[Elecraft] Solder Question...

Wed May 28 18:52:00 2003

One more comment on the eutectic solder thread...

From a practical standpoint eutectic 63/37 solder is the one that wets the
leads and pads the easiest and the best and is therefore is best for pin in
hole assembly projects like the K1/K2.

60/40 alloy and 2% silver are two different animals.  60/40 is just "poor
man's" eutectic.  That is, something close to 63/37 that the manufacturer's
process is too sloppy to hold to +or- 1%.

We all understand xx/yy means xx% Sn, i.e. tin and yy% Pb, i.e. lead.
Right?

The 2% silver solder is NOT used for higher conductivity.  The 2% won't make
any significant difference especially at RF when skin effect has the current
flowing on the surface of the conductors.  It is usually used because it is
mechanically stronger, that is, it has higher tensile strength than eutectic
solder.  It is also used in some applications (especially where they have a
solder "hierarchy") for it's higher melting point.  Why do they use it high
power amplifiers?  Either they need the extra strength in the joints or
maybe they need the higher melting point.  I have heard of contesters who
caused KW amplifiers to fail by running 1.5 KW RTTY and melting the solder
on the coil and bandswitch connections.

Very 73,
Dick  W5TA

----- Original Message ----- 
From: "Trevor Jacobs" <[email protected]>
To: "Elecraft Mailing List" <[email protected]>
Sent: Wednesday, May 28, 2003 2:28 AM
Subject: [Elecraft] Solder Question...

> Hey Gang,
>
> I've always used 60/40 alloy solder (or 2% Silver for SMT) , but was
> wondering about the 63/37 alloy? Was wondering what the purpose of the
> different alloys was, other than the melting point (190 C for 60/40 and
> 183 C for 63/37). Is one more preferable for rework?
>
> 73's Trev KG6CYN
> http://www.qsl.net/kg6cyn
>