Kevin Normoyle wrote:
>
> 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?
>
I think that's a general problem in the ham radio equipment world.
There's no "real" objective definition for "handles 1.5kW"... is that
1.5kW into any load? 1.5kW into a matched load? 1.5kW when immersed in
carefully stirred and refrigerated cooling oil?
And that's not even considering the usual implied duty cycle (e.g. 1.5
kW PEP on SSB is somewhat different from a 20 minute bulletin
transmission on RTTY).
In the commercial world, one typically sees ratings with a specified
mismatch (e.g. 2:1 VSWR) and the implication is that this is at any
phase angle.
ARRL has done a bit towards testing under somewhat standardized
conditions, but more from a "what's the loss under some not too
difficult to setup tests" standpoint.
And, various online ham writers have done some analysis (and testing) on
some moderately common scenarios.
There's also an enormous amount of repeating in one form or another
guidance from the books by Terman and LaPorte.
What I'd like to see is some work looking at real components used in
real tuners. Just how much dissipation is there in those ceramic caps
used in the LDG or SGC tuners? Ditto for the inductors.
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