[NLRS] Dewer

[Dr.Gerald Johnson]

Maybe Toronto surplus. 10 litre is a bit big for a Thermos bottle, but they 
used to be made like a dewar, aluminized and double glass walls 
evacuated.

I've had a dewar made by a glass blower, but we didn't talk price or 
budget. That one had a couple spiggets out the bottom which made it 
a lot harder to make.

I suspect some of the modern foam insulations are as good as the 
dewar and much lighter as the containers for liquid nitrogen 35 years 
ago already around LN vacuum pumps were made of foam.

Schools like Iowa State University have surplus stores also, a good place 
to look. I've not been the ISU surplus sale for a couple years. Its just one 
afternoon a week and there is a crowd at the door waiting for its 
opening.

73, Jerry, K0CQ

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