[Elecraft] K3 just goes off - SOLVED

[Rick Bates]

Apparently, based on the input here, I'm doing it all wrong by crimp and
solder.  But since I started that, I've not had a failure (back when Molex
was king).  Most times the actual connection is secured from motion (not
vibration) while the tails are allowed to move, if needed.  Yes, I use the
proper crimp tool for the connector, but I doubt it is certified.

 

Rick NHC

 

-----Original Message-----
From: Fred Townsend 

 

Rick I use Teflon wire for my battery leads. Teflon wire is silver plated.

The Anderson power poles are silver plated too. While I can not quote

chapter and verse most NASA applications require crimp (with certified

crimper). There are at least two reasons. Solder wets and runs within silver

braid very quickly so the solder runs into the insulated part of the wire

and causes brittle fractures inside the insulation. Also the solder and flux

can get into the power pole contact area and increase contact resistance.

Flux has been known to flow out of solder connections years after

installation. The flux flows when the contact heats. The two effects have

been known to cause thermal runaway. Yes crimp is better than solder

especially for high power DC. 

BTW most silver bearing solders the most common being Sn96Ag4 (not to be

confused with silver solder) carry at most 4% silver. That doesn't offset

the other 96% being a poorer conductor than copper.

73, Fred, AE6QL.