Does anyone know the aging and temperature specifications of a Motorola T5829A "Ultra High Stability Oscillator"? This is a 5 MHz standard containing an OCXO. After a day of operation, the next 24 hour drift was 2.5E-9 lower, but change due to temperature variations is unknown. A nearby HP-105B showed very little change. I need to determine a reasonable calibration interval. Hopefully aging will decrease with time. Thanks, Joe, W7LUX