For technicians in the consumer goods/home entertainment repair industry,
the present situation can be defined as BOHICA.

Manufacturers haven't been soldering consumer goods properly for decades,
and I agree with your summary, that with lead-free, it's going to get much
worse.
I'm sure some are thinking: Opportunity. No, not when the owner can buy a
new one for less than a repair job.

Did anyone own a RCA Thomson(?) TV of the 90s that didn't fail within two
years? The CTC77 type, for a few series with bad tuner shield soldering,
where the shield was used for needed circuit continuity.

Even so, much earlier, many types of electronic gear failures were a result
of soldering faults/failures.

There was a SER post years ago titled something like; why can't
manufacturers solder?

Apparently the company accountants were in charge of the speed control of
the track feed as the boards passed thru the solder wave bath, it seems.
At double speed, they could potentially save tens-of-thousands of dollars in
solder purchasing costs per year.. or something similar.

As any techs with some years of experience have seen countless times, larger
components that can dissipate more heat during the soldering phase of
manufacturing rarely get soldered properly.

Automation in board fabrication was a huge advancement in electronic
manufacturing, but that wasn't satisfactory for the
accountant/profits-driven manufacturing model.

The Chinese have taken nearly every manufacturing process to a whole 'nother
lower level, even before lead-free.
It's disgusting that the American and other countries' consumers keep buying
this shiney new worthless crap, with much of it being put out for trash
pickup within a year.. year after year (and paying to have it hauled away).
Undoubtedly, many career positions available in waste management.

Get used to the likelyhood that any vacant land will become landfill pits..
who knows, maybe even our national parks.
When the groundwater aquafers are nearly totally fuctup, a fleet of space
shuttles can start hauling it away.
Where's the koolaid line form? I wanna be at the front of the line (if I
even last much longer).

All of this low grade crap manufactured today should be imported only with a
Return to Sender Free agreement. Let them dispose of all this worthless
crap.. and I'm fairly sure they would, and sell it again as recycled, but
fresh, new products.

I try to buy older stuff that was manufactured to a slightly higher level of
quality, which may at least be repairable. Anymore, I only repair my own
stuff, or a limited number of items that I want to, for a few close friends.

What's taken place, I think, which I suspect was intentionally forced upon
most of us, is that manufacturers wanted to lower everyone's expectations of
quality.
With that accomplished, all they need to do is make sure there are shelves
full of new crap to replace the old crap with.

How many times has someone been heard saying; I'll never buy that brand
again, next time I'll buy a (different brand)?
Catch 22.. it's nearly all the same, in retail stores, anyway. Before they
know it, they choose another product from the same brand name they started
with.. and round 'n round it goes.

--
Cheers,
WB
..............


"Arfa Daily" wrote in message
...
The first is the Warrior amp that I posted on here about, looking for
schematics. None were found, and as expected, the importer ignored my
pleas, so I decided I would spend a half hour on it 'blind'.

It turned out to not be too difficult to get the main PCB out, complete
with heatsinks and back panel. The wiring was long enough to allow the
board to be turned over, without having to disconnect everything. The
fault was that one of the two identical output stages was behaving as a
pretty good half wave rectifier, but only with a load connected. With no
load, an applied sine wave was perfectly symmetrical at the output
terminals, and of similar size to the good channel. With a load connected,
the negative excursions disappeared almost totally. Nothing was burning,
and the the output protect didn't even fire until the wick was turned well
up, which led me to believe that the problem may well be back in the
driver stages or earlier. As there are two identical amps, I figured that
I would start with a few comparitive resistance checks between channels.
Quickly, I found that at the base pin of one of the driver transistors, I
had a reading of 3k or so on the good channel, but open circuit at the
same point on the bad channel. I followed the print back and took another
reading and Lo! - 3k ...

So I went back to the transistor leg - open, but at the joint, 3k. I tell
you, I examined that joint with the strongest light and magnifier that I
have, but you could not see a problem with it. However, as soon as it was
resoldered, 3k on the leg as well, and the amp then worked normally. This
is the problem with lead free. You can no longer spot bad joints by eye,
and they don't behave like conventional bad joints any more.

The second one was a Vox combo. This one was reported as "goes off after a
while - tap top to get it back". It actually ran for about 2 hours, during
which time I thrashed the output stage so hard you couldn't touch the
heatsink, and periodically knocked seven bells out of it with the butt end
of a large philips screwdy. At no time did it show any signs of
intermittency. I was actually on the phone to the store that it came to me
from, to check if they knew the owner, and whether he was savvy, or a
numpty, when it went off. Just like that. No provocation. You could then
lightly tap the top of the chassis just about anywhere, and it would come
and go at will. So easy was it to make it do it, you would have thought
that the joint causing it would have been really easily spotted. I twisted
and wiggled everything I could, but nothing made it do it, but still the
lightest tap, and there it went.

Eventually, after a frustrating session of blanket resoldering that did no
good at all, I came to a power resistor standing up off the board. It was
a component that I had previously twisted. This time I pulled it, and one
leg just came right out of the board. The joint looked perfectly normal -
for lead-free that is - but it had not whetted the resistor leg at all.
How the hell could that take two hours to go bad, not be responsive at all
before that time, and then when it has gone bad, not respond to twisting,
but be so tap sensitive that you could make it come and go with a feather?
I HATE lead-free with a passion.

If it ever finds its way into avionics, be afraid, be VERY afraid ...

Arfa