[time-nuts] Neat little cesium box

[Tom Van Baak]

Without spilling too many more details, can you say approximately what level of frequency accuracy or stability you need per year? Also, to the nearest decade, what is "relatively cost-conscious design"?

I ask because a CSAC costs on the order of 1500. Note it runs out of the box (you don't need to buy from a third party in a fancy enclosure). If you don't need that level of long-term performance consider a high-performance TCXO.

If power is a much greater limiting factor than budget use both; fire up the CSAC once a day (or week, etc.) for a few minutes to correct the VCTCXO. That way you get both low power and high accuracy.

/tvb

----- Original Message ----- 
From: "Gregory Muir" <engineering at mt.net>
To: <time-nuts at febo.com>
Sent: Thursday, June 13, 2013 5:15 PM
Subject: [time-nuts] Neat little cesium box


> Tom,
> 
> Thank you for your concern.  I unfortunately cannot disclose many details about the proposed project only to say that the application transcends much of the typical "Time-Nuts" areas of normality.  At present we are evaluating typical frequency references to see if they will fit into this project.
> 
> What I can say is that phase noise is of little interest but log-term frequency drift is.  The completed unit will unfortunately not see GPS signals during most of its lifetime, be constrained to a weight not exceeding 20 lbs, be considered non-recoverable (disposable) due to areas of deployment thereby require a relatively cost-conscious design, have no access to a source of power let alone any natural power-producing resources and have an expected lifetime of 10-12 years without maintenance access.
> 
> Most of the problems have been solved including the power source.  This is not your typical kitchen table project.  And, as new frequency references are developed and the design feasibility phase is still open, small and minimal power-consuming products such as the Novus unit will garner our attention.
> 
> Thanks for your offer,
> 
> Greg
> 
> On Thu, 13 Jun 2013 10:59:01 -0700, "Tom Van Baak" wrote:
> 
>>Greg,
>>
>>That URL confuses "atom" with performance. Calling something "cesium" in no way conveys the actual accuracy or stability of the device actually being offered for sale. A CSAC is not a 5071A is not a cesium fountain is not a >GPSDO. That's why we use statistics (ADEV) instead of the periodic table.
>>
>>In recent years small, compact, low-voltage, low-power TCXO, OCXO, rubidium, and cesium oscillators allow companies sell products called "quartz", "rubidium", and "cesium" with no regard to actual time or frequency or >noise specifications and performance plots. Even snake oil has an ADEV.
>>
>>Contact me *off-line* about your client and your actual requirements.
>>
>>/tvb
>