<i>Please don't take this as argumentative, but I disagree with most of
this.</i>
Why am I not suprised?
<i>I've never seen a problem from contact staking, and can't imagine one
occuring. After all, the relay depends on a small contact patch for the
connection with minimal pressure. Staking actually displaces or flows
the
metal and the connection pressures are enormous.</i>
I have, several times. But I am talking well aged hamfest table items
that look appealing.
<i>Soldering will make things worse. It will remove temper from the
material
> and you run the risk of spattering rosen or solder on the contacts</i>
Disagee on all counts. Unless you heat to the point of distorting the
grain structure (AND you must also let it cool slowly) there will be
little or no effect. As far as splatter and rosin, all it takes is a
competent solderer and mineral spirits.
<i>The contact bars are generally berylium copper. I don't think I have
ever
> seen stainless in the hundreds of relays I have looked at.</i>
I was thinking of the ones that looked like polished stainless, not the
obvious berrillium. Just a guess on my part as they required an acid to
tin.
<i>Actually woven braid is the worse possible thing to use. The best
would be
something like thin wide copper foil, and a close second would be flat
parallel strands that are NOT twisted. The worse case situation would be
a
loose-woven conductor. The reason is skin effect.</i>
I suspect that very few of us will worry about that at HF as amp
manufacturers have used braid for decades with no problems.
A bigger concern with some relays would be the non 50-75 Ohm impedence
bump if used in a critical application. Often quite simple to compensate
for and no lab instrumentation required.
<i>I've sampled and tested literally hundreds of relays, and I picked
the
> particular relays used in many products based on hundreds of hours of
> testing. </i>
Not an option for most of us normal folk without a corporate R&D budget.
I suspect those of us would be satisfied knowing how to improve on what
they may pick up for $.50 or have in the junk box.
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Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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