K2 T1 tuner operation question

[lstavenhagen]

Hi all,

I got my T1 tuner from Elecraft yesterday (bought the built/tested version to speed things up hi) and have a question about operating it.

When it's tuning, the K2 power output tends to go bonkers. It often gets up to slightly scary levels while the tuner is still negotiating pretty high SWR's. I've had it at full 15W output at the end of the tune, even tho I started off with the power set at 1W.

My question is, is there a way to keep this from happening or at least moderate it a bit? I suspect it's normal for a transmitter's current flow to increase during high SWRs, but I don't want to stress my transmitter any more than necessary.

Or perhaps I should just go with the internal ant. tuner - does it do the same thing?

Other than that it seems to work great....

Tnx es 73,
LS

[Vic K2VCO]

If you do not have the internal tuner or the KPA100, the K2's power output indication is
just based on an RF voltmeter, which assumes a 50 ohm load. If the load is not 50 ohms,
this will be wrong. While the T1 is tuning, the load seen by the K2 will go all over the
place.

So...

Don't worry about it.

On 2/19/2010 8:06 AM, lstavenhagen wrote:

>
> Hi all,
>
> I got my T1 tuner from Elecraft yesterday (bought the built/tested version
> to speed things up hi) and have a question about operating it.
>
> When it's tuning, the K2 power output tends to go bonkers. It often gets up
> to slightly scary levels while the tuner is still negotiating pretty high
> SWR's. I've had it at full 15W output at the end of the tune, even tho I
> started off with the power set at 1W.
>
> My question is, is there a way to keep this from happening or at least
> moderate it a bit? I suspect it's normal for a transmitter's current flow to
> increase during high SWRs, but I don't want to stress my transmitter any
> more than necessary.
>
> Or perhaps I should just go with the internal ant. tuner - does it do the
> same thing?
>
> Other than that it seems to work great....
>
> Tnx es 73,
> LS

--
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco/
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[lstavenhagen]

Ok, thanks Vic.

I was a little suspicious so I tried it a few times watching the current draw in "display" instead. And, while it did fluctuate, it didn't seem to move around as much as the power meter would have suggested....

So sounds normal and won't worry about it as you suggest....

I would have gone with the internal tuner but as the future could hold a K3 eventually, I thought it'd be nice to have a tuner I could reuse with another rig...

Tnx es 73,
LS
W5QD, K2 #6882

[Don Wilhelm-4]

LS,

Vic gave you good info.  If you want a smoother output from the K2 while
the tuner is tuning (and the input load impedance is varying wildly),
about the only 'solution' I know of is to place an attenuator between
the K2 and the tuner - a 5 or 6 dB attenuator with an adequate power
rating will do.  The attenuator provides a more constant load to the K2
during the process.  Unfortunately, you would have to remove the
attenuator after tuning - perhaps a relay to switch it in and out.

73,
Don W3FPR

lstavenhagen wrote:
> Ok, thanks Vic.
>
> I was a little suspicious so I tried it a few times watching the current
> draw in "display" instead. And, while it did fluctuate, it didn't seem to
> move around as much as the power meter would have suggested....
>
> So sounds normal and won't worry about it as you suggest....
>  
>
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Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

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