[Premium-Rx] RA6778C AC power switch

[Ben Dover]

I received the following response...



>> Hi all. Ben, you`re frightening me! Of course, when I cleaned up my
receiver
after buying it, I didn`t see this as a problem. I suppose that we all
figure that the engineers know it all and trust their work..

But my friend Clem, VE2BIA, had to change the switch on his 6778 because it
was shorted. He even bought a new power supply for it.
So, I suppose I`ll have to do what I usually do when I use these small
switches : I use both sides of the switch for the live side of AC, and leave
the other side unswitched.

Works fine with polarized AC receptacles.

Thanks for waking me up!

73, de Gilles, VE2AMN <<


Hello Gilles.

Yes, I too tend to rely on the judgement of the design engineers, but being
in the field myself I can tell you from experience that we ALL goof now and 
then. 

The switch is probably adequate for the intended purpose, but hams are NOT the
intended purpose!

I'm reminded of something I read in Robert Serling's book on airline crashes,
THE PROBABLE CAUSE. The Douglas DC-3 is an OLD airplane, and the design is as 
reliable as the come. There was a crash that happened which was traced to a
seemingly insignificant design flaw...   FORTY YEARS after the airplane went
into service!

While this failure was spectacular (and smelly), it wasn't very serious, but
under some circumstances it COULD be, depending on the failure mode of the
switch. 

It's just something that we should be aware of with this radio...   and from 
your friend Clem's experience, my incident apparently isn't unique.


73's,

Tom, W9LBB