Hang in there as we soon will complete the PNP journey to develop a rig that employs PNP transistors throughout the topology. So far, we have presented simulations of the circuit modules which can be duplicated by blog readers using LT Spice.
Essentially, the 2N2907 and 2N2905 are doing the heavy lifting and we have identified a P Type MOSFET to replace the IRF510.
Today's post adds the 2N2907 Microphone Amplifier stage. This stage cranked wide open can deliver about 29 dB of gain over the speech range 300 to 3000 Hertz. You will not get glowing reports about speech at 100 Hz, but your signal will have a lot of punch for breaking pileups running QRP power levels.
By way of recap, we have:
1) A 2N2907 Microphone Amp
2) A 2N2907 and 2N2905 Audio Amp
3) Two 2N2907's in the IF Module
4) A 2N2907 RF Amp/Tx Pre-Driver
5) A 2N2905 Driver Stage
6) P Type MOSFET for the Final Amp
7) Two ADE-1's for the PD/BM and Rx/Tx Mixer
8) Si5351 + Arduino for the LO and BFO
Yes, you guessed it still to come a block diagram and a recap posting of all of the circuit simulations.
See that was not too bad so now back to all of those mysterious menus hidden behind the ICOM IC7300 buttons.
TYGNYBNT
73's
Pete N6QW