[Elecraft] 1SV149 mounting question

[Rod N0RC]

Thanks all who have responded so far.

Some have mentioned that the solder mask will protect things. Not
likely, the solder mask does not cover the pads on top of the PCB. See
figure below.



           #####
           #   #  <- diode body
           #####     U = lead trimmed flush to diode body
           | U |
      ____=|=_=|=____ "__" = Solder mask, "===" = solder pad
      *****|***|***** <- PCB
           |   | <--diode leads (2)

If the mechanical tolerances are not exact and proper the trimmed lead
"U" may bridge the gap between the pads "=". The pad edges do no
appear to be protected by solder mask.

I think for personal piece of mind I'll lift the part off the board
such that the trimmed lead is off the board a few thousands of an
inch.

NOT DON'T ALL GET CONCERNED THAT THIS IS A BIG PROBLEM, I'M SURE
THINGS ARE FINE. I tested each diode with a ohmmeter, no shorts were
found with the diodes mounted per Elecraft instructions. I am
personally looking for an EXTRA measure of reliability. (I once worked
as a manufacturing engineer for commercial and military avionics
equipment. It is indigenous for me to worry about such small detail
;-)

73, Rod N0RC
Ft Collins, CO




----- Original Message -----
From: "Rod N0RC" <rod@n0rc.com>
To: "Elecraft-list" <elecraft@mailman.qth.net>
Sent: Sunday, March 24, 2002 12:46 PM
Subject: [Elecraft] 1SV149 mounting question


> Folks,
>
> The K2 manual states:
>
> "Install type 1SV149 diodes .... Keep them flat against the PC
> board, with no excess lead length."
>
> I'm concerned about the center lead of the diode, cut flush to
> the diode body, forming a bridge bridge between the PCB pads for
> the others lead.
>