Posts tagged ‘LM258’

Wavetek 907 Repair, YIG Oscillator Teardown

As I mentioned in my previous posting, there was an issue with my Wavetek 907 microwave frequency generator. While everything was fine during my initial testing, the frequency display is now stuck with an out-of-range display and the adjustable frequency range is limited to between around 6.9 Ghz to 7.9 Ghz (instead of all the way up to 11 Ghz). My initial suspicion was that the PTC heater inside the YIGGunn oscillator was malfunctioning. But as it turned out, it was something else. Continue reading ‘Wavetek 907 Repair, YIG Oscillator Teardown’ »

Yet Another Semiconductor V/I Curve Tracer – I

Semiconductor curve tracers were frequently used in analog circuit designs many decades ago, at a time when discrete semiconductor devices were in dominance and ICs were scarce. While curve tracers are no longer widely used nowadays due to the ubiquity of digital circuitry and computer aided designs, they are still quite popular in the educational world and among hobbyists. In this and the next post, I will discuss some of the design considerations of a curve tracer that I built and show some real-world measurement results. Continue reading ‘Yet Another Semiconductor V/I Curve Tracer – I’ »