[Amps] current threads about silver solder and resoldering

[Steve]

For hi-rel and space applications double soldering is done where there's 
gold in the mix. Above a certain concentration gold and solder can go 
brittle with time and/or heat - I've seen it in old solid state amps 
where the joints on the leads go intermittent. Often the gold and 
underplating completely detach from the lead and there's no way to 
remake the joint.

Steve

> 2.  Years ago, I worked as an electronic tech, and learned that some assembly
> contracts required first soldering a joint, then sucking and wicking all the
> solder out of the connection, then resoldering it.  I understood informally
> (i.e., not confirmed) that this was the requirement and standard for NASA
> contracts, because of the constant vibration in their applications.  This
> procedure makes for much greater reliability.