Hello Time-Nuts, Bob's comment, "Down in the typical DIY basement, doing all that “stuff” may not be very easy ….." struck a nerve. Two pictures are attached. I call it RUFUS - RUbidium Frequency Ultra Stable. Inside the vacuum chamber is an LPRO-101 mounted to that massive aluminum lid. The chamber is temperature controlled via the kapton heaters around the circumference and the power supply is a slightly modified Acopian Gold Box 'A' series unit. The rubidium EFC is brought out, but usually not driven. Most often it is run open loop with adjustments to the C-field (which has also been brought out of the chamber) every couple of months. It runs very well, and at the pressure I keep it has very little aging. RUFUS lives under the stairs in the basement. Regards, Skip Withrow