Good ARRL article on tuning t-network tuners
http://www.arrl.org/files/file/Technology/tis/info/pdf/9501046.pdf
I was going to say, based on my limited experience, than you shouldn't sweat
the
L vs C choice, and just aim for a 1:1 swr
My thinking: if you're losing at most 1 db in the tuner, your feedline and
probably balun losses and ?? other losses dominate over that.
But Figure 3 was interesting in the article. The min-max curves show the
range
of loss matching into a 10 ohm load...80M showing a >2db loss.
Now back to MFJ bashing.
I used a Palstar at-1500cv in the past, and went back and read up on it. Even
Palstar reduced their mx power recommendation when feeding low impedances.
So: if MFJ failed at the design job, the real question is: how much power is a
"good" tuner supposed to be able to dissipate without catching fire?
That ARRL article shows a case with 40% losses in the tuner.
Is the only good tuner one that can dissipate 600 watts?
With a fire, I'm assuming we're talking about coil dissipation and not
capacitor
arcing.
Rather than just bashing vendors, it would be nice if people complained more
precisely: i.e. a tuner costing XYZ should be able to tune ABC with DEF watts.
Then we could debate if it's possible to achieve those goals for that cost. If
so, is the argument that MFJ is pocketing obscene profits?
Or: that people don't know what they need?
-kevin
ad6z
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