Home > Designs > G3ZVCmkII

This project is under Development
    
The architecture is very similar to the original G3ZVC board, however, it is now Arduino shield compatible,  has positions for two internal SI570 oscillators (VFO and BFO) and the demodulator has been upgraded to output IQ for SDR applications.
 
 There is no attempt to provide LNA/Buffer drive  IO at the mixer RF port. 
 A  2 layer PCB has been produced it has provisions for operation up to 23 cm.  
  There are interesting possibilities in building a four layer extension board for a relatively low cost extension to 10GHz and above using sliding IF techniques.
The board can be looked at as a partial transceiver minus LNA, PA , AF amp and controller (Arduino) or a set of transceiver building blocks:
•	Microphone Amp.
•	TX IF generator.
•	Up Down converter.
•	Direct conversion SDR receiver.
The  LO's (SI570) can be on or off board, the off board choice allowing the LO generation without programming issues. 
With the two SI570 on the board it could be used as Arduino controlled VFOs for such things as Collins TCS12 setups! By chance the microphone amp would also work to replace the carbon microphone of a TC12 transmitter.
The current board contains a set of all the IF components needed,  with possibly some questions as to SSB AGC performance (software).  The IF amplifier in this configuration is extremely small and could present some assembly problems if not done professionally. There are pins available to extract the IF circuits from the board to a sub board that could contain the old Plessey circuits or some other IF circuitry.