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K1 build question: T1, turn count method.

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John Harper

K1 build question: T1, turn count method.

Why would you choose not correct a known error?

Correct it and rule it out as a possible culprit in the event you have a
problem with the radio. If you don't correct it, and end up having a
problem, you'll wonder....

John AE5X
https://ae5x.blogspot.com

> Any guidance on whether I should correct this is welcome.
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Elecraft mailing list

Re: K1 build question: T1, turn count method.

John

Fair question as to why not.

I guess it boils down to tolerance in the design. As T1 and T2 are impedance matches maybe my error isn’t going to push things out of tolerance.

That written, the consensus feed back is I have counted the turns wrong on T1 and it’s easy enough to reduce a turn (versus adding one!).

I just completed the front panel tests and so before heading into the VFO alignment, I’ll make the correction.

For all the inductors (such as L9,L10 etc) I measure the inductance before installing them.

Paul

> On May 29, 2020, at 1:31 PM, John Harper <[hidden email]> wrote:
>
> Why would you choose not correct a known error?
>
> Correct it and rule it out as a possible culprit in the event you have a
> problem with the radio. If you don't correct it, and end up having a
> problem, you'll wonder....
>
> John AE5X
> https://ae5x.blogspot.com
>
>> Any guidance on whether I should correct this is welcome.
> ______________________________________________________________
> 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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Don Wilhelm

Re: K1 build question: T1, turn count method.

Paul,

Yes, correct the turns count on T1 and T2 if necessary.
The impedance matching is important for full power output.

You are not the first to miscount the turns on a toroid (adding an extra
turn). Remember that a single wire through the core is one turn and a
full wrap around the core is 2 turns. That is especially important for
the toroids in the LPF on the band board.

73,
Don W3FPR

On 5/29/2020 5:16 PM, Paul Gacek via Elecraft wrote:

Don Wilhelm

Re: K1 build question: T1, turn count method.

In reply to this post by Elecraft mailing list

Paul,

As far as measuring the inductances, the listed values are only average.
Count the toroid turns correctly and there will be no problem.

73,
Don W3FPR

On 5/29/2020 5:16 PM, Paul Gacek via Elecraft wrote:

> John
>
> Fair question as to why not.
>
> I guess it boils down to tolerance in the design. As T1 and T2 are impedance matches maybe my error isn’t going to push things out of tolerance.
>
> That written, the consensus feed back is I have counted the turns wrong on T1 and it’s easy enough to reduce a turn (versus adding one!).
>
> I just completed the front panel tests and so before heading into the VFO alignment, I’ll make the correction.
>
> For all the inductors (such as L9,L10 etc) I measure the inductance before installing them.
>
> Paul
>
>> On May 29, 2020, at 1:31 PM, John Harper <[hidden email]> wrote:
>>
>> Why would you choose not correct a known error?
>>
>> Correct it and rule it out as a possible culprit in the event you have a
>> problem with the radio. If you don't correct it, and end up having a
>> problem, you'll wonder....
>>
>> John AE5X
>> https://ae5x.blogspot.com
>>
>>> Any guidance on whether I should correct this is welcome.
>> ______________________________________________________________
>> 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]
>

Vic Rosenthal

Re: K1 build question: T1, turn count method.

In reply to this post by Elecraft mailing list

Measuring the inductance is not a good approach unless you have a way of measuring it at a specific frequency. The toroid material’s effect on the inductance of the finished coil varies with frequency, and most LC meters use a frequency below the HF range.

Victor 4X6GP

> On 30 May 2020, at 0:16, Paul Gacek via Elecraft <[hidden email]> wrote:
>
> John
>
> Fair question as to why not.
>
> I guess it boils down to tolerance in the design. As T1 and T2 are impedance matches maybe my error isn’t going to push things out of tolerance.
>
> That written, the consensus feed back is I have counted the turns wrong on T1 and it’s easy enough to reduce a turn (versus adding one!).
>
> I just completed the front panel tests and so before heading into the VFO alignment, I’ll make the correction.
>
> For all the inductors (such as L9,L10 etc) I measure the inductance before installing them.
>
> Paul
>
>> On May 29, 2020, at 1:31 PM, John Harper <[hidden email]> wrote:
>>
>> Why would you choose not correct a known error?
>>
>> Correct it and rule it out as a possible culprit in the event you have a
>> problem with the radio. If you don't correct it, and end up having a
>> problem, you'll wonder....
>>
>> John AE5X
>> https://ae5x.blogspot.com
>>
>>> Any guidance on whether I should correct this is welcome.
>> ______________________________________________________________
>> 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]