[Elecraft] K2 RF board resistance check - RYCOM

[Don Wilhelm]

You have good eyes Andy!!!
Sounds like Wayne and Eric need to pound a bit harder on the board vendor -
the last I heard, Elecraft is paying for a complete 'bed of nails' or
similar test on all boards - which should have picked this up.  I think this
is the 2nd or 3rd report of a similar short over the past couple of months.
Stuff like this happens and fortunately it is not that common.  Sorry it
happened to you.

73,
Don W3FPR

----- Original Message -----

I sent Charles a direct reply but am sending this one to the List.
People, take a look at his shots, and click on the right hand
one to enlarge. That's the top side.

Now look very carefully at the highlighted hole. The bright silver
(tinned) pad looks great, but the green solder mask covers the area
around it. See how there's a bulging "halo" of copper underneath
in the 7:00 - 8:00 position?

Now look carefully at the 1:00 position. It looks like there's a similar
bulge, except this one is big and sure looks like it's touching the
ground area nearby. I bet that's where the short is. I told Charles
to scrape the point of an x-acto knife around the pad.

This photo is a great example of what can crop up occasionally.
I will say (and most would agree) that the Elecraft boards are
great quality and this kind of thing is probably extremely rare.

I built a Ten Tec 30m QRP kit several years ago and had a similar
short, which was not only under the solder mask, but it was under
the silkscreen for the component outline! Troubleshot to the pin
and eventually found it.