ZIF Socket adapter for Peak Electronic DCA75

I realized I need this adapter once I saw the idea posted here https://forum.pedalpcb.com/threads/building-a-jfet-matcher.14193/post-162931

I initially did not bookmark the page and thus I was unable to credit the idea. But I found a tiny photo I saved on my phone when I first saw it – and Google Lens located the topic!

Here is my take:

ZIF Socket adapter for Peak Electronic DCA75 Component Tester

I bought the Peak Electronic DCA75 component tester for its abilities to calculate the Germanium transistors leakage current. However, it is tedious to use. You attach the transistors with hook clips. If you have a lot of transistors to go through, it gets tiring very fast. It is very boring to detach / reattach the hook clips while making sure the leads of the transistors don’t short together (since the hook clip leads are very thick and rather rigid).

This adapter solves the problem. You attach the hook clips once, to the adapter, and then it is much easier to swap transistors. Simple idea, don’t know why it didn’t cross my mind first 🙂

I used a piece of 6cm (length) times 4cm (wide) plated through hole proto-board, with a 14 pins ZIF socket and 3 pins for where the hooks should clip.

Proto-board assembly

I decided to use the same numbering scheme as a GM328a component tester which I also own and got used to:

3D Printed case

I wanted to protect the circuit board from accidental shorts, thus a small 3D printed case would not hurt. After a quick design in FreeCAD (and a lot of trial and errors for hole alignments) here is the result:

4 M2x5 self tapper screws were used to hold the case together while the board is sandwiched in-between.

I printed the labels with black background and glued them on the case using normal paper glue. The trouble is that the printed labels started to get some spots where the white paper can be seen, and I retouched them with black ink.

And here it is at work:

DCA75 Comparison with GM328a

The GM328a also works, but it has a quirky display of leakage values. The collector leakage current is shown as ICE0 (as in ICE Zero).

Testing a bad Germanium transistor (GM328a vs DCA75)

However, DCA75 comes with a software that plots transistor / diode charts – which is very nice when needed. GM328a is still more versatile since it also measures inductances, capacitors including ESR, etc. It also does not require 7 button clicks to get to scroll to the IcLeak line (like the DCA75 does, when used standalone and not attached to the PC).

At least I will use the DCA75 more, since I almost never use it due to the hook clips attachment method.