K2 Alignment

[G4JQT]

K2 s/n 6905

I have just got to the 40-metre TX alignment and peaked up L1/L2; minor issue/observation.

The power output varies sometimes when [TUNE] is selected. Set to 2W and sometimes it's about 1.5W and sometimes 2.5W.

I've checked the output on a 20 MHz scope and there is no obvious instability. Battery 11.7, volts current about 1.26A when on higher output and about 1.1A when it's jumped to the lower output. I have not seen this change during TUNE, just when hitting TUNE, rx, TUNE, etc.

When adjusting the power control and looking at the output on the scope, there are discrete jumps rather than a smooth variation. Presumably this is normal, but if the power setting is set on the edge of a 'jump' then maybe this is to be expected...? Seems a bit strange is this is the case. Maybe it does not occur in normal use?

I have had a quick look in the archive ("power varies") but not found anything that really matches these symptoms.

Any thoughts?

Thanks and regards,

Ian, G4JQT


     
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[David Pratt]

Nothing to worry about, Ian.  The KAT3 automatically reduces the power
while tuning up to protect the relays.  But you do need to set the power
control to over about 5W or else you will get a "Lo P" warning, which
indicates that the power is set too low for the KAT3 to perform the
tuning operation.

73 de David G4DMP

In a recent message, Ian Liston-Smith <[hidden email]> writes
>
>The power output varies sometimes when [TUNE] is selected. Set to 2W
>and sometimes it's about 1.5W and sometimes 2.5W.
--
 + - - - - - - - - - - - - - - - - - - - +
 | David M Pratt, Kippax, Leeds, England |
 | Website: http://www.g4dmp.fsnet.co.uk |
 + - - - - - - - - - - - - - - - - - - - +



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[Don Wilhelm-4]

  Ian,

What you are seeing in TUNE is normal.  The power control is not as
responsive in TUNE as it is in normal operation.
There is a reason for it - think of those using a manual tuner.

73,
Don W3FPR

On 11/13/2010 6:28 AM, Ian Liston-Smith wrote:

> K2 s/n 6905
>
> I have just got to the 40-metre TX alignment and peaked up L1/L2; minor issue/observation.
>
> The power output varies sometimes when [TUNE] is selected. Set to 2W and sometimes it's about 1.5W and sometimes 2.5W.
>
> I've checked the output on a 20 MHz scope and there is no obvious instability. Battery 11.7, volts current about 1.26A when on higher output and about 1.1A when it's jumped to the lower output. I have not seen this change during TUNE, just when hitting TUNE, rx, TUNE, etc.
>
> When adjusting the power control and looking at the output on the scope, there are discrete jumps rather than a smooth variation. Presumably this is normal, but if the power setting is set on the edge of a 'jump' then maybe this is to be expected...? Seems a bit strange is this is the case. Maybe it does not occur in normal use?
>
> I have had a quick look in the archive ("power varies") but not found anything that really matches these symptoms.
>
> Any thoughts?
>
> Thanks and regards,
>
> Ian, G4JQT
>
>
>    
> ______________________________________________________________
> 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
>

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