Testing for a Good Solder Connections

By John Mastromoro

Soldering If not caught immediately, a solder connection on a circuit board can turn into a real nightmare, especially if using CMOS components with IC sockets. Here is a very simple, inexpensive and positive good solder connection idea.

On an ideal, solid, flat, sturdy surface approximately 5-inches square [acrylic or thin wood panel section] evenly spread across it a double-layered sheet of smoothed-out tin foil.

Place and firmly press down onto the foil the soldered-side of the circuit board with component side up. Use common sense for proper pressure applied to make solder connections with tin foil.

With one lead of an ohm meter [set at Rx1 or Rx10] clipped to the tin foil sheet, touch the other lead to the top-side component connection in test.

If you get a reading, the component is soldered correctly. If not, press somewhat firmer at that point to reassure the connection. If no reading, you have a bad solder point.

I use this simple quick method when using a number of IC sockets and it has paid off, considering it was done before I inserted the ICs.

I hope it helps some hobbyists.

Check out some of John's other Tech Tips

Play-Doh Third Hand
Create a Pin Alignment Tool
Identifying Electronic Components

If you have an electronics tech tip you'd like to share, please email [email protected]
I was using the great hint about testing solder joints with aluminum foil and found success doing it on a solid surface but there were a few times one solder joint was slightly larger than one very nearby, probably due to the amount of solder used or size of the lead going through or resulting length of lead after being trimmed. I could test it "in the air" and it was fine but on a solid surface I couldn't get continuity.

I solved the problem by putting some soft foam underneath the aluminum foil and things worked just fine. The whole process even went faster because I didn't have to push hard to make contact.

I was able to quickly "rescue" 3 circuit boards worth hundreds of dollars that had been set aside years ago as "puzzles" waiting to be solved. Now I look forward to solving other circuit board puzzles in the future. Priceless!!!

--Gary Foxe