Dan,
The way a current balun is wired for a 4:1 impedance transformation is
to connect the two secondary in series while the primary is connected in
parallel. There is just no way that I can imagine to re-wire it and
achieve the goal you are seeking.
You may be successful if you use two baluns. Connect the 1:1 balun at
the parallel line feedpoint and use a coax TEE, one side of the TEE goes
to the ANT1 connector, and the other side of the TEE goes to the OUTPUT
side of the 4:1 balun (with its input connected to ANT2). Do not ground
the 4:1 balun except through the coax shield. In this configuration,
the 4:1 element is not really a balun, but is being used as a
transmission line transformer (or as some have called such things, a
"Unun").
If you are using the KPA100, watch for heating of the 1:1 balun when the
4:1 balun is in-line because it would be used at 4 times its design
input impedance, and the max power rating would be reduced.
OK, now, I really don't know how well this will work, but it does have
enough possibility that it may merit the effort of experimenting with
it. Theoretically, it should work.
73,
Don W3FPR
Dan Barker wrote:
> If there is a way to wire up the BL-2 so it's two ratios were exposed on the
> input side, rather than the output side, one could run two coax from the
> Ant1 and Ant2 jacks on their KAT2 to the BL-2 simultaneously. Then, the
> remembered Ant 1/2 choice per band would automagically select the Balun
> ratio.
>
> I've had my K2 (#2456; KAT2, KNB2, KPSK2, K160R) for years, and just ordered
> the BL-2 (to go with my new antenna). I was trying to figure out how to ease
> my ailing memory, but I don't know enough about transformers. I did check
> the KAT2 schematic. The non-selected antenna is open, not terminated.
>
> For those with the skills, but not the schematic, check out
>
http://www.visioncomm.net/images/bl2.jpg>
> Dan Barker
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