AWA Capacitor DC Leakage Tester Project

AWA PCB #4 is available for purchase in the AWA On-Line Store here.  A parts list and a YouTube video are available to assist with the creation of your version of this useful piece of test equipment.

Below is one user’s story regarding his use of the AWA Capacitor DC Leakage Tester PCB.  The project below is the information and photographs provided by Gerry Bertrand, the project’s implementation creator.

My DC Leakage Tester

Gerry Bertrand

“I live in the Pacific Northwest with my dear wife of almost 40 years and our wonderful Smooth Fox Terrier. My wife says she finds me handy.

My career has been in the construction industry, which I originally thought would steer toward Architectural design. Along the way I completed Commercial Pilot training but ended up becoming a Registered Building Official for local government. So a lot of training and exams but no formal electronics training.

Electronics has been an interest and hobby since I was a kid. It started with a Crystal Radio Kit around 1970, then the Electronics project kits. When I was 12 our postman gave me a box of broken radios to tinker with. That was the beginning of trying to figure out why things stop working. Of course, broken or loose wires, and failed solder joints are the most common failures but next, I find, is capacitor failures.

My other hobbies include RC Model building and flying. Also, the last several years is 3D Modelling and printing. All of these interests come together for a project like this.

I learned of the Antique Wireless Association DC Leakage Tester from my subscription to w2aew, and realized that it would be a great addition to my collection of test equipment.

The Project

Years ago, I had made an ESR tester from the Dick Smith kit. It has been a useful tool for finding capacitor failures. The DC Leakage tester will allow quick and easy testing of capacitors that I didn’t tend to take the time to perform in the past.

I could have designed the enclosure to be much smaller but I wanted it to have a substantial vintage test equipment look. I took inspiration from vintage equipment in my collection. The knob is an exact scale copy of the one on my Variac. The dial was also inspired by it.

The Enclosure

The enclosure is fully metal and grounded as was suggested. The printed side panels incorporate the Ziggurat pattern common in 1930’s American Art Deco style architecture and products. The almond/cream and red is a vintage colour combination that has always appealed to me.

I used Alan’s, (w2aew) advice for placement of the switches and binding posts. Also, for the interior layout and neatness of the wiring.  (Alan’s YouTube video is on the AWA YouTube Channel below.)

I find it useful to have a dial that is relatively accurately calibrated to the voltage output. It allows dialing in to the rated voltage output even though it may take a considerable time to reach that voltage reading across the capacitor, or, it may never reach the rated voltage for a faulty capacitor.

I have already used it to confirm a leaky capacitor that was biasing a JFET to always on, grounding the signal path on an amplifier. On another repair project it was able to confirm leaky filter capacitors. It has also been useful to check capacitors in my parts box and confirm they are still at factory specifications before installing into a project.”

3D Pinter Illustrations

(Below are two of Gerry’s 3D printing efforts. Note photo to right is a bracket made using a 3D printer. )

(If you are interested in the information with respect to the 3D printer files used by Gerry, go here: https://www.prusaprinters.org/prints/150215-capacitor-dc-leakage-tester-enclosure )