Kevin McMurtrie

In article <_JednRlGgsfQQ0bYnZ2dnUVZ8sCvnZ2d@bt.com>,
"Lez Pawl" <Lez@Pawlbtinternet.com> wrote:

> "John & Ninetta" <jsuljak@sentex.net> wrote in message
> news:qu2dnXHyGpt0W0bYnZ2dnUVZ_vupnZ2d@sentex.net.. .
> > >
> >> crack in a circuit board track.....when it contracts the track parts.
> >>
> >
> > Would this circuit board track be in the radio itself, or elsewhere?
> >
>
> most probably in the radio...........may also be a soldered (dry) joint
> somewhere in radio.
>
> I believe some manufacturers are using 'green solder' ie lead free and this
> could be the problem.
>
> It is rather odd that when delving deep into electronics goods
> specifications many actually state, only operate at 0-30C.................

Often it's caused by bolting power semiconductors to heat sink fins on
the chassis. Vibration and thermal stress eventually cracks the solder
or even the circuit board. Better designs use a spring clip so that the
component can slide under high stress.