spamtrap1888 wrote in message
...
On Apr 5, 7:41 am, "N_Cook" wrote:
Probably the worst bit of "soldering" i've ever seen on Citronic Digi 16P
mixer amp, Made in China it says on the rear.
An intermittant fault with one channel speaker, the wires 2.7mm diameter
over the insulation, 1.5mm or so core, the 4 wires go to a rear board for
speakons and 1/4 inch outlets. Each wire is stripped neatly , leaving some
whitish thin coating over the copper core wires that probably holds the
filaments together until solder temperature melts it . Pushed through the
large holes in the solder pads and "soldered" on the blank side of the
board
with little blobs of solder relying on melting of the board composite to
hold in place, and unmelted coating plainly visible on the other side. I
assume the holes are plated through or there would be no electrical
connection possible. The assembler must have passed the wires wrong way
through and soldered the wrong side.

So, no solder pads on the back? I thought a plated-thru hole had to
have copper on both sides. Further, I would think that even the
simplest board would be asymmetrical. Is the phasing messed up? Left
and right channels switched?

+++++=

Does the plate-through process need metal either side? This board has metal
on one side only , I was only assuming it must be plated through. Set up as
A and B so difficult to say but A side amp corresponds to A side outlets but
then L & R are often swapped as far as "viewing" from the front.