> However, would it still not be possible to use the same
> inductor between the tube and tuning cap on a couple of
> adjacent bands, e.g.. 17/15, 12/10, etc.? That might get
> the requirement down if the input used a more complex
> filters.
I just went through that exercise with a 3CX1200Z7. I can leave the
inductor in on 10 meters down, but things aren't quite the way I like
them. Harmonic suppression is just at the edge of limits on 15
meters, and it's possible to tune the PA to not meet requirements.
The problem on the input is when I get enough Q to be a good
lowpass and not drive harmonics back into the radio, the bandwidth
is too narrow to cover adjacent bands well. Perhaps a double L
network or two section pi would work.
> As an alternative, would it not be possible to use a
> single inductor appropriate for 6 or 10 and leave it in
> place on all bands since it becomes progressively "smaller"
> as one moves down in frequency?
Six meters is out of the question, it would have to be switched to
not mess Q up on ten.
I'm settling on two switch ideas.
Using a modified JV-9000 as a switch for all but the most
demanding contacts, and using a cam (per the Henry-does-it-this-
way suggestion) to move HV contacts for the few critical points...or
buying the RSC switch components without contacts on the critical
wafer and having contacts made with larger air gaps between the
rotor and stator for that one section.
73, Tom W8JI
w8ji@contesting.com
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