On a sunny day (Fri, 22 Sep 2006 18:43:01 -0400) it happened
wrote in :


Many connectors are these days just pressed on (ethernet, phone, etc) and just
as or more reliable then soldered connectors.

Over thirty years?

Possibly

You can slow down but you can't stop galvanic action, oxidation or
migration of foreign materials.

When the same materials are used, say copper clamped in copper (as in
the cable), and gold touching gold (as in the connector surfaces), and
if no motion (any connector is limited by a number of matings), there
will be little 'migration', no galvanic action.
Oxidation may happen and does any time with copper, and the same with solder!

If you look a bit at the practical side, I had a TV repair shop for many years.
The MOST frequent fault was, in TVs with connectors for the modules, that
the connectors pins became un-soldered in the main PCB, due to thermal cycling.
The copper pin expands, it pushes the solder outwards around it, then it contracts,
the solder stays where it is.
The same happens with other components that get hot, like coils, transformers,
transistors, and if you can still remember these, ALWAYS with tube sockets soldered
in PCBs.
I have made good money repairing TVs by just re-soldering the boards.

People who ever worked with wire-wrap will know that wire-wrap is more
reliable then soldering, and I KNOW soldering.

It is exactly the fact that solder - copper or whatever layer that can cause
problems.

But that does not mean you should not solder.

When I learned soldering, you had to put the wire through the hole, wrap it around the
pin or whatever, and _then_ solder it.
To prevent shearing of.

You like soldering, I will show you something, now I have to go to the attic
to find some board, be right back,
OK, have it, now some pictures:
Z80 processor board, component side:
ftp://panteltje.com/pub/s/z80_board.jpg
same, _wiring_ side:
ftp://panteltje.com/pub/s/wiring1.jpg
ftp://panteltje.com/pub/s/wiring2.jpg

To give you an idea, it is about 544 connections, all fly-by-wire so to speak,
none are marked, this board still works after what is it? 20 years?
Has been upgraded for some more newer chips 10 years ago or so.
Was a computer prototype, build in 3 evenings.

You will note it collected dust, has been dropped, thrown around, abused.
and still all wires are intact, 544 solder connections by hand with multi-
strand cable, you need 1) good vision, 2) steady hand, 3) good soldering iron,
4) absolute memory what you did already route.
In this time, when I did this sort of thing, there were no user affordable
PCB CAD programs, let alone user affordable multi-layers PCBs.

So, anyways, I think I know about soldering, like it even, so I am not biased
if I say it is not perfect.