[Elecraft] toroid leads

[Don Wilhelm]

Terry,

Congratulations on your success, but not everyone is so fortunate, 
witness to that fact is the number of toroid leads that I have to 
re-strip and tin in the radios that I repair.  What you are doing is 
tinning the leads in-place, nothing wrong with that but one must observe 
carefully to assure that the solder actually does flow onto the lead and 
not just stick to it in a solder ball.

Just a note on the use of silver bearing solder, it is not necessary for 
thru-plated holes, and it is more difficult to remove should component 
removal be required or desirable.  I do use it with good success for SMD 
components, where its wetting action is really a good asset.

A good solder with mildly activated flux wets and flows nearly the same 
as the silver bearing - I particularly like the 63/37 alloy because 
chances of a cold solder joint resulting from movement while cooling is 
very slim indeed with no plastic state to contend with (it is either 
molten or solid - nothing in between).

If you continue to be careful, you may not have to thaw that crowmeat.

73,
Don W3FPR

Terry Wilkinson wrote:
> Just a quick comment on stripping/tinning of toroid leads...
> 
> I've built the Norcal40A, K1, and K2, all without tinning the 
> toroid leads (I do make certain that the leads are scrupulously 
> free of enamel). All three rigs work great. Maybe the reason I 
> get away without tinning the leads is that I use silver solder, 
> which seems to be "wetter" than regular solder, and I take care 
> to ensure that the solder has obviously flowed onto the leads 
> and pads before moving on. My use of silver solder was on the 
> recommendation of the fellow from whom I purchased the 
> Norcal40A.
> 
> However, I admit to a bit of fear and trepidation, after reading 
> Don's warning about the consequences of not properly tinning 
> the toroid leads! I've got some crowmeat in the freezer, just in 
> case I have to eat some!
> 
> Terry - W1BPJ