This workshop reviews progress on a compensation subsystem for proven XO-based oscillators using a temperature sensor and microcontroller. The design approach is the microprocessor-controlled crystal oscillator, or MCXO, which is designed to assure a high degree of frequency control in a wide temperature range. The following topics are considered important with regard to MCXO design:

• Fundamental temperature characteristics of the crystal
• Hysteresis of the crystal
• Activity dips
• Perturbations of the temperature characteristics of the crystal
• Short term repeatability of the crystal frequency
• Long term repeatability of the crystal frequency (aging)