There are many people who want to listen whats going on in VHF 108 – 132 MHz. This vhf am converter converts a band between 106 and 150 MHz, so you can listen even 2m radio amateurs (144Mhz).
This vhf am converter is build with an vhf amplifier, one mixer and oscillator. After the input signal is amplified with T1 it is applied to a mosfet mixer and combined with the quartz oscillator output.
The tuning is between 6 and 30 MHz. The quartz frequency is fx = fi-fo where fo is output frequency and fi is input frequency.
L1 = 7 turns / 3 turn from ground
L2 = L3 = 3 turns
L4 = 4 turns / 1 turn from ground
L1 … L4 = CuEm SWG 20
L6a = 4 tunrs / SVG 36
L6b = 4 turns / SWG 24
L6a and L6b are build togheter on ferrite 3 x 6 mm
L5 = L7 = 0.82 uH
L8 = 1 uH
Quartz crystal = 100 …. 120 MHz overtone armonic 5