LO board provides all oscillator signals needed for signal conversion and mixing. The board consists of the following components: – LO first oscillator realized by U2 – SI570 (570CAC000141DG), 3 switchable low pass filters: 10.8-15MHz; 15-24MHz; 24-39MHz. Filter switching is
RX MIXER standard is ADE-1 diode ring mixer. Here described is optional high dynamic range H-mode mixer. The schematic and original H-mode mixer concept has been designed by Colin Horrabin G3SBI and further developed by Martein Bakker PA3AKE. PCB component
RF MIXER board does all RX/TX signals on IF and operation frequencies. On receive the signal comes on CX3 coaxial connector, then passes (or not) through input attenuator R10,R13,R14, then via switches come to BPF board. IF TRAP circuitry consists
Power amplifier building process: Power amplifier consist of two sandwich nested printed circuit boards – PA linear 55W board and low pass filter module.
Here is some pictures of LO board – ready and shielded Copper straps are added in order to improve ground on the board
By now all printed circuit boards are ready and populated. We have also some boards – completely tested and aligned: 1. IF/AF board 2. RF MIXER board 3. LO/tones board. 4. Front panel assembly – CPU, LCD/switches boards 5. Both