Homebrew Portable T-Match ATU

VK1AD Portable T-Match Antenna Tuner (ATU) mounted in a plastic case

T-Match ATU Schematic – 3.5 to 52 MHz power rating 80 watts

L1 is tapped at turns: 1, 2, 3, 4, 6, 8, 10, 13, 16, 20, 26 and 37.

Front panel – Vernier dials and a 12 position rotary switch knob, top cover is on.

The vernier dials enable logging of each capacitor setting, which can be repeated at the next activation. This has so far proven sucesful for the 27.2 metre End Fed.

Rear panel – 2 x SO239 sockets, Spring Loaded Long Wire Antenna Terminal and Ground Screw

Each double-gang variable capacitor is isolated from the vernier dial by a plastic insulated 6 mm coupler. Rear gangs are in use.

Internal wiring is PTFE insulated.

FT-857D T-Match ATU and a 27m long wire antenna on 3.620 MHz

Homebrew T-Match ATU

Icom IC-703 and T-Match ATU in action at Mt Donna Buang Yarra Ranges National Park

20 Dec 18 – T-Match ATU combined with a 27m End Fed Antenna at Mt Donna Buang VK3/VC-002

27 metre End Fed Long Wire Antenna

Icom IC-703 combined with the T-Match ATU and a 27m End Fed antenna at Mt Big Ben VK3/VE-105

17 Dec 18 – SOTA gear

17 Dec 18 – Mt Big Ben VK3/VE-105

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