Six months into building a 7 MHz SSB transceiver from scratch using mostly through-hole components. Finally got the receiver section working reliably - using single conversion superhet design with 9 MHz IF and mechanical filter.

Transmitter uses balanced modulator approach with MC1496 generating DSB, followed by crystal filter for sideband selection. Getting about 25W output with IRF840 in the final stage, class AB configuration. ALC circuit keeps things clean and prevents overdrive.

Next challenge is integrating the synthesized VFO - building Si5351-based design that covers 7.000-7.300 with 1Hz resolution. Planning to use Arduino for band/mode switching and frequency display.

Construction is modular approach with separate boards for each function connected via short coax jumpers. Keeps RF stages isolated and makes troubleshooting much easier.

Nice project! For your power level, consider the MRF477 pair instead of single IRF840 - gives better linearity for SSB work though parts are getting hard to find. Make sure your ALC has fast attack, slow release characteristics.

Impressive build! I'm curious about your mechanical filter choice for 9 MHz IF. Are you using surplus Collins filters or something more modern? The selectivity characteristics make a huge difference in receiver performance, especially for contest work.

Watch your VFO harmonic suppression when you integrate the Si5351. Round frequency choices make calibration easier, and keep harmonics away from ham bands as much as possible. The synthesizer approach gives excellent stability compared to LC oscillators.