A lot of projects are in progress at the same time. One of the projects is a 70 MHz transverter with 27 MHz IF. It uses the same concept as the cb to 40 meter transverter described in one of my blogs.
I made a 43 MHz signal by mixing signals from a 18 MHz Xtal oscillator and a 25 MHz Xtal oscillator. The 18 MHz oscillator is a VXO.
The 43 Mhz signal is amplified by a amplifier using a bfy-90. This signal drives a SBL-1 alike mixer. Signal out of the mixer is filtered by 3 tuned circuits.
TX signal is boosted by a 4 stage amplifier to 1 Watt. It works but I am a bit worried about the stability.
The transverter was pretty deaf so I added a preamplifier using a bfy-90 and 2 tuned circuits in the input. It seems to work. I can hear a 0.1uV signal.
A 0.5 uV signal has a acceptable signal to noise ration.
Pictures and schematics will will be added soon
