Flux Your Braid

Grand knows his stuff – thank you, Sir!

More flux did the trick.

If you’ve been following the action here, you’ll know that I botched my first attempt with the integrated circuit you see here as “The Problem”. The two pins in the lower right corner of the 1/8" square integrated circuit are shorted together and I couldn’t remove the excess solder. I figured the part was a goner.

But Grand who commented on my earlier post said I just needed more flux and, in particular, to flux the braid that would be used to suck away the excess solder. And voila, it worked, just as he said!

Everyone repeat after me:

The part cleaned up nicely and, with the aid of a much smaller tip on the soldering iron, it’s now in place on the board. (It looks icky in the final photo because I had not cleaned away the excess flux yet.) After attaching it to the board, I used my ohmmeter to check for shorts or breaks. From the schematic, I figured out another part each pin was supposed to connect to and then I verified from that part to the knee of this integrated circuit. I also checked adjacent pins for shorts but everything seems to be exactly right.

Hurray!

What remains to be seen, of course, is if all the soldering, unsoldering, failed attempts at clean up, success at clean up and then re-soldering onto the board, has killed what’s inside. That’s a lot of heat. But there’s no way to test that now so I won’t know until the transmitter that uses this board is nearly complete. At the rate I’ve been progressing, that is weeks away. If the part is toast, I’ll have a couple of spares and now that Grand has shared the secret – flux, flux and more flux – replacing it won’t be a problem.

Milestone #1 on this project is now complete.

There’s another circuit board to populate, and then I’ll be cutting, drilling and painting the box, and finally attaching the controls and LCD and then interconnecting everything. There are many hours to go in this project but finishing the first board is a good start, a very good start.

And again, my thanks to Grand for his suggestions. They are very much appreciated!