Re: [time-nuts] H-maser drift

Thanks for that input John. > Le 21 nov. 2017 à 21:26, John Ponsonby a écrit : > . > 7. The RF discharge generates UV. This shines up the beam path and > illuminates the bulb coating in the region where the incoming atoms first > make contact with the bulb coating. This

Re: [time-nuts] ***SPAM*** Re: Why discipline Rubidium oscillator?

Oops, I should have mentioned: The unit was a Symmetricom MHM-2010 (I hope I got that right), except that it was built before the company was bought by Symmetricom (which was later bought by Micro-Semi in turn). This is an active maser, meaning a self-sustaining oscillator whose gain medium was

Re: [time-nuts] HP5065A C-field mods and optical unit mods

Luciano wrote: about the C field ten turn pot you write is a low TC pot. Normally a good Vishay pot is 20 PPM/C, This is in conflict with the 1PPM resistors ad voltage reference. In the schematic Corby posted, the potentiometer (used as a variable resistor) makes up a very small part of

Re: [time-nuts] HP5065A C-field mods and optical unit mods

Hi Corby, about the C field ten turn pot you write is a low TC pot. Normally a good Vishay pot is 20 PPM/C, This is in conflict with the 1PPM resistors ad voltage reference. What kind of pot do you have used? http://www.mouser.com/ds/2/427/533534-768216.pdf Luciano timeok

[time-nuts] GNSS signals (was: Why discipline Rubidium oscillator?)

On Mon, 20 Nov 2017 20:50:17 -0800 Jerry Hancock wrote: > I read up on the GPS L1/L2 and I think there is an L5. for your rainy Sunday reading: http://www.navipedia.net/index.php/GPS_Signal_Plan http://www.navipedia.net/index.php/Galileo_Signal_Plan

Re: [time-nuts] H-Maser drift (was: Why discipline Rubidium oscillator?)

Corby can most likely answer some of these questions, since he also has a maser and does maintain it. He is right now most likely still asleep, California time. Bert Kehren In a message dated 11/21/2017 9:25:30 A.M. Eastern Standard Time, att...@kinali.ch writes: On Tue, 21 Nov 2017

Re: [time-nuts] H-Maser drift (was: Why discipline Rubidium oscillator?)

Hi, Dana. > What does 'EFOS' mean? I hadn't heard the term before. EFOS was a series of masers made by Oscilloquartz in Switzerland, there is a little information on my website www.efos3.com under «about». The manuals for those masers are also available, lots of good info for the interested:

Re: [time-nuts] H-Maser drift (was: Why discipline Rubidium oscillator?)

Hi Ole, What does 'EFOS' mean? I hadn't heard the term before. I think I've heard the one-second lifetime figure before. I do hear mixed reports about where the conversion to atomic H occurs, and consider the jury to still be out on that question. I had thought that the volume of the storage

Re: [time-nuts] H-Maser drift (was: Why discipline Rubidium oscillator?)

On Tue, 21 Nov 2017 14:50:48 +0100 Attila Kinali wrote: > The source for the Hydrogen atoms is usually a heated platinum > valve (a heated plate of platinum that is thin enough that the > Hydrogen will leak through). Several people pointed out that the valve is made of

[time-nuts] Disciplining a Cs beam standard (was: Why discipline Rubidium oscillator?)

On Mon, 20 Nov 2017 20:18:18 -0500 Bob kb8tq wrote: > You can (or course) do a GPS disciplined Cs standard. That’s not easy to do, > but some are attempting it …. It is actually quite easy. You measure the satellite carrier and code phases relative to the output signal of the

Re: [time-nuts] H-Maser drift (was: Why discipline Rubidium oscillator?)

On Tue, 21 Nov 2017 15:14:59 +0100 Ole Petter Ronningen wrote: > > [...] The advantage of the platinum valve > > system is that it "generates" single atom Hydrogen, as required > > by the maser. > > Picking nits here.. It was my understanding that the splitting of

Re: [time-nuts] H-Maser drift (was: Why discipline Rubidium oscillator?)

On Tue, 21 Nov 2017 15:31:25 +0100 Ole Petter Ronningen wrote: > > Hehe.. Yes. It's "small" compared to the cavity. Depending on the > > exact cavity construction, the storage space can be as small as > > a tenth of the total cavity volume. > > Thats interesting, I would

[time-nuts] H-Maser drift (was: Why discipline Rubidium oscillator?)

On Tue, 21 Nov 2017 04:24:51 -0600 Dana Whitlow wrote: > This is an active maser, meaning a self-sustaining oscillator whose gain > medium > was a volume of hydrogen atoms (at low pressure) maintained in a population- > inverted state by squirting a thin stream of

Re: [time-nuts] H-Maser drift (was: Why discipline Rubidium oscillator?)

> > > > 4.5 liters in EFOS type masers - so not *that* small. I believe other > > masers are the same order of magnitude. > > Hehe.. Yes. It's "small" compared to the cavity. Depending on the > exact cavity construction, the storage space can be as small as > a tenth of the total cavity volume.

Re: [time-nuts] Why discipline Rubidium oscillator?

Hi Cesiums (that may be on their last legs or maybe not) are pretty common in the market. Prices vary, but generally are < $4,000. Bought new they are in the $70,000 range. Masers show up much less often. Price wise … that depends. The cheapest working unit I have heard of was in the $30,000

Re: [time-nuts] HP5065A C-field mods and optical unit mods

Hi Charles, what you refer is the resistance relation referred to the LM299 source around 14VDc but you have to consider the tuning range of the pot, in the original HP5065A is 2E10-9. Of course, it depends on the setting value of the variable resistance, but you have to consider a

Re: [time-nuts] H-Maser drift (was: Why discipline Rubidium oscillator?)

On Tue, Nov 21, 2017 at 2:50 PM, Attila Kinali wrote: > [...] The advantage of the platinum valve > system is that it "generates" single atom Hydrogen, as required > by the maser. Picking nits here.. It was my understanding that the splitting of molecular hydrogen into atomic

[time-nuts] Programmed Test Sources PTS-x10

The Programmed Test Sources PTS-x10 manual is available from Mediafire http://www.mediafire.com/file/ak193b371mbb3vc/PTS_X10.pdf ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to

Re: [time-nuts] H-maser drift

There seem to be a lot of misunderstandings about H-masers. To set the record straight note: 1. The flow of hydrogen is generally controlled using a palladium membrane, though a palladium-silver alloy is to be preferred because it is less likely to crack. Only hydrogen will diffuse through the

Re: [time-nuts] HP5065A C-field mods and optical unit mods

Luciano wrote: what you refer is the resistance relation referred to the LM299 source around 14VDc but you have to consider the tuning range of the pot, in the original HP5065A is 2E10-9. Of course, it depends on the setting value of the variable resistance, but you have to

Re: [time-nuts] HP5065A C-field mods and optical unit mods

What is the effect of the C-field coil dimension tempco? At some point this will surely dominate overthe coil current tempco. Bruce > > On 22 November 2017 at 09:16 Charles Steinmetz > wrote: > > Luciano wrote: > > > > > > what you refer is

Re: [time-nuts] H-maser drift

Thank you John. That was most informative. dana On Tue, Nov 21, 2017 at 2:26 PM, John Ponsonby wrote: > There seem to be a lot of misunderstandings about H-masers. To set the > record straight note: > 1. The flow of hydrogen is generally controlled using a palladium >

Re: [time-nuts] HP5065A C-field mods and optical unit mods

In message <1159987519.5777361.1511296831...@webmail.xtra.co.nz>, Bruce Griffit hs writes: >What is the effect of the C-field coil dimension tempco? I have not been able to measure it. The C-coil is located thermally close to the temperature controlled parts of the physics package. --

Re: [time-nuts] H-maser drift

Yes, Thank you John. Enjoyable reading and informative. Dave W6TE Sent from Mail for Windows 10 From: time-nuts on behalf of John Ponsonby Sent: