalent to the W1 or vice
> versa?)
>
>
>
> Ed
>
> KD3Y
>
> ______________________________________________________________
> Elecraft mailing list
> 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

Message
> delivered to [hidden email]

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John Oppenheimer

Re: W1

In reply to this post by Ed Lambert-4

Hi Ed.

The W1 DC voltage calibration resulted with incorrect reading with my
W1. My hunch is that components have changed since Elecraft established
the TP1 DC calibration voltage almost a decade ago.

I have a KX3F with unchanged factory power calibration. Based on
comments from Wayne, the KX3 is calibrated at 7.0 watts.

My W1 TP1 voltage is 4.812 using a Fluke 87V

Setting up a test bench with KX3 -> W1 -> DL1

Using W1 Utility to display W1 power:
http://www.elecraft.com/software/W1/elecraft_w1_software.htm

TP1 V = 4.812
KX3 power = 7.0 W
W1 power = 7.02
DL1 V = 12.91 = 6.93 watts

The W1 20 dB directional coupler does absorb power, at 7 watts, the
directional coupler will absorb 0.07 watts. Adding 0.07 to the DL1
measurements equals 7.00 watts.

John KN5L
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John Oppenheimer

Re: W1

I performed some additional research, Johnny, VR2XMC, measured TP1 V at
4.82 back in December 2006. Maybe the 4.5 is a typo and should be 4.8:
http://elecraft.365791.n2.nabble.com/some-questions-of-W1-td442330.html

John KN5L

On 12/31/2015 06:22 AM, John Oppenheimer wrote:

> Hi Ed.
>
> The W1 DC voltage calibration resulted with incorrect reading with my
> W1. My hunch is that components have changed since Elecraft established
> the TP1 DC calibration voltage almost a decade ago.
>
> I have a KX3F with unchanged factory power calibration. Based on
> comments from Wayne, the KX3 is calibrated at 7.0 watts.
>
> My W1 TP1 voltage is 4.812 using a Fluke 87V
>
> Setting up a test bench with KX3 -> W1 -> DL1
>
> Using W1 Utility to display W1 power:
> http://www.elecraft.com/software/W1/elecraft_w1_software.htm
>
> TP1 V = 4.812
> KX3 power = 7.0 W
> W1 power = 7.02
> DL1 V = 12.91 = 6.93 watts
>
> The W1 20 dB directional coupler does absorb power, at 7 watts, the
> directional coupler will absorb 0.07 watts. Adding 0.07 to the DL1
> measurements equals 7.00 watts.
>
> John KN5L

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Ed Lambert-4

FW: W1

In reply to this post by John Oppenheimer

John,

Thank you for your response.
My original K3s test setup was per the manual: good quality dummy load (not
the DL1 because of its 20 watt upper limit) with the ATU off. My high
quality dummy load does not have a test point.
After reading your results, I decided to take the DL1 as my "truth model". I
found that the W1 display was 0.8 dB high and the K3s power display was 0.9
dB low. Each one was at the opposite end of the error budget. (sort of like
winning the "losers" lottery).
So, I set up the W1 to match the DL1 up to 20 watts and, surprise, the W1 TP
voltage is now 4.87 volts.
I don't have the W1 software and cabling installed yet. At that time I can
fine tune all of this.
It seems as though a consensus is building that the W1 manual specification
of 4.5 volts is no longer correct, unless there is something "off" with the
W1 internal algorithm.
Good stuff. Thank you everyone for your comments and help.

-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of John
Oppenheimer
Sent: Thursday, December 31, 2015 7:22 AM
To: [hidden email]
Subject: Re: [Elecraft] W1

Hi Ed.

The W1 DC voltage calibration resulted with incorrect reading with my W1. My
hunch is that components have changed since Elecraft established the TP1 DC
calibration voltage almost a decade ago.

I have a KX3F with unchanged factory power calibration. Based on comments
from Wayne, the KX3 is calibrated at 7.0 watts.

My W1 TP1 voltage is 4.812 using a Fluke 87V

Setting up a test bench with KX3 -> W1 -> DL1

Using W1 Utility to display W1 power:
http://www.elecraft.com/software/W1/elecraft_w1_software.htm

TP1 V = 4.812
KX3 power = 7.0 W
W1 power = 7.02
DL1 V = 12.91 = 6.93 watts

The W1 20 dB directional coupler does absorb power, at 7 watts, the
directional coupler will absorb 0.07 watts. Adding 0.07 to the DL1
measurements equals 7.00 watts.

John KN5L
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Robert Nobis - N7RJN

Re: W1

Just wondering. Why is an accuracy within less than 1dB important?

Happy New Year.

73,

Bob Nobis - N7RJN
[hidden email]

> On Dec 31, 2015, at 09:42, Ed Lambert <[hidden email]> wrote:
>
> John,
>
> Thank you for your response.
> My original K3s test setup was per the manual: good quality dummy load (not
> the DL1 because of its 20 watt upper limit) with the ATU off. My high
> quality dummy load does not have a test point.
> After reading your results, I decided to take the DL1 as my "truth model". I
> found that the W1 display was 0.8 dB high and the K3s power display was 0.9
> dB low. Each one was at the opposite end of the error budget. (sort of like
> winning the "losers" lottery).
> So, I set up the W1 to match the DL1 up to 20 watts and, surprise, the W1 TP
> voltage is now 4.87 volts.
> I don't have the W1 software and cabling installed yet. At that time I can
> fine tune all of this.
> It seems as though a consensus is building that the W1 manual specification
> of 4.5 volts is no longer correct, unless there is something "off" with the
> W1 internal algorithm.
> Good stuff. Thank you everyone for your comments and help.
>
> -----Original Message-----
> From: Elecraft [mailto:[hidden email]] On Behalf Of John
> Oppenheimer
> Sent: Thursday, December 31, 2015 7:22 AM
> To: [hidden email]
> Subject: Re: [Elecraft] W1
>
> Hi Ed.
>
> The W1 DC voltage calibration resulted with incorrect reading with my W1. My
> hunch is that components have changed since Elecraft established the TP1 DC
> calibration voltage almost a decade ago.
>
> I have a KX3F with unchanged factory power calibration. Based on comments
> from Wayne, the KX3 is calibrated at 7.0 watts.
>
> My W1 TP1 voltage is 4.812 using a Fluke 87V
>
> Setting up a test bench with KX3 -> W1 -> DL1
>
> Using W1 Utility to display W1 power:
> http://www.elecraft.com/software/W1/elecraft_w1_software.htm
>
> TP1 V = 4.812
> KX3 power = 7.0 W
> W1 power = 7.02
> DL1 V = 12.91 = 6.93 watts
>
> The W1 20 dB directional coupler does absorb power, at 7 watts, the
> directional coupler will absorb 0.07 watts. Adding 0.07 to the DL1
> measurements equals 7.00 watts.
>
> John KN5L
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html Message
> delivered to [hidden email]
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
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> Message delivered to [hidden email]
>

Lewis Phelps

Re: W1

“Because it’s there.”

George Leigh Mallory, 1923, answering the question why he continued to try to climb to the summit of Mt. Everest.

73,

Lew N6LEW

> On Dec 31, 2015, at 8:51 AM, Robert Nobis <[hidden email]> wrote:
>
> Just wondering. Why is an accuracy within less than 1dB important?
>
> Happy New Year.
>
> 73,
>
> Bob Nobis - N7RJN
> [hidden email] <mailto:[hidden email]>
>

Gary Smith-2

Re: W1

In reply to this post by Robert Nobis - N7RJN

Because accuracy is or isn't.

73,

HNY

Gary
KA1J

> Just wondering. Why is an accuracy within less than 1dB important?
>
> Happy New Year.
>
> 73,
>
> Bob Nobis - N7RJN
> [hidden email]
>
>
> > On Dec 31, 2015, at 09:42, Ed Lambert <[hidden email]> wrote:
> >
> > John,
> >
> > Thank you for your response.
> > My original K3s test setup was per the manual: good quality dummy load (not
> > the DL1 because of its 20 watt upper limit) with the ATU off. My high
> > quality dummy load does not have a test point.
> > After reading your results, I decided to take the DL1 as my "truth model". I
> > found that the W1 display was 0.8 dB high and the K3s power display was 0.9
> > dB low. Each one was at the opposite end of the error budget. (sort of like
> > winning the "losers" lottery).
> > So, I set up the W1 to match the DL1 up to 20 watts and, surprise, the W1 TP
> > voltage is now 4.87 volts.
> > I don't have the W1 software and cabling installed yet. At that time I can
> > fine tune all of this.
> > It seems as though a consensus is building that the W1 manual specification
> > of 4.5 volts is no longer correct, unless there is something "off" with the
> > W1 internal algorithm.
> > Good stuff. Thank you everyone for your comments and help.
> >
> > -----Original Message-----
> > From: Elecraft [mailto:[hidden email]] On Behalf Of John
> > Oppenheimer
> > Sent: Thursday, December 31, 2015 7:22 AM
> > To: [hidden email]
> > Subject: Re: [Elecraft] W1
> >
> > Hi Ed.
> >
> > The W1 DC voltage calibration resulted with incorrect reading with my W1. My
> > hunch is that components have changed since Elecraft established the TP1 DC
> > calibration voltage almost a decade ago.
> >
> > I have a KX3F with unchanged factory power calibration. Based on comments
> > from Wayne, the KX3 is calibrated at 7.0 watts.
> >
> > My W1 TP1 voltage is 4.812 using a Fluke 87V
> >
> > Setting up a test bench with KX3 -> W1 -> DL1
> >
> > Using W1 Utility to display W1 power:
> > http://www.elecraft.com/software/W1/elecraft_w1_software.htm
> >
> > TP1 V = 4.812
> > KX3 power = 7.0 W
> > W1 power = 7.02
> > DL1 V = 12.91 = 6.93 watts
> >
> > The W1 20 dB directional coupler does absorb power, at 7 watts, the
> > directional coupler will absorb 0.07 watts. Adding 0.07 to the DL1
> > measurements equals 7.00 watts.
> >
> > John KN5L
> > ______________________________________________________________
> > Elecraft mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:[hidden email]
> >
> > This list hosted by: http://www.qsl.net
> > Please help support this email list: http://www.qsl.net/donate.html Message
> > delivered to [hidden email]
> >
> > ______________________________________________________________
> > Elecraft mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:[hidden email]
> >
> > This list hosted by: http://www.qsl.net
> > Please help support this email list: http://www.qsl.net/donate.html
> > Message delivered to [hidden email]
> >
>
> ______________________________________________________________
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>

Bob McGraw - K4TAX

Re: W1

For the same reason I find the AUTO SPOT function to be in error some 2 Hz.

73
Bob, K4TAX

On 12/31/2015 3:36 PM, Gary Smith wrote:
> Because accuracy is or isn't.
>
> 73,
>
> HNY
>
> Gary
> KA1J

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