7 MHz SSB Transceiver
Carrier oscillator is a crystal controlled oscillator using two numbers of BC548. The circuit does not use any coils or turned circuits. First BC548 is used as oscillator second BC548 is used as buffer. The carrier oscillator frequency is offset by 1.5 KHz above ladder filter (IF) frequency. The carrier oscillator frequency can be varied slightly by adjusting the trimmer in series with the crystal. The metallic enclosure of the crystal should be grounded for increased frequency stability.