My QRP Z-Match
Being very satisfied by the use of my first Z-match antenna tuner described above, I wanted a more compact one to use with my 5 watts FT-817 transceiver. Looking again on the web gave me useful information about such design, the solution being to use small variable capacitors that can be easily found in old portable AM broadcast receivers and a smaller toroid core.
Here is below the one I have constructed in a commercial Toko aluminium box. The size is 100 mm x 70 mm x 25 mm.
As it can be see on the pictures of the opened box, the two variable capacitors are very compact. A simple SRW bridge allows to indicate the best tuning positions and an additional 150 pF capacity can be switched on, to help tuning shorter wires if necessary. On the back, a switch allows to select for a balanced feedline or an asymetric feedline.
