[time-nuts] Restoring GR 1120-AB Frequency Standard
fortime at bellsouth.net
Wed Aug 20 06:49:51 EDT 2008
Bruce, what was the diameter or how was the column situated to give those
----- Original Message -----
From: "Bruce Griffiths" <bruce.griffiths at xtra.co.nz>
To: "Discussion of precise time and frequency measurement"
<time-nuts at febo.com>
Sent: Wednesday, August 20, 2008 6:19 AM
Subject: Re: [time-nuts] Restoring GR 1120-AB Frequency Standard
> phil wrote:
>> Do you have a photo, would it be possible to build? I have a few flasks
>> mercury and a few 10's of thousands of mercury wetted relays that some
>> be cannibalized for electrodes. The trick here is how thin is that column
>> mercury. My guess the thinner the column, the finer the resolution or the
>> more it will travel with a small temp swing. Better yet, possible to cut
>> that thing open and fix it.
>> I know that's more time than it's worth.
>> Another thought, if the contacts have corroded in the mercury, perhaps
>> contamination, would it be possible to "burn" the contamination off.
>> Thinking of excessive voltage/current. Perhaps making it arc internally.
>> Trick would be to limit current not to explode the thing, perhaps using a
>> charged capacitor. Just a thought.
>> Oh, do you have the whole rack, all dividers and the clock? I bet the old
>> clock alone is worth a thousand bucks today. Seems like it was driven by
>> KC. My old standard was complete, a 5 or 6 foot rack and came out of an
>> Hamerland Radio plant.
> NBS used platinum wires in their mercury toluene thermoregulators.
> These were constructed from pyrex as it proved more stable than
> stainless steel.
> These themoregulators had a sensitivity of about 0.001C and were used to
> regulate the temperature of oil baths,
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