Jon, VE8JJ, wrote: I just want to confirm the assembly instructions: R18 and R19 are basically resistors with value of 0 (zero) ohms. So you solder in a piece of wire for each of them. Then if and when you are ready to install KAF2, you desolder and remove the two wires at R18 and R19.
With my trusty Hakko 936 at the ready, soldering is a joy. Desoldering, on the other hand, is something I can't seem to do even if my life depended on it. I know what conventional wisdom has to say about silver solder, but that's what I am using because it just seems so much easier to solder with. Plus, like writing a math test with a pen, it's a terrific incentive to get things right the first time. The downside is, with my skills, or lack of, if any desoldering has to be done, the patient will surely die. Any thoughts on a "solderless" solution to R18 and R19? ------------------------------------------------------------ Hello Jon: Because R18 and R19 are jumpers, they are easy to remove: just cut them. If you want to clear those pads, you can simply heat the pads while holding the cut jumper and pull *gently*. When the solder melts, it'll slip right out. There's nothing inherently "better" about using silver solder in the K2. It is needed in certain very critical RF applications where very high RF currents are flowing at very high frequencies. For example, in some 900 MHz repeater equipment that I've serviced the manufacturer required that silver solder be used in its power amplifier circuits. Elecraft backed off of suggesting silver solder because it offers no technical or performance advantage and is slightly harder to remove. Still, you shouldn't have any trouble if you use a good quality solder-sucker like Elecraft recommends. Solder wick will work FB too, when done properly. What most ops miss is that you *must* raise the temperature of your iron when using wick. That wick soaks up a lot of heat. I crank up my soldering iron temperature to 800 to 850 degrees F and then use narrow wick and work at the *end* of the wick (keep cutting away the used segments) to minimize the amount copper there to absorb heat from the iron. Done that way, sometimes the wick is faster and easier for me than pulling out the solder-sucker. Board traces get lifted when too much total heat energy is put onto them, not by temperature alone. An iron or wick that is just barely hot enough to work so it must be left in place a l-o-n-g time will do far, far more damage than a hotter iron or wick left on there a short time. By the way, I *never* took a math test using a fountain pen! I was the guy sitting there in a cloud of eraser dust with a pocket full of pencils. You have courage Jon, and I'm sure that your pride in the work and the performance of your K2 will reward you in the end! Ron AC7AC _______________________________________________ Elecraft mailing list Post to: [email protected] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
