Anyone using the ZM4 tuner ?

[DL6GCA]

I had bought the ZM4 tuner as a kit and built it up as lockdown project. It works really well.

Lockdown Projects

My latest lockdown project was adding a fan to the linear power supply in my shack. When I did a long run of CW QSO’s at 100W, a strange smell started coming from under my desk … in case you readers have any doubt, the smell came from the PS ! I found a very simple circuit here I took a 10k NTC resistor (there is one in every laptop battery pack, they look like two thin wires with a “drop” of plastic at the end), and a 10k multiturn trimmer (not 50k). The FET used was an IRF830, but…

Since I have tuned antennas for the QCX and otherwise the tuner is installed in the KX2, I sold it.

In the QRPshop you don’t get him to my knowledge any more… The store ends soon.

It is in any case a good working tuner.

73 Armin