[Elecraft] K2 #3338 problem solved

[Don Brown]

Hi

I have found a way to help prevent this type of problem when building a
circuit board. I install a series of resistors or capacitors. Then solder
all of the leads. At this point a lot of people will hold the board over the
trash can and clip the leads. This is how missed solder joints happen. I
clip the leads one at a time looking at each one as I clip it to make sure
they are soldered. If I find one I missed then I continue clipping the rest
and go back and correct the un-soldered joints. The action of clipping each
lead forces you to look at each joint so the missed ones are more visible.

Don Brown
KD5NDB


----- Original Message -----
From: "Steve Ratzlaff" <steveratz@eoni.com>
To: <elecraft@mailman.qth.net>
Sent: Wednesday, March 19, 2003 9:49 PM
Subject: [Elecraft] K2 #3338 problem solved


> Hi,
> "It's the soldering, dummy". My intermittent receive problem on all
> bands was due to an unsoldered D3 anode, in the T/R switching line, in
> the antenna/filters RF section path. This diode is right at the rear of
> the board, where I claimed I'd made an extra inspection and reheated all
> those connections. So much for my claims. I didn't even find it by
> inspection either. I had a signal connected to the antenna connector and
> was pondering the problem, when I idly touched the top rear of the
> board, near D2. Just a light touch caused the intermittent to happen.
> Since D2 was soldered on the bottom, and the top had a nice shiny look I
> turned the radio over to inspect D2--it was soldered, but right next to
> it was D3's unsoldered shiny pad staring at me, with its lead cut flush
> with the pad. Another soldered pad was right next to it--I guess my eye
> kept seeing the soldered connection and refused to see D3's shiny
> unsoldered pad.
> Memo to self--"it's the soldering, dummy"--slow down and inspect the
> pads one more time, then if necessary, one more time until you spot it.
>
> Thanks to those who gave very helpful suggestions, but the solution was
> as simple as could be--check the soldering, even when you think you've
> already checked it! Gary Surrency was the first help reply I received,
> and his one and only tip--it's the soldering dummy (but he didn't phrase
> it that bluntly, he was kind). He was right.
>
> Steve