I spent most of the holidays visiting relatives. and had quite a bit of time to work on something I had been thinking about doing for a while. I have been following the development of the Simple-Ceiver that Pete N6QW has been posting on his blog. N6QW.blogspot.com .
Pete spends a lot of time going through the design of a DC receiver that is later converted to a single conversion heterodyne receiver for 40 meters. He goes through the design using LTSpice to simulate each stage before he builds them. This powerful tool allowed him to optimize the circuit design before melting any solder.
I have a bunch of 12 mHz. crystals left over from the IF amplifier for the Specan, so I could use the same frequency scheme that Pete used. I plan on using a version of the SI5351 VFO I had built for the "Canned Frog" transceiver. Different from Pete's circuit I will use another clock output from the SI5351 for the BFO.
Link to schematic at https://www.dropbox.com/s/dersy23jgj6h37c/Simple-ceiver-schematic.pdf?dl=0
After drawing the schematic and getting it checked by Pete, I did a single sided board layout using mostly surface mount components. I did not have surface mount versions of the ICs for the AF amplifier so I did the layout with extended solder pads for the leaded components. Although I plan on using the SI5351 for the BFO, I decided to add the BFO oscillator to the board.
Etched the board now to start building and testing the receiver, first the audio amplifier stages.