Elecraft

KAT500 producing S4-5-birdie on 28004.5

Classic

List

Threaded

5 messages Options

Arie Kleingeld PA3A-2

KAT500 producing S4-5-birdie on 28004.5

Hi all,

KAT500 + KPA500 connected to K3 through coax and elecraft
interfacecables. NO antenna connected to KAT500 (all 3 connectors open)
KAT500 and K3 connected to same DC-supply.

KPA500 off (AC cord disconnected)

Results:
KAT500 switched on, Mode = auto, ANT = 1, no antenna connected: *S4
birdie on 28004.5 kHz* measured by K3

test 1:
- Changing ANT connector on K3: birdie gone.
- Change antennaconnected on K3 back: birdie S4 again
- Change to other antennaconnectors on KAT500 makes very little
difference: <0.3dB Measured on dBV meter of K3 with AGC off
- Disconnecting the elecraft interface cables makes NO difference. Keep
them disconnected for further tests.

test 2:
- Switch off KAT500 (hold mode switch): birdie drops <0.5dB
- Disconnect DC from KAT500: birdie is gone. (proof that is has to do
with the KAT500)

test 3:
- KAT500 switched on again
- Connect dummyload on ANT 1 of KAT500 with KAT500 on: birdielevel goes
UP +2dB (as compared to no dummyload connected in tests 1 and 2).
S-meter now now has gone up to S5.
- then switch off KAT500: birdielevel drops DOWN -10.5dB
- switch off KAT500: birdie gone

Can anyone reproduce this?

I have not checked all other frequencies, so this might be the only one.
Still this is a birdie that I cannot ignore.

73
Arie PA3A

______________________________________________________________
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

Tony Scandurra K4QE

Re: KAT500 producing S4-5-birdie on 28004.5

Arie,

Please see the firmware release notes here:

http://www.elecraft.com/KAT500/kat500_software.htm

73, Tony K4QE

On Sat, Jun 29, 2013 at 7:02 AM, Arie Kleingeld PA3A <[hidden email]> wrote:

> Hi all,
>
> KAT500 + KPA500 connected to K3 through coax and elecraft interfacecables.
> NO antenna connected to KAT500 (all 3 connectors open)
> KAT500 and K3 connected to same DC-supply.
>
> KPA500 off (AC cord disconnected)
>
> Results:
> KAT500 switched on, Mode = auto, ANT = 1, no antenna connected: *S4 birdie
> on 28004.5 kHz* measured by K3
>
> test 1:
> - Changing ANT connector on K3: birdie gone.
> - Change antennaconnected on K3 back: birdie S4 again
> - Change to other antennaconnectors on KAT500 makes very little
> difference: <0.3dB Measured on dBV meter of K3 with AGC off
> - Disconnecting the elecraft interface cables makes NO difference. Keep
> them disconnected for further tests.
>
> test 2:
> - Switch off KAT500 (hold mode switch): birdie drops <0.5dB
> - Disconnect DC from KAT500: birdie is gone. (proof that is has to do with
> the KAT500)
>
> test 3:
> - KAT500 switched on again
> - Connect dummyload on ANT 1 of KAT500 with KAT500 on: birdielevel goes UP
> +2dB (as compared to no dummyload connected in tests 1 and 2). S-meter now
> now has gone up to S5.
> - then switch off KAT500: birdielevel drops DOWN -10.5dB
> - switch off KAT500: birdie gone
>
> Can anyone reproduce this?
>
> I have not checked all other frequencies, so this might be the only one.
> Still this is a birdie that I cannot ignore.
>
> 73
> Arie PA3A
>
>
>
>
> ______________________________**______________________________**__
> Elecraft mailing list
> Home: http://mailman.qth.net/**mailman/listinfo/elecraft<http://mailman.qth.net/mailman/listinfo/elecraft>
> Help: http://mailman.qth.net/mmfaq.**htm<http://mailman.qth.net/mmfaq.htm>
> Post: mailto:[hidden email].**net <[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

Willard Myers

Re: KAT500 producing S4-5-birdie on 28004.5

In reply to this post by Arie Kleingeld PA3A-2

Aire,

Yes, that spurious signal on 28.004.5 is real and generated within the KAT500. Recent KAT500 beta firmware optionally shuts off an oscillator inside the KAT500 to suppress the spur. The oscillator is automatically turned back on by a number of events, such as pressing a button or transmitting.

The oscillator is also turned on by activity on the KAT500 serial port, which means that software like mine that polls the KAT500 to keep track of antenna port selection also keeps that spur alive. Sigh.

Bill, K1GQ

On 2013.06.29, at 07:02, Arie Kleingeld PA3A <[hidden email]> wrote:

> Hi all,
>
> KAT500 + KPA500 connected to K3 through coax and elecraft interfacecables. NO antenna connected to KAT500 (all 3 connectors open)
> KAT500 and K3 connected to same DC-supply.
>
> KPA500 off (AC cord disconnected)
>
> Results:
> KAT500 switched on, Mode = auto, ANT = 1, no antenna connected: *S4 birdie on 28004.5 kHz* measured by K3
>
> test 1:
> - Changing ANT connector on K3: birdie gone.
> - Change antennaconnected on K3 back: birdie S4 again
> - Change to other antennaconnectors on KAT500 makes very little difference: <0.3dB Measured on dBV meter of K3 with AGC off
> - Disconnecting the elecraft interface cables makes NO difference. Keep them disconnected for further tests.
>
> test 2:
> - Switch off KAT500 (hold mode switch): birdie drops <0.5dB
> - Disconnect DC from KAT500: birdie is gone. (proof that is has to do with the KAT500)
>
> test 3:
> - KAT500 switched on again
> - Connect dummyload on ANT 1 of KAT500 with KAT500 on: birdielevel goes UP +2dB (as compared to no dummyload connected in tests 1 and 2). S-meter now now has gone up to S5.
> - then switch off KAT500: birdielevel drops DOWN -10.5dB
> - switch off KAT500: birdie gone
>
> Can anyone reproduce this?
>
> I have not checked all other frequencies, so this might be the only one. Still this is a birdie that I cannot ignore.
>
> 73
> Arie PA3A
>
>
>
>
> ______________________________________________________________
> 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

Arie Kleingeld PA3A-2

Re: KAT500 producing S4-5-birdie on 28004.5

In reply to this post by Arie Kleingeld PA3A-2

Thanks for all info on the KAT500 beta FW.

Sorry, I was not aware that the problem had been bypassed in a beta version.
Am a new KAT / KPA 500 user.

73
Arie PA3A
K3 #1255

______________________________________________________________
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

Arthur Nienhouse

Re: KAT500 producing S4-5-birdie on 28004.5

In reply to this post by Willard Myers

/*Aire my KAT500 antenna tuner has the same issue with the signal on
28.004.5

Regards
Art
ka9zap

*/

On 6/29/2013 6:11 AM, K1GQ wrote:

> Aire,
>
> Yes, that spurious signal on 28.004.5 is real and generated within the KAT500. Recent KAT500 beta firmware optionally shuts off an oscillator inside the KAT500 to suppress the spur. The oscillator is automatically turned back on by a number of events, such as pressing a button or transmitting.
>
> The oscillator is also turned on by activity on the KAT500 serial port, which means that software like mine that polls the KAT500 to keep track of antenna port selection also keeps that spur alive. Sigh.
>
> Bill, K1GQ
>
> On 2013.06.29, at 07:02, Arie Kleingeld PA3A <[hidden email]> wrote:
>
>> Hi all,
>>
>> KAT500 + KPA500 connected to K3 through coax and elecraft interfacecables. NO antenna connected to KAT500 (all 3 connectors open)
>> KAT500 and K3 connected to same DC-supply.
>>
>> KPA500 off (AC cord disconnected)
>>
>> Results:
>> KAT500 switched on, Mode = auto, ANT = 1, no antenna connected: *S4 birdie on 28004.5 kHz* measured by K3
>>
>> test 1:
>> - Changing ANT connector on K3: birdie gone.
>> - Change antennaconnected on K3 back: birdie S4 again
>> - Change to other antennaconnectors on KAT500 makes very little difference: <0.3dB Measured on dBV meter of K3 with AGC off
>> - Disconnecting the elecraft interface cables makes NO difference. Keep them disconnected for further tests.
>>
>> test 2:
>> - Switch off KAT500 (hold mode switch): birdie drops <0.5dB
>> - Disconnect DC from KAT500: birdie is gone. (proof that is has to do with the KAT500)
>>
>> test 3:
>> - KAT500 switched on again
>> - Connect dummyload on ANT 1 of KAT500 with KAT500 on: birdielevel goes UP +2dB (as compared to no dummyload connected in tests 1 and 2). S-meter now now has gone up to S5.
>> - then switch off KAT500: birdielevel drops DOWN -10.5dB
>> - switch off KAT500: birdie gone
>>
>> Can anyone reproduce this?
>>
>> I have not checked all other frequencies, so this might be the only one. Still this is a birdie that I cannot ignore.
>>
>> 73
>> Arie PA3A
>>
>>
>>
>>
>> ______________________________________________________________
>> 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