Picardy 2020

A reinterpretation of the Picardy 2m SSB transceiver by F6FEO combined with the Anglian 3L transverter.

• Designed in KiCad
• Meant to be used with a microwave transverter
• But also stand-alone 28MHz and 144MHz (The IF bands)
• Using a STM32F103C8T6 controller
• Si5351 clock source (generates 3 clocks)
• An LCD display
• Discarded ideas
• Include a Lars Widenius GPSDO originally published on eevblog
• Offer a 10MHz output refclk for a transverter
• Instead, have a 25MHz ref input, and use a LeoBodnar reference

TODO before ordering the PCB

• Microphone input

• Verify microphone pinout for MH-42

• CW

• Does the trick with the DC bias to leak the LO work ?
  • Not tested, but plan B done (J306)
  • Use an additional PWM output for plan B?

• Put sidetone volume setting before RV303?

  • Hook up to LM375 BYPASS?

• Si5153

• Check desired frequencies can be achieved:
  • LO1 = 28 - 4.9152 + VFO
  • BFO = 4.91521
  • VHF-LO = 144 + 28 and 144 - 28

PCB Assembly Plan

1. DCDC converter for 8V and LDOs * Check output voltages * Check drop under load

2. STM32F103C8T6 * Programming * Sidetone low-pass * Probably need to do a UI proto already

3. Si5153 * Check I2C works

4. 8V and 5V relay * Check switching with microcontroller and validate resistors

5. Baseband

6. Crystal filter shape
7. RX and TX filter shape
8. Receive path: IF mixer, crystal filter relay, IF AGC, BFO mixer, AGC measure, AF amp, SPKR
   • Verify LO levels into SA602A: at least 200mVpp

9. Transmit path: Mic amp

10. Anglian

11. LO filter shape
12. LO amp. Mixer needs +7dBm
13. All passives
    • Verify correct voltages for amplifiers
    • Verify PIN currents (Between 20mA and 60mA, below 0.8V)
    • Verify filter shapes
14. IF amplifiers, both RX and TX
15. VHF amplifiers
16. VHF bandpass filter

17. Mixer

18. External switching relay