Superhet Receiver Design

Block Diagram

Pre-selector / Bandpass Filter

• Not shown
• Couples antenna to RF Amp and suppresses out of band signals
• RF Band Pass Filters

RF Amp

• Kits and Parts Universal Wideband Small Signal RF Amplifier

Mixer

• Kits and Parts Mixers
  • 9 MHz Diplexer for IF

Crystal Filters

• Located between First mixer and IF Amplifier
• SSB or CW filter
  • SSB4
• CW5

VFO/Local and BFO Oscillators

• VFO-003
  • Si5351A based
  • Arduino Pro Mini
  • OLED Display
    • Detachable for remote mounting
  • Controlled by Rotary Encoder
  • Temperature Controlled Crystal Oscillator
  • Triple output (uses 2 of the 3 outputs)
    • VFO for received frequency plus 9 MHZ

IF Amplifier

• Kits and Parts Hybrid Cascode IF Amp Module with AGC

Demodulator

• Kits and Parts Mixers
  • Replace Diplexer with Low Pass Filter for audio range