Elecraft › [K1]

K1- KAT1 SWR Bridge Adjustment--no voltage variation.

Classic

List

Threaded

5 messages Options

Richard-3

K1- KAT1 SWR Bridge Adjustment--no voltage variation.

I'm in the final stages of testing/adjusting a newly built KAT1 board in
a 2-band K1 (RF Board rev E). In the SWR Bridge adjustment task, I'm
not seeing any voltage change beyond what seems to be random noise. I'm
using a plastic adjustment tool and a DMM.

I'm concerned I may have installed trimmer C9 backwards. It has a
broad/wide side and a blunted narrower side. Instructions call for the
flat side to the left. The broad side seems curved, so I placed the
narrow side to the left, wide side to the right.

Instructions indicated to follow the pattern on the board for C9
installation, but my board has two holes and what look like horizontal
parentheses with no indication of broad, flat or narrow sides.

The manual notes that the null may be sharp. I'm not seeing it.

Thanks for any advice.

Rich
NU6T
______________________________________________________________
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: K1- KAT1 SWR Bridge Adjustment--no voltage variation.

Rich,

You have the capacitor mounted correctly, the narrow end is flat while
the broad end is rounded.
You are also correct to adjust it with a non-metallic tool - both sides
of the capacitor are above ground and will be de-tuned if you touch
either of the plates.

I suspect your problem is not with the capacitor, but with the bi-filar
wound toroid. Check that carefully for the proper leads in the right
holes, and make sure the leads are well tinned - you should be able to
see a bit of tinned lead above the board - if not, be suspicious of it,
even to the point of removing it and re-tinning the leads..

73,
Don W3FPR

On 12/30/2010 5:42 PM, Rich NU6T wrote:

> I'm in the final stages of testing/adjusting a newly built KAT1 board in
> a 2-band K1 (RF Board rev E). In the SWR Bridge adjustment task, I'm
> not seeing any voltage change beyond what seems to be random noise. I'm
> using a plastic adjustment tool and a DMM.
>
> I'm concerned I may have installed trimmer C9 backwards. It has a
> broad/wide side and a blunted narrower side. Instructions call for the
> flat side to the left. The broad side seems curved, so I placed the
> narrow side to the left, wide side to the right.
>
> Instructions indicated to follow the pattern on the board for C9
> installation, but my board has two holes and what look like horizontal
> parentheses with no indication of broad, flat or narrow sides.
>
> The manual notes that the null may be sharp. I'm not seeing it.
>
> Thanks for any advice.
>
> Rich
> NU6T
> ______________________________________________________________
> 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

Byron N6NUL

Re: K1- KAT1 SWR Bridge Adjustment--no voltage variation.

In reply to this post by Richard-3

Hi Rich,

Have you remembered to move the RF jumper to the KAT1 position? I
made that mistake.

73, Byron N6NUL

On Thu, Dec 30, 2010 at 2:42 PM, Rich NU6T <[hidden email]> wrote:
> I'm in the final stages of testing/adjusting a newly built KAT1 board in
> a 2-band K1 (RF Board rev E). In the SWR Bridge adjustment task, I'm
> not seeing any voltage change beyond what seems to be random noise. I'm
> using a plastic adjustment tool and a DMM.

--
- Northern California Contest Club
- CU in the 2011 Cal QSO Party 1-2 Oct 2011
- www.cqp.org
______________________________________________________________
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

Richard-3

Re: K1- KAT1 SWR Bridge Adjustment--no voltage variation.

Bryon, while I have neglected important things like that before, not
this time <grin>.

Thanks.
Rich
NU6T

On 12/30/2010 4:05 PM, Byron Servies wrote:

> Hi Rich,
>
> Have you remembered to move the RF jumper to the KAT1 position? I
> made that mistake.
>
> 73, Byron N6NUL
>
> On Thu, Dec 30, 2010 at 2:42 PM, Rich NU6T<[hidden email]> wrote:
>> I'm in the final stages of testing/adjusting a newly built KAT1 board in
>> a 2-band K1 (RF Board rev E). In the SWR Bridge adjustment task, I'm
>> not seeing any voltage change beyond what seems to be random noise. I'm
>> using a plastic adjustment tool and a DMM.

Richard-3

Re: K1- KAT1 SWR Bridge Adjustment--no voltage variation.

In reply to this post by Don Wilhelm-4

Thanks, Don. I'll re-check the bi-filar toroid.

73
Rich
NU6T

On 12/30/2010 3:50 PM, Don Wilhelm wrote:

> Rich,
>
> You have the capacitor mounted correctly, the narrow end is flat while
> the broad end is rounded.
> You are also correct to adjust it with a non-metallic tool - both
> sides of the capacitor are above ground and will be de-tuned if you
> touch either of the plates.
>
> I suspect your problem is not with the capacitor, but with the
> bi-filar wound toroid. Check that carefully for the proper leads in
> the right holes, and make sure the leads are well tinned - you should
> be able to see a bit of tinned lead above the board - if not, be
> suspicious of it, even to the point of removing it and re-tinning the
> leads..
>
> 73,
> Don W3FPR
>
> On 12/30/2010 5:42 PM, Rich NU6T wrote:
>> I'm in the final stages of testing/adjusting a newly built KAT1 board in
>> a 2-band K1 (RF Board rev E). In the SWR Bridge adjustment task, I'm
>> not seeing any voltage change beyond what seems to be random noise. I'm
>> using a plastic adjustment tool and a DMM.
>>
>> I'm concerned I may have installed trimmer C9 backwards. It has a
>> broad/wide side and a blunted narrower side. Instructions call for the
>> flat side to the left. The broad side seems curved, so I placed the
>> narrow side to the left, wide side to the right.
>>
>> Instructions indicated to follow the pattern on the board for C9
>> installation, but my board has two holes and what look like horizontal
>> parentheses with no indication of broad, flat or narrow sides.
>>
>> The manual notes that the null may be sharp. I'm not seeing it.
>>
>> Thanks for any advice.
>>
>> Rich
>> NU6T
>> ______________________________________________________________
>> 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
>>
>
>