For my QRP transceivers I prefer to use a resonant antenna. However, sometimes you can’t deploy the antenna exactly how you want, and then an antenna tuner can be very handy. On the internet I found two antenna tuners that I liked to buy, however, they were from companies outside Europe and they were not subscribed to the IOSS system. Having to add VAT and handling fees on top of the already high kit price was a no-go for me. Therefor I studied the schematics and the manuals of both antenna tuners and figured out I could easily buy the components on AliExpress and build the Z Match antenna tuner myself for a fraction of the cost. Well, actually, the costs remained the same, but I could make more ATU’s (or kits), so the members of my radio club could have a go on one of them themselves. 😉

Manual and instructions

The ATU I’m going to clone is the Emtech ZM-2. If you google for “ZM-2 manual pdf” you’ll get some hits with the orignal detailed instructions and parts list. It will be this manual that I’ll follow to build this ATU. For some parts there are no specifications given. For those I’ll take an educated guess on what the part should be.

Parts List for one antenna tuner

Story time!

Step 1: Preparing The Poly Capacitor
Step 2: Preparing The Enclosure
Step 3: Winding Toroid T1
Step 4: Winding Toroid T2