[sdiy] stupid solder

[Ingo Debus]

Grant Richter wrote:
> You may also consider the current flow in the solder joint. If the joint is
> not perfectly formed it may demonstrate a higher resistance. The voltage
> error produced by the added resistance will be I x R. So for a 1 milliamp
> current flow, the voltage difference between say 100 milliohms and 500
> milliohms will only introduce and error voltage in the microvolts.

A few 100 milliohms can be really bad if they are in series with the
connection to ground of a shield of a low level unbalanced audio cable
(like from a tape playback head).

Are "bad" solder joints really just ohmic resistors? Or are they more
complicated, like dc voltage sources, or even noise sources?

Ingo