[Elecraft] 2-sided PCB component soldering?

[Bill W5WVO]

Fred (FL) wrote:

> The "hole" and Elecraft's 2-sided PCB's always puzzled
> me a bit - as I was never sure if there were pads,
> plated-thru hole, and lower pads - every time.  In
> other words when I soldered a component on the top
> side of the RF Board - and got a great solder flow -
> was I supposed to look to see if there was a pad
> and "great flow" on the bottom side too?
>
> OR DOES THE PLATED-THRU HOLE, TAKE CARE OF THAT?

Very early in the PCB days, double-sided PCBs did not have plated-through
component holes, so it was necessary to solder both sides of each component
connection. PCBs have had plated-through holes for a LONG time, so this is
no longer an issue. Nevertheless, insufficient heat and/or application time
can cause the solder not to flow smoothly through the plated hole and create
a good fillet on the other side of the board. This should ALWAYS happen,
because otherwise you're depending on the integrity of the plated-through
hole to conduct current between sides (or layers, in multilayer boards).
Murphy sez this ain't a good idea!

I always inspect all solder joints on both sides of the board to make sure
they look right.

Bill W5WVO