[time-nuts] Re: MHM-A1 maser temperature stabilization

[Bob Camp]

Hi

Ok, but do I need  > 800 L of the stuff ? 

I assume it’s called Autoclaved Aerated Concrete over here. If so, it has about half the thermal 
capacity per L of “normal” concrete. That puts it in the range of 700 to 800L being the same as 
my 250L water guess. 

Yes, having something that is self supporting and not going to leak is a plus. I’m not debating
that point in any way. I’m still trying to scope the project. 

So what would 800L look like? 

Because I’m still lazy, say this is a 3/4 cubic meter right now without any added mass.. I could 
go measure it all, but that’s pretty close. Roughly speaking 700 to 800L of added “stuff” doubles 
the volume of the enclosure. That would take some fairly detailed planning. Thus the need for a 
bit of checking on the order of magnitude ……

Also, just for the record, 250L of water isn’t a very attractive answer either. Oopss … crash ….
splash … sparks … sparks … smoke ….

Bob

> On Jan 17, 2023, at 3:36 PM, Poul-Henning Kamp <phk at phk.freebsd.dk> wrote:
> 
> --------
> Bob Camp writes:
> 
>> Coming back to the basic question:
>> 
>> 	Concrete *or* water, how much do I need?
> 
> As I said: Forget the water and look into 2" aerated concrete:  It's
> cheap, they probably have it at the local home depot, and it won't
> throw your back out or leak.
> 
> -- 
> Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
> phk at FreeBSD.ORG         | TCP/IP since RFC 956
> FreeBSD committer       | BSD since 4.3-tahoe    
> Never attribute to malice what can adequately be explained by incompetence.