[Elecraft] TUNE power, low vs high

[Jack Brindle]

I look at it another way. When I operate QRP I want every milliwatt I can have going to the antenna. As Ron’s post noted, a 2:1 SWR may be indicated as 1.1 when low power is used. That means you are losing significant power, but don’t know it. It teas a short time to crank the power up to 5 or 10 watts, do the tune, then drop down to the power you really want to run. Then you would be sure your precious milliwatts are actually going to the antenna and being used for communications.

Realize though that even with a good match, things are still mismatched between the ATU and the antenna. Be sure to use _good_ coax here - you don’t want to lose those precious milliwatts warming the coax. In other words, at QRP, everything matters, so you have to do everything you can to make the system works properly and folks can actually hear you.

73!

Jack B, W6FB

On Dec 12, 2013, at 7:29 PM, Arno Dienhart <adienhart at gmail.com> wrote:

> Thank you, Don and Jack, that makes sense.
> 
> 
> 
> To explain a bit more, I only operate portable, so my antenna situation is
> practically never the same and I need to tune anew. For my wire antennas I
> use the ATU. If I use the magloop, I bypass the ATU and use the TUNE
> function. That is where I reduced power to .8W.
> 
> 
> 
> After reading your posts, next time I will tune again with .8W and then
> increase tuning power to 3 and compare the SWR. If I did that for enough
> different bands and frequencies, with no discernable difference, I guess I
> would be safe to keep it at low power from then on, right?
> 
> 
> 
> 73 de Arno K7RNO
> 
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