[time-nuts] OT: Basics of voltage calibration?

Brian Kirby kilodelta4foxmike at gmail.com
Wed Mar 18 20:55:06 EDT 2009


There are two types of standard cells, saturated and unsaturated.  The 
saturated cells cannot take any physical abuse.  The unsaturated cells 
can be put in any position and can usually recover.  It may take six 
months....

Sometimes they get a bubble in the unit.  You can tap it out and allow 
it to stand and it may recover.

You can also remove a defective cell from the case and replace it...

Brian Kirby KD4FM

Max Robinson wrote:
> I have heard of standard cells being sent in for restandardization.  Is 
> there a type that can stand being shaken but not stirred?
>
> Regards.
>
> Max.  K 4 O D S.
>
> Email: max at maxsmusicplace.com
>
> Transistor site http://www.funwithtransistors.net
> Vacuum tube site: http://www.funwithtubes.net
> Music site: http://www.maxsmusicplace.com
>
> To subscribe to the fun with tubes group send an email to,
> funwithtubes-subscribe at yahoogroups.com
>
> ----- Original Message ----- 
> From: "Jean-Louis Oneto" <Jean-Louis.Oneto at obs-azur.fr>
> To: "Discussion of precise time and frequency measurement" 
> <time-nuts at febo.com>
> Sent: Tuesday, March 17, 2009 10:48 PM
> Subject: Re: [time-nuts] OT: Basics of voltage calibration?
>
>
> I suppose it was to to keep the electrolyt to slam around ;-}
> ???
> Jean-Louis Oneto
> ----- Original Message ----- 
> From: "Bill Hawkins" <bill at iaxs.net>
> To: "'Discussion of precise time and frequency measurement'"
> <time-nuts at febo.com>
> Sent: Sunday, March 15, 2009 4:24 PM
> Subject: Re: [time-nuts] OT: Basics of voltage calibration?
>
>
>   
>> Yes, never load a standard cell.
>>
>> It's standard practice to put a jumper across the terminals of a
>> galvanometer for shipping, so the needle (or mirror) doesn't slam
>> around.
>>
>> Some years ago, I got a standard cell from eBay. The terminals had been
>> shorted for shipping.
>>
>> Bill Hawkins
>>
>>
>> -----Original Message-----
>> From: Jürg Kögel
>> Sent: Sunday, March 15, 2009 7:36 AM
>>
>> A good reference is the old Fluke publication "Calibration - Philosophy
>> in Practice"
>> by Steve Spang. (1975)
>>
>> Be very carefull with standard cells! Never load a cell. Use the cells
>> only with high ohm null detectors.
>> A loaded cell need a long time for regeneration (or come back never to
>> the old value!)
>>
>> I think a good zener reference is a better practical solution for today.
>>
>> Juerg
>>
>>
>>
>> _______________________________________________
>> time-nuts mailing list -- time-nuts at febo.com
>> To unsubscribe, go to
>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>> and follow the instructions there.
>>     
>
>
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to 
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>
>
>
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>
>   




More information about the time-nuts mailing list