> Was "shocked" to see that the contact was made when
> the EDGE of a thin strip of metal was pressed down
> against the flat surface of another strip. It was at such
> a contact I had experienced an arc or burning do to
> high swr, I guess. Anyway, the switch became NG.
Most of these indoor manual switches are imports, and I suspect
many are from the same manufacturer.
The MFJ switches I looked at had a lightning protector with too low
a rating. With a "typical" 1500 watt amp into a 2:1 SWR the
lightning protection pills would sometimes conduct.
I am NOT a fan of gas tubes for lightning protection at HF with high
power. They usually cause more damage than they prevent, but
some people insist on using them.
Also the die cast housing had supports that were about 50
thousands of an inch too high. This caused the small springs that
push up on the board that forms the stationary contacts to be at
the end of travel, and not apply any tension to the contacts.
Once the lightning pill voltage was increased and the housing were
done properly that switch became very reliable.
You might look carefully at yours and see if the stationary contact
board floats on four little springs. Maybe it has a mechanical
problem like the units MFJ imported had.
I now use an RCS8V for my indoor (and outdoor) high-power
switching.
73, Tom W8JI
W8JI@contesting.com
________________________________________________________________________
Where do you get ICE bandpass filters & beverage matching boxes? The
same place that pays for the hosting of this list: The eHam Store.
Order online at http://store.eham.net.
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