[Elecraft] W1 Power Meter and W8FGU Case

[Don Wilhelm]

Bill,

I have not had any problems myself, but some boards "suck away" the heat 
from the soldering iron tip more so than others - and that is true 
whether the boards are RoHS or not.
I routinely use about 750 deg F for soldering and bump it up to 800 deg 
if the board traces are large or there is a large ground plane.
Leaded solder usually works fine with the RoHS boards too.  Just be 
certain to heat the pads adequately - watch for the point when the 
solder flows out onto the pad.  If the solder pads are not adequately 
heated there will be a poor solder connection just waiting until some 
crucial moment to fail.  Murphy strikes at the worst possible moments.

Many, boards that I "repair" are solved by reflowing the solder with a 
hot soldering iron.  There seems to be a tendency among some builders to 
not heat the solder pads.  Whether that stems from old experiences of 
lifting solder pads on poor boards or fear of damaging components, I 
just don't know, but when using a temperature controlled soldering iron 
and applying heat until the solder flows, those fears should be put to 
rest.  Elecraft uses thru-plated holes on the boards and components will 
stand soldering temperatures for short times (usually 6 to 10 seconds), 
so there should not be a fear of damaging components with soldering heat 
applied for 2 to 3 seconds.  On a normal size solder pad, if the solder 
does not flow in 3 seconds, the iron is not hot enough and if it flows 
in less than 2 seconds the iron is too hot.

My other 'rule' is to use a solder thin enough so you can control the 
amount of solder applied easily (.015 to .020 inch diameter) and a 
mildly activated flux so the flux does not create a mess (Kester 285 is 
my opinion of good solder and flux).

73,
Don W3FPR

Bill Miner wrote:
> Hello Elecrafters,
>  
> I just completed assembly of a W1 Power Meter kit.  It seems to work well with good accuracy.  
>  
> For some reason I had a bit of trouble making good solder connections.  This is the first RoHS board that has given me trouble.  It seemed like it took extra amounts of time and heat to make good solder joints. Is there some special solder flux that should be used when using normal lead solder on an RoHS board?
>  
> The W8FGU case is very nice.  Fit and finish were perfect and the installation instructions on his web site are very clear.  I have some experience working with plastics and probably could have made my own case.  However, considering time and the cost of materials a DIY case would probably cost more and might not turn out as nice.  Many thanks to Dave for providing this service. 
>  
> 73,
> Bill - K6WLM
> K2
> KX1 
>   
>