Re: [time-nuts] Re. DIY atomic "resonator"

Hi, On that note we have Rick Karlquists article showing how he replaced the traditional syntheis chain with an oscillator at the target frequency, locked to the lower frequency. Benefit is in the phase-noise. This was from the fine work on the 5071A. This approach can be used for rubidiums

Re: [time-nuts] Re. DIY atomic "resonator"

Typically External Cavity diode lasers use either the Littrow or the Littman-Metcalf configurations. A typical Littrow configuration is: http://www.moglabs.com/uploads/2/4/2/1/24212474/manual_ecd_rev4.20.pdf Alternatively a cat eye external cavity can be used:

Re: [time-nuts] Re. DIY atomic "resonator"

discharge tubes > On Apr 12, 2017, at 2:18 PM, jimlux <jim...@earthlink.net> wrote: > >> On 4/12/17 10:28 AM, Dave B via time-nuts wrote: >>> On 12/04/17 17:00, jimlux wrote: >>> >>> Subject: Re: [time-nuts] Re. DIY atomic "resonator&q

Re: [time-nuts] Re. DIY atomic "resonator"

Hi There are papers from the mid 90’s talking about improving the GPS Rb’s. Those parts are as far as I know the best “production” Rb’s out there. The main comment seems to be that phase noise (in it’s various forms) is a major contributor to the stability of the Rb’s…. Bob > On Apr 12,

Re: [time-nuts] Re. DIY atomic "resonator"

Many decades ago, QST had an article about the "Monode" RF noise generator. No it wasn't an April Fools joke; the Monode is simply a light bulb. You can probably download the article from the arrl.org web site. HP used to sell a fluorescent tube embedded in a waveguide as a noise source.

Re: [time-nuts] Re. DIY atomic "resonator"

Hi *All* incandescent lamps emit RF ….. They are a resistive device that is heated to well above room temperature. People do use them in simple noise figure meters. The inductance of the filament in a typical bulb restricts the bandwidth a bit. The are designs from at least the 1960’s

Re: [time-nuts] Re. DIY atomic "resonator"

Looking back at the dialog I started on Rb’s and the repeated returns to that subject allow me to make some comments, observations and recommendations.. I stayed on purpose away from participating but learned a lot. It also resulted in some off list dialogs with members working on the

Re: [time-nuts] Re. DIY atomic "resonator"

On Wed, Apr 12, 2017 at 11:18:00AM -0700, jimlux wrote: > Yep. There's been a fair amount of work over the past decades on using > modulated reflectors for measuring antenna patterns (e.g. on phased > arrays). You can have a diode/dipole suspended by resistive leads (with > an impedance of

Re: [time-nuts] Re. DIY atomic "resonator"

Some incandescent lamps can emit RF. http://www.rexophone.com/?p=1081 http://www.radiomuseum.org/forum/rustika_lightbulb_fm_measurements.html On Tue, 11 Apr 2017 18:09:52 +, you wrote: >Apparently fluorescent tubes continuously emit a lot of other microwave >signals. I once built a

Re: [time-nuts] Re. DIY atomic "resonator"

On 4/12/17 10:28 AM, Dave B via time-nuts wrote: On 12/04/17 17:00, jimlux wrote: Subject: Re: [time-nuts] Re. DIY atomic "resonator" Message-ID: <b3926cda-b4ff-2508-1be6-57c2fecf0...@earthlink.net> Content-Type: text/plain; charset=utf-8; format=flowed On 4/11/17 11:09 AM,

Re: [time-nuts] Re. DIY atomic "resonator"

On 12/04/17 17:00, "Tom Van Baak" wrote: > It turns out that OP (Andre) would like the readings of his vintage Black > Star (UK) Nova 2400[X] 8-digit 2.4 GHz bench frequency counter to be accurate > and stable to the 8th digit. That's all. The internal XO or TCXO is not good > enough for that

Re: [time-nuts] Re. DIY atomic "resonator"

On 12/04/17 17:00, jimlux wrote: > Subject: Re: [time-nuts] Re. DIY atomic "resonator" > Message-ID: <b3926cda-b4ff-2508-1be6-57c2fecf0...@earthlink.net> > Content-Type: text/plain; charset=utf-8; format=flowed > > On 4/11/17 11:09 AM, Mark Sims wrote: >> Appa

Re: [time-nuts] Re. DIY atomic "resonator"

or to build his own > atomic clock from scratch. It's just an 8 digit counter. > > /tvb > > - Original Message - > From: "Andre" <an...@lanoe.net> > To: <time-nuts@febo.com> > Sent: Tuesday, April 11, 2017 12:31 AM > Subject: [time-nuts] Re. DIY

Re: [time-nuts] Re. DIY atomic "resonator"

I investigated police radar stuff a long time ago, and for a while had an old X band unit shaped just like a searchlight, with analog meter. What I learned then was that even on the newer units, the tuning fork was specified to provide an independent means to verify the accuracy of the unit in

Re: [time-nuts] Re. DIY atomic "resonator" 6GHz synthesizer from ADI

But it is as Richard said and after he sent it I remembered reading about it in the "Quantum beat". The trick is to get that accurate frequencies sideband to land on the RB or CS frequency. Just 1 sideband. So using a large step synthesizer and then another to get the finer detail is a reasonable

Re: [time-nuts] Re. DIY atomic "resonator"

On 4/11/17 11:09 AM, Mark Sims wrote: Apparently fluorescent tubes continuously emit a lot of other microwave signals. I once built a homodyne doppler "speed" radar kit (used a coffee can for the antenna). The way you calibrated it was to point it at a florescent tube and and adjust the

Re: [time-nuts] Re. DIY atomic "resonator"

clock from scratch. It's just an 8 digit counter. /tvb - Original Message - From: "Andre" <an...@lanoe.net> To: <time-nuts@febo.com> Sent: Tuesday, April 11, 2017 12:31 AM Subject: [time-nuts] Re. DIY atomic "resonator" > Hi all. > > As a first st

[time-nuts] Re. DIY atomic "resonator"

Apparently fluorescent tubes continuously emit a lot of other microwave signals. I once built a homodyne doppler "speed" radar kit (used a coffee can for the antenna). The way you calibrated it was to point it at a florescent tube and and adjust the reading to a specific value.

Re: [time-nuts] Re. DIY atomic "resonator" 6GHz synthesizer from ADI

Hi If you make the cells in the basement (or even in most factories) the ability to have a wide range synthesizer will come in handy. The whole “6.834xxx GHz” thing is dependent on a number of variables. It is not at all uncommon to produce cells that come out 10’s or 100’s of KHz off of the

Re: [time-nuts] Re. DIY atomic "resonator" 6GHz synthesizer from ADI

You always want two frequency sources. One generates a carrier frequency offset many MHz from 6.834 GHz and the other frequency source modulates the carrier with a sideband that is at the exact ~6.834 GHz frequency that finds the atomic line. The sideband is in turn modulated with audio to find

Re: [time-nuts] Re. DIY atomic "resonator" 6GHz synthesizer from ADI

When I read about the frequency generation in the Rb or CS there are normally many numbers associated with the actual frequency. Down to at least the 1 Hz level. Many of these PLLs are intended for multi-KHz steps. I speculate you might need 2 PLLs one thats very fine in I hz increments that gets

Re: [time-nuts] Re. DIY atomic "resonator"

On 4/11/17 9:22 AM, Magnus Danielson and Rick Karlquist wrote: This is in the category of projects where if you were qualified to do it, your time is far too valuable to do it for the amount of money you would save. This is the type of project you do not to save any money, but to spend and

Re: [time-nuts] Re. DIY atomic "resonator" 6GHz synthesizer from ADI

the are 6GHc synthesizer chips from ADI available see here http://www.analog.com/en/analog-dialogue/articles/design-a-direct-6-ghz-local-oscillator.html 73 KJ6UHN Alex On 4/11/2017 8:29 AM, Attila Kinali wrote: On Tue, 11 Apr 2017 07:31:01 + Andre wrote: Has anyone

Re: [time-nuts] Re. DIY atomic "resonator"-- replacing SDRs

YES SDRs [step Recovery Diodes] is hard to find today, but there many-- PIN -- diodes, which exhibits that effect, even some standard rectifier diodes could be used for, despite of that Magnus is right, today are better solutions available e.g. PLLs with 10GHz prescalers 73 KJ6UHN Alex On

Re: [time-nuts] Re. DIY atomic "resonator"

To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Re. DIY atomic "resonator" Hi If you are going to do a Rb, probably the best place to start is with a salvaged physics package out of one of the telecom Rb’s. That would let you get the “easy bits” worked out on

Re: [time-nuts] Re. DIY atomic "resonator"

Hi If you are going to do a Rb, probably the best place to start is with a salvaged physics package out of one of the telecom Rb’s. That would let you get the “easy bits” worked out on your side of the design. It would also let you lear how to address a few of the more complex items sorted

Re: [time-nuts] Re. DIY atomic "resonator"

On 04/11/2017 05:54 PM, Richard (Rick) Karlquist wrote: On 4/11/2017 12:31 AM, Andre wrote: Has anyone else either built an atomic clock around a bare Rb lamp module "core" or attempted Not a DIY project, but I was the RF designer on the HP 10816 rubidium standard, which never made it

Re: [time-nuts] Re. DIY atomic "resonator"

On Tue, 11 Apr 2017 07:31:01 + Andre wrote: > Has anyone else either built an atomic clock around a bare Rb lamp module > "core" or attempted > > to make a hydrogen maser? Building my own Rb vapor cell standard or H-maser is on my list of Things-I-have-to-do-before-I-die

Re: [time-nuts] Re. DIY atomic "resonator"

On 4/11/2017 12:31 AM, Andre wrote: Has anyone else either built an atomic clock around a bare Rb lamp module "core" or attempted Not a DIY project, but I was the RF designer on the HP 10816 rubidium standard, which never made it to product introduction (a half dozen working pilot run

Re: [time-nuts] Re. DIY atomic "resonator"

Andre Now I know your location. So your questions make more sense to me. With respect to home brewing atomic standards. There have been numerous threads on time-nuts around this. The fact is technology has obsoleted so many technologies that things like Rb references can be had far cheaper used

[time-nuts] Re. DIY atomic "resonator"

Hi all. As a first step, I wanted to build a specific hydrogen line (1.420 GHz) preamp. Seems that some fluorescent tube starters do emit a very brief burst at around 1.4 GHz during a specific portion of the initial switch-on surge when cold and actually observed this here. Also relevant,