> output on the other. Frank says that the C1 and C7
capacitors are sized to
> act as voltage dividers to match the resonators to 50
ohms. I'd like to
> change either C1 or C7 to match 75 ohms so I can use RG-6
from the antenna
> and RG 58 to the radio. Can anyone tell me what size to
make either C1 or
> C7 on the 80 and 160 meter filters to match 75 ohms.
Jim and all,
Just a reminder, most receivers I've measured are nowhere
near 50 ohms on the input for optimum sensitivity. If the
receiver is not 50 ohms it's a waste of time going through a
lot of work to gain less than 1dB for matching the filter.
I'd just do a straight 65 ohm filter design, since that is
centered on the 30-130 ohm range I've measured.
Also, DX Engineering sells splitters. They already have F
connectors for CATV cables. They will handle a fair amount
of power without overload, and I've had good luck with them
on lightning.
73 Tom
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