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HF/VHF
Portable Mini Tuner

By Guy, de ON6MU
Schematic fig1

Parts list
alu box of 70mm X 40mm X 33mm
2 female PL 259 chassis
C1 = variable capacitor of 300 or better 500 pF
S1 = 10 or more posistion rotary switch
L1 = 0,7mm insulated
copper wire, 6 turns par connection closely together, 9mm
outside diameter (8mm inside)
taps every 6 turns and the last two sections (L1' and L1'')
4 turns spaced at 1mm and 3turns spaced by 2 mm
The coil
Wind
6 turns x - 2 connections on your switch (in this project
a 10-posistion rotary switch is used, being 8 times 6 =
48 + 4 + 3 = 55 turns) over a 7mm screwdriver (or simular
obkject hi) and make a tap every connection. Solder each
tap.
Solder
each tap to each connection of your switch and stretch L1'
(being 4 turns) at 1mm spacing and L1''(being only 3
turns) at 2 mm spacing. You can replace L1'' by 3 turns
of silver wire to allow better Q on higher frequencies (VHF).
Minituner insides...
Specifications
2 set manual operation
frequency range: 160m...6m (2m band if L1'' is silver, High Q switch, coil and close connections are used)
10 Watt +-
direct feed
compact design ideal for low power transceivers, like the Yaesu FT-817...
Homemade aluminum box


Don't forget to
check these out:
.ON6MU
Homebrew projects
.Radioamateur related projects
.ON6MU
Ham mods
.Modifications of transceivers
73"