Jim Reid wrote:
>
> At 09:27 PM 6/6/97 -0400, L. B. Cebik wrote:
>
> >Henry,
> >
> >Unless you are using a matched 450-ohm load to 450-ohm lead, the impedance
> >bumps created by relay spacing will be in almost all instances meaningless
> >and minor, with no consequences for efficiency/loss of the power transfer.
> >
> >
> >Also, be sure that the relays can handle the high humidity that will
> >inevitably be present in the remote box. Corrosion does not require
> >direct contact with rain drops.
>
> Loyd Colvin, in his 8/56 QST article, suggests leaving a small
> voltage on the relay coils. This to provide a bit of heat to
> drive the moisutre away. Wonder if it really works, I will try
> with my set up. Plan to use a Radio Shack enclosure for the
> relays/450 ohm lead/V-beam wire connection. Guess will use a
> metal box rather than the plasic ones. Must find some feed-thrus
> to mount/terminate wires.
>
> 73, Jim, KH7M
>
> --
> Jim, some of the commercial relay boxes claim the include a heating element
> to reduce moisture build up. When opened up the heater is a 10 watt wire
> round resistor.
73, Larry L.
wa0etc
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