ATU is based on a PI Network. This design uses two Miniature
Tuning Capacitor-AM from Rapid electronics . 1 pole 12 way rotary switch from
Rapid electronics. One T68-2 Toroid core from Sycom 20 swg
wire and two BNC sockets. The ATU work from 7mhz to 50 mhz. The Toroid coil is
made up of 33 turns of 20 swg wire. The coil is taped every 3 turns. This sits
on the back of the 12 way switch. The tuning capacitors have both oscillator and
antenna connected together to give about 0-200 pf
G8GRL's
QRP ATU
Parts
List
2 MINIATURE TUNING CAPACITOR-AM (RC) 12-0255
Rapidelectronics
1 1 POLE 12 WAY ROTARY SWITCH (RC) 79-0100
Rapidelectronics
1 T68-2 Toroid core Sycom
2 BNC Sockets
1 Box
1 20
swg wire