There are conflicting requirements regarding temperature in Rb's: - For best performance, the rubidium and quartz oscillators must be kept at a high and stable temperature. - For reliability, the supporting electronics must be kept at a lower temperature.
The heater takes care of the high temperature. The stability of the temperature can be improved by increasing the thermal mass, i.e. adding a block of aluminium or copper. The electronics can be kept cooler with a heatsink, and forced ventilation if needed. When you stick both the electronics and physics in a small package, this becomes more difficult. For the PRS-10 some form of heatsink is pretty much required to keep the electronics cool enough. Although I seem to remember reading somewhere that the "benchtop" heatsink they offer now is lighter than older units. If the room temperature is not stable enough, you might want to increase the size of the heatsink and add a fan. This reduces the temperature swing inside the unit, while still cooling the electronics, at the cost of increased power draw for the heater. On Wed, Oct 21, 2020 at 5:38 AM Hal Murray <[email protected]> wrote: > > > I spent a lot of years buying Rb’s and putting them on small heatsinks. > I > > always was disappointed in their reliability. That continued to be the > case > > up to the point that the baseplate temp’s got into the 40C region. In my > > case, that took a fan …. > > How well did it work if the heat sink wasn't small? What is your version > of > small? > > Do you have any data (or vague memories) of how much it helps to orient > the > heat sink so the fins are vertical so they encourage warm air to flow up > past > the fins? > > -- > These are my opinions. I hate spam. > > > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
