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Eeyore Eeyore is offline
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Default So what's the truth about lead-free solder ?



Arfa Daily wrote:

"Eeyore" wrote
Spurious Response wrote:
Eeyore wrote:
"Leeper" wrote:

t is really application and chip package specific,

Bull****. Lead based solder alloys are superior in damn near all
electronic realms, and there is no configuration where they would not
be other than high end commercial and military applications, and they
certainly do not include Tin.

Whilst I don't disagree with you, where's the hard comparative data ?

Considering the fact that we have 5 decade old circuit cards still
operating perfectly, and that we already know what alloys containing Tin
which is not bound by Lead do over time and temperature cycling, I do not
think that precise numerical analysis is even needed on such a profoundly
lopsided issue.


Whilst I agree with you, bureacrats tend not to be very receptive to
anecdotal comment. And make no mistake, the bureacrats are the ones in

control of
this.



I have just this minute finished repairing a Panasonic DAB / FM radio which
was dying as soon as it was switched on, with a "F76 Pdet" error in the
display. I took this to be "power detect", which seemed reasonable, given
the symptoms. When I took the main board out to have a look at the
underside, I found the power supply section riddled with poor and
'cracked-right-round' lead-free solder joints ( the board actually has
"PbF" silk-screened on it ). The poor joints were particularly well defined
on the main free-air cooled regulator transistor, which is obviously subject
to thermal cycling.

I reworked all the joints with lead-free, as that is what the RoHS
legislation legally charges me to do as a commercial repair outfit, but boy,
the temptation was strong to just reach for the leaded solder, and do the
job 'properly' ...


Have you considered documenting this stuff ? With a scan or a pic for example ?

What do you tell the customer ? That Greenpeace is to blame ?

Graham