[time-nuts] Making a HP 10811 better

[WarrenS]

Bert wrote: >"would not feel comfortable tearing into the unit."

I tend to agree, First rule is "do no harm",
which is why I start with reversible things that can be done using just 
external stuff.
The second rule does NOT apply though, "Don't fix it, if it aint broken"
Of course if it is already broken, or you have lots of them, or they are not 
yours, or you're getting paid for it, then go for it.

BUT
I find it amazing that you are more concerned about opening the unit than
you are about sticking it down a deep hole from which it may never return if 
something goes wrong.
I think I'd rather have mine on the bench even if it was in parts, than to 
lose it to the center of the earth.
BUT I must Add, good idea if you want a nice constant passive "green" 
environment with a very long time constants (maybe 1/2 year TC?)

ws

**********************
From: <EWKehren at aol.com>

>I would not feel comfortable tearing into the unit.
> Controlling its environment and power to it yes.
> I did that with a 10811 and a 10544 years ago by drilling a 20 foot  hole
> in my Dallas backyard lowering the units in it with support electronics in
> place and sealing the shaft with individual sand bags each with a numbered
> string, so I could pull them out one at time when I had to get to them. 
> Did
> not  have the equipment I have today but I did manage to borrow a 5061A 
> for
> set up.  Here in Miami being right on the water it is not an option. When 
> I
> relocate  from Miami to dryer grounds I may repeat it with a Rubidium.
> Bert
>
****************************
> In a message dated 3/28/2010 11:52:14 A.M. Eastern Daylight Time,
> warrensjmail-one at yahoo.com writes:
>
> Bert  asked
>
>> "why would  I  want to mess with them at all if  they are already under
>> 1E-12?"
>
> Don't know about  you, The reason I'd mess with them is cause I'm nuts
> and can make them  even better.
> And Allan variance is not everything.
> Have you plotted  their Freq change over time with better than 1E-12
> resolution?
> If you  are a True NUT, I'm betting you would see things that would make
> you  sick.
> Things such as line freq spurs, Freq jumps, the effects of:  changing
> temperature, changing PS, changing time, changing Load, partial  injection
> locking to other osc friends around them, and maybe even to the  changing
> moon.
>
> Don't forget the Basic Nut Cake pledge.
> If it can  be made better then it is not good enough
>
> Or for the more practical  answer;
> Cause I can make mine good enough with some help from two of its  friends,
> named GPS and Rb, that I do not need a Cs primary  standard.
>
> ws
>
> *********************
>
>> Good  morning
>> I have a more fundamental question. Having three 10811-5071  all with 
>> Allan
>> Variance from 1 to 100 Hz well below 1 E-12 one as low  as 6 E-13 why 
>> would
>> I  want to mess with them at all?
>>  Bert Kehren
>>