PDF DOWNLOAD: Chapter 10
VARIABLE FREQUENCY OSCILLATORS
- Drift is a big deal today
- Low frequency VFOs drift less than high frequency VFOs
- JFET transistors
- The oscillator circuit
- The buffer, final amplifier, and output filter
- The 50 secrets of avoiding drift
JFETs, single-side PC boards, cast metal box, multiple NPO caps, small variable caps,
precision voltage regulation, and more
- Vernier tuning
- Varactor tuning elements – advantages and disadvantages
- A precision power supply
- A voltage doubler power supply for battery use
Square wave generator with a multivibrator
Squaring up the square wave
Charge pump, diode/ capacitor voltage doubler
Schottky diodes for efficiency
- Temperature compensation methods
Positive coefficient capacitive trimmer compensation
How to adjust the compensator
Thermistor/ varactor temperature compensation