[time-nuts] SMPS or conventional?

[Luiz Alberto Saba]

I am thinking in an black aluminium finned heatsink, the size of the 
base plate, and a fan, controlled by an electronic thermostat (sensor 
direct coupled to the heatsink). Is that ok?

Em 21/10/2020 09:40, Wannes Sels escreveu:
> 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 <hmurray at megapathdsl.net> 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 -- time-nuts at lists.febo.com
>> To unsubscribe, go to
>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
>> and follow the instructions there.
>>
> _______________________________________________
> time-nuts mailing list -- time-nuts at lists.febo.com
> To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.