> I'm putting up a multi-band (20,17,15,12,10 & 6) quad antenna (2 el Gem
> spider quad) and will be feeding each band wire with a separate feedline
> through a switchbox (Ameritron). Each feedline between the switch & antenna
> will be a 1/4 wave stub of RG62 or RG11 cut to length. At each feedpoint, I
> intend to put a ferrite bead balun on the coax to help minimize wire
> interaction.
>
> While I think the right bead mix is #77 (or maybe #43) to suppress 10 - 50
> MHz, what I don't know is how much impedence do I need and thus, how many
> beads to put on the line. Somewhere along the way, I read that the balun
> impedence should be 5x the load impedence.
>
> If the quad is at 100 - 130 ohms, should I design for 600 ohms of balun
> impedence? Why 5x and is this a valid rule of thumb?
>
> 73's
> Steve KD7NTK
>
>
>
>
_______________________________________________
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