[time-nuts] Re: Sparkfun lists SA.35m

[Magnus Danielson]

Hi,

What you do is that you servo the semicondoctor laser to the transition,
as you do that with sufficiently narrow laser you can utilize the CBT
mode operation which has additional benefit rather than just replacing
the rubidium lamp with a semiconductor laser. Getting a laser in 780 nm
range isn't all that hard in itself, I have a bag of those lying around
for experimentation, not that they are good enough for this, but well,
it would be fun.

Cheers,
Magnus

On 2021-04-03 16:51, Dana Whitlow wrote:
> I knew about the use of the VCSEL, but I'd bet a good dinner that it's not a
> Rubidium laser!  Last I heard, none of the elements in that corner of the
> periodic table were semiconductors, and it's hard to imagine a vapor-based
> VCSEL.
>
> Dana
>
>
> On Sat, Apr 3, 2021 at 7:31 AM Lux, Jim <jim at luxfamily.com> wrote:
>
>> On 4/3/21 4:22 AM, Dana Whitlow wrote:
>>> "rubidium laser" ???
>>>
>>> Dana
>> I don't know about the MAC, but the CSAC uses a VCSEL to shine through
>> the gas cell.
>>
>> The MAC is a pretty big thing compared to the CSAC - it's in the usual
>> 2x2" package and draws 5-8W (after warmup)
>>
>>> On Sat, Apr 3, 2021 at 2:15 AM Poul-Henning Kamp <phk at phk.freebsd.dk>
>> wrote:
>>>> I know it's not a particular outstanding atomic clock, but I was still
>>>> surprised to see that Sparkfun lists the SA.35m for $1995...
>>>>
>>>>          https://www.sparkfun.com/products/14830
>>>>
>>>> Not in stock though...
>>>>
>>>> --
>>>> Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
>>>> phk at FreeBSD.ORG         | TCP/IP since RFC 956
>>>> FreeBSD committer       | BSD since 4.3-tahoe
>>>> Never attribute to malice what can adequately be explained by
>> incompetence.
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