[TowerTalk] Switching 450 ohm twinlead?

[Rick Mainhart]

On Fri, 6 Jun 1997 10:53:23 PST henrypol2@juno.com (Henry A Pollock)
writes:
>Re all the recent posts about the RCS8V coax switch.  How is the best 
>way to remotely switch 450 ohm twinlead? 

For the ultimate in power handling capabilities, I'd go with three-phase
contactors (sometimes called starters). These puppies come in many
flavors and sizes, but unless you're into hot-switching (which I wouldn't
do), you don't need the arc-quenching 550 amp versions.

Coil voltages range from 12 to 480 Volts ... and auxiliary contacts to
prevent keying into an open.

Prices vary depending on the source, but for a 7.5 kW unit figure on
$50-75.

As for impedance bumps at 450 ohms ... I don't think I'd worry much about
that. Same thing with putting everything into a non-conductive box ...
probably more expense than required.

If the price is too high, look for starter relays and/or auxiliary
lighting relays at your local automotive parts house. Calculate your
maximum current, and provide a bit of margin.

73,

Rick, WB3EXR


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