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K2 KAT2 Issues/Questions

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Paul Locker

K2 KAT2 Issues/Questions

I have just finished the installation of my kat2 I got at Dayton. I am seeing a
high current warning for any band I use above 2 watts. I tried the other
antenna position and noticed it resulted in a different swr. I changed my
ground and that didn't improve the high current warning as I read in the manual
that it could be an issue.

Is there anything specific I need to check or do to start my troubleshooting?

Paul
k4pml

"Don't forget to take the right Path"

-JRDL

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Don Wilhelm-4

Re: K2 KAT2 Issues/Questions

Paul,

Not quite enough information yet to give you a positive answer.
Are you using the KAT2 in the ATU CAL menu setting? If not, what do you
have connected to the ANT jack(s) - hopefully a dummy load. If it is
other than a dummy load, what happens with a dummy load attached?
Did you obtain a good null when you balanced the KAT2 wattmeter? If
not, that is the starting point, even if that is not the problem source.

73,
Don W3FPR

Paul Locker wrote:

> I have just finished the installation of my kat2 I got at Dayton. I am seeing a
> high current warning for any band I use above 2 watts. I tried the other
> antenna position and noticed it resulted in a different swr. I changed my
> ground and that didn't improve the high current warning as I read in the manual
> that it could be an issue.
>
>
> Is there anything specific I need to check or do to start my troubleshooting?
>
> Paul
> k4pml
>
>
> "Don't forget to take the right Path"
>
> -JRDL
>
>
>
>
> ______________________________________________________________
> 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

Paul Locker

Re: K2 KAT2 Issues/Questions

Don et all,
I've had a dummy load connected and still get a high current message. With the
same dummy load, the ATU struggles to find a match for ant1, however for ant2 it
finds a match with out issues. For my null, I got 006.

This evening I'm going to go back and redo the CALn setting.

Thank you for your time on the list.

Paul

"Don't forget to take the right Path"

-JRDL

________________________________
From: Don Wilhelm <[hidden email]>
To: Paul Locker <[hidden email]>
Cc: [hidden email]
Sent: Fri, July 16, 2010 8:01:57 PM
Subject: Re: [Elecraft] K2 KAT2 Issues/Questions

Paul,

Not quite enough information yet to give you a positive answer.
Are you using the KAT2 in the ATU CAL menu setting? If not, what do you have
connected to the ANT jack(s) - hopefully a dummy load. If it is other than a
dummy load, what happens with a dummy load attached?
Did you obtain a good null when you balanced the KAT2 wattmeter? If not, that
is the starting point, even if that is not the problem source.

73,
Don W3FPR

Paul Locker wrote:

> I have just finished the installation of my kat2 I got at Dayton. I am seeing
>a high current warning for any band I use above 2 watts. I tried the other
>antenna position and noticed it resulted in a different swr. I changed my
>ground and that didn't improve the high current warning as I read in the manual
>that it could be an issue.
>
>
> Is there anything specific I need to check or do to start my troubleshooting?
>
> Paul
> k4pml
>
>
> "Don't forget to take the right Path"
>
> -JRDL
>
>
>
> ______________________________________________________________
> 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 KAT2 Issues/Questions

Paul,

If you got a null reading of 006, there is no sense in re-doing it -
that is sufficiently low.
Do the procedures below in the order listed. Stop when one does not
produce the expected result. Each step depends on the one prior to it.

Put the KAT2 in CALn, CAL P or CAL S and then remove the coax from the
K2 RF Board (but connect a 50 ohm dummy load to ANT1.
Measure the resistance between the KAT2 input coax and ground - it
should read 50 ohms (just like your dummy load). If that is not the
case, you likely have a soldering problem at one of the relays.

Ignoring the potential relay problem for a bit, it would be a good idea
to verify the wattmeter. Set the KAT2 to ANT1 and then power off and
separate the KAT2 Control Board from the LC board and set the LC board
aside. Make a jumper wire that extends from J4 pin 2 to J5 pin 15 (this
is a long jumper that plugs into the 2nd pin from the extreme ends of J4
and J5). That bypasses the L/C section of the KAT2 completely.

Measure the resistance between the center conductor of the input coax
and the center conductor of the ANT1 jack - it should be very low
resistance. If that is true, then go on to the next step - otherwise
stop and let me know what you find.

Now, connect a dummy load to the ANT1 jack. As a sanity check, measure
the resistance from the center conductor of the input coax and the
shield - it should be 50 ohms, if it is not, find the problem before
proceeding.

If you measured 50 ohms in the step above, connect the input coax to the
RF Board and try a TUNE with the Power knob set to greater than 2
watts. You should have about 2 watts output. Next set the menu ATU
parameter to CAL P and connect a wattmeter that you trust at the 2 watt
level between the ANT1 jack and the dummy load, and do a TUNE. Adjust
R1 (FWD) to make the K2 display match your external wattmeter.

If the above procedure is successful, remove the jumper and mate the L/C
board to the control board and repeat the procedure. The results should
be almost the same, but you may have to tweak the R1 pot a bit because
there is some residual impedance in the L/C section of the KAT2.

If you got this far, you are almost done (and all is OK). Set the REFL
pot to the same physical position as the FWD pot and put everything back
in order - you are done.

Let us know where the steps above fail. What works as well as where it
fails is important.

73,
Don W3FPR

Paul Locker wrote:

> Don et all,
> I've had a dummy load connected and still get a high current message. With the
> same dummy load, the ATU struggles to find a match for ant1, however for ant2 it
> finds a match with out issues. For my null, I got 006.
>
>
> This evening I'm going to go back and redo the CALn setting.
>
>
> Thank you for your time on the list.
>
>
> Paul
>
>
> "Don't forget to take the right Path"
>
> -JRDL
>
>
>
>
> ________________________________
> From: Don Wilhelm <[hidden email]>
> To: Paul Locker <[hidden email]>
> Cc: [hidden email]
> Sent: Fri, July 16, 2010 8:01:57 PM
> Subject: Re: [Elecraft] K2 KAT2 Issues/Questions
>
> Paul,
>
> Not quite enough information yet to give you a positive answer.
> Are you using the KAT2 in the ATU CAL menu setting? If not, what do you have
> connected to the ANT jack(s) - hopefully a dummy load. If it is other than a
> dummy load, what happens with a dummy load attached?
> Did you obtain a good null when you balanced the KAT2 wattmeter? If not, that
> is the starting point, even if that is not the problem source.
>
> 73,
> Don W3FPR
>
> Paul Locker wrote:
>
>> I have just finished the installation of my kat2 I got at Dayton. I am seeing
>> a high current warning for any band I use above 2 watts. I tried the other
>> antenna position and noticed it resulted in a different swr. I changed my
>> ground and that didn't improve the high current warning as I read in the manual
>> that it could be an issue.
>>
>>
>> Is there anything specific I need to check or do to start my troubleshooting?
>>
>> Paul
>> k4pml
>>
>>
>> "Don't forget to take the right Path"
>>
>> -JRDL
>>
>>
>>
>> ______________________________________________________________
>> 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
>
>

Paul Locker

Re: K2 KAT2 Issues/Questions

Don,

I followed your steps outlined and it looks good. The issue could be me
trusting my watt meter. I think it's time I invested in a new watt meter.
Tomorrow I hope to spend some time testing it on the air.

Thank you again for your help.

Paul
k4pml

Put the KAT2 in CALn, CAL P or CAL S and then remove the coax from the K2 RF
Board (but connect a 50 ohm dummy load to ANT1.
Measure the resistance between the KAT2 input coax and ground - it should read
50 ohms (just like your dummy load). If that is not the case, you likely have
a soldering problem at one of the relays.

## Ant1 measures 51 ohms resistance at the KAT2 input coax,ground

Ignoring the potential relay problem for a bit, it would be a good idea to
verify the wattmeter. Set the KAT2 to ANT1 and then power off and separate the
KAT2 Control Board from the LC board and set the LC board aside. Make a jumper
wire that extends from J4 pin 2 to J5 pin 15 (this is a long jumper that plugs
into the 2nd pin from the extreme ends of J4 and J5). That bypasses the L/C
section of the KAT2 completely.

Measure the resistance between the center conductor of the input coax and the
center conductor of the ANT1 jack - it should be very low resistance. If that
is true, then go on to the next step - otherwise stop and let me know what you
find.

## The resistance between the center conductor of the input coax and the center
conductor of the ANT1 jack is .1 ohms.

Now, connect a dummy load to the ANT1 jack. As a sanity check, measure the
resistance from the center conductor of the input coax and the shield - it
should be 50 ohms, if it is not, find the problem before proceeding.

## The resistance between the center conductor of the input coax to the shield
is 50 ohms.

If you measured 50 ohms in the step above, connect the input coax to the RF
Board and try a TUNE with the Power knob set to greater than 2 watts. You
should have about 2 watts output. Next set the menu ATU parameter to CAL P
and connect a wattmeter that you trust at the 2 watt level between the ANT1
jack and the dummy load, and do a TUNE. Adjust R1 (FWD) to make the K2 display
match your external wattmeter.

If the above procedure is successful, remove the jumper and mate the L/C board
to the control board and repeat the procedure. The results should be almost
the same, but you may have to tweak the R1 pot a bit because there is some
residual impedance in the L/C section of the KAT2.

## This worked fine this time.

"Don't forget to take the right Path"

-JRDL

________________________________
From: Don Wilhelm <[hidden email]>
To: Paul Locker <[hidden email]>
Cc: [hidden email]
Sent: Fri, July 16, 2010 10:30:59 PM
Subject: Re: [Elecraft] K2 KAT2 Issues/Questions

Paul,

If you got a null reading of 006, there is no sense in re-doing it - that is
sufficiently low.
Do the procedures below in the order listed. Stop when one does not produce the
expected result. Each step depends on the one prior to it.

Put the KAT2 in CALn, CAL P or CAL S and then remove the coax from the K2 RF
Board (but connect a 50 ohm dummy load to ANT1.
Measure the resistance between the KAT2 input coax and ground - it should read
50 ohms (just like your dummy load). If that is not the case, you likely have a
soldering problem at one of the relays.

Ignoring the potential relay problem for a bit, it would be a good idea to
verify the wattmeter. Set the KAT2 to ANT1 and then power off and separate the
KAT2 Control Board from the LC board and set the LC board aside. Make a jumper
wire that extends from J4 pin 2 to J5 pin 15 (this is a long jumper that plugs
into the 2nd pin from the extreme ends of J4 and J5). That bypasses the L/C
section of the KAT2 completely.

Measure the resistance between the center conductor of the input coax and the
center conductor of the ANT1 jack - it should be very low resistance. If that
is true, then go on to the next step - otherwise stop and let me know what you
find.

Now, connect a dummy load to the ANT1 jack. As a sanity check, measure the
resistance from the center conductor of the input coax and the shield - it
should be 50 ohms, if it is not, find the problem before proceeding.

If you measured 50 ohms in the step above, connect the input coax to the RF
Board and try a TUNE with the Power knob set to greater than 2 watts. You
should have about 2 watts output. Next set the menu ATU parameter to CAL P and
connect a wattmeter that you trust at the 2 watt level between the ANT1 jack and
the dummy load, and do a TUNE. Adjust R1 (FWD) to make the K2 display match
your external wattmeter.

If the above procedure is successful, remove the jumper and mate the L/C board
to the control board and repeat the procedure. The results should be almost the
same, but you may have to tweak the R1 pot a bit because there is some residual
impedance in the L/C section of the KAT2.

If you got this far, you are almost done (and all is OK). Set the REFL pot to
the same physical position as the FWD pot and put everything back in order - you
are done.

Let us know where the steps above fail. What works as well as where it fails is
important.

73,
Don W3FPR

Paul Locker wrote:

> Don et all,
> I've had a dummy load connected and still get a high current message. With the
>same dummy load, the ATU struggles to find a match for ant1, however for ant2 it
>finds a match with out issues. For my null, I got 006.
>
>
> This evening I'm going to go back and redo the CALn setting.
>
>
> Thank you for your time on the list.
>
>
> Paul
>
>
> "Don't forget to take the right Path"
>
> -JRDL
>
>
>
>
> ________________________________
> From: Don Wilhelm <[hidden email]>
> To: Paul Locker <[hidden email]>
> Cc: [hidden email]
> Sent: Fri, July 16, 2010 8:01:57 PM
> Subject: Re: [Elecraft] K2 KAT2 Issues/Questions
>
> Paul,
>
> Not quite enough information yet to give you a positive answer.
> Are you using the KAT2 in the ATU CAL menu setting? If not, what do you have
>connected to the ANT jack(s) - hopefully a dummy load. If it is other than a
>dummy load, what happens with a dummy load attached?
> Did you obtain a good null when you balanced the KAT2 wattmeter? If not, that
>is the starting point, even if that is not the problem source.
>
> 73,
> Don W3FPR
>
> Paul Locker wrote:
>
>> I have just finished the installation of my kat2 I got at Dayton. I am seeing
>>a high current warning for any band I use above 2 watts. I tried the other
>>antenna position and noticed it resulted in a different swr. I changed my
>>ground and that didn't improve the high current warning as I read in the manual
>>that it could be an issue.
>>
>>
>> Is there anything specific I need to check or do to start my troubleshooting?
>>
>> Paul
>> k4pml
>>
>>
>> "Don't forget to take the right Path"
>>
>> -JRDL
>>
>>
>>
>> ______________________________________________________________
>> 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
>
>

Don Wilhelm-4

Re: K2 KAT2 Issues/Questions

Paul,

Good to hear you were successful.
Yes, many amateur grade wattmeters are not accurate at low power.
Remember that those with analog meters have an accuracy spec based on
"percentage of full scale" - that is even true of the much revered Bird
meters which are speced at 5% of full scale - immediately after
calibration (many amateur grade meters are speced at 20%) On a 100 watt
scale, 5% is 5 watts *anywhere* on the scale! That fact makes measuring
a 2 watt signal level problematic. The meter can read anywhere between
2 watts (plus or minus) 5 watts and still be correct - the student
should "do the math". :-)

73,
Don W3FPR

Paul Locker wrote:

> Don,
>
> I followed your steps outlined and it looks good. The issue could be me
> trusting my watt meter. I think it's time I invested in a new watt meter.
> Tomorrow I hope to spend some time testing it on the air.
>
> Thank you again for your help.
>
> Paul
> k4pml
>
>