Re: [time-nuts] True Time Nut Mission: NASA's Deep Space Atomic Clock (DSAC)

After the successful Falcon Heavy launch earlier this week, it appears that the Deep Space Atomic Clock (DSAC) is now scheduled to go up in June 2018 on a Falcon Heavy carrying the US Air Force STP-2 test payloads.

[time-nuts] Looking for Datum TymServe 2000 (TS2000) manual

Hello Time-Nuts, After a very long journey trying to figure out the correct cable configuration between the AcuTime GPS antenna (receiver) and a Datum TS2000 I now have it working. Now I am in need of a manual so I can talk over the serial port. The protocol is apparently not the same as the

Re: [time-nuts] Vanguard TCXO

On 2/8/18 11:49 AM, Mark Goldberg wrote: On Thu, Feb 8, 2018 at 10:51 AM, jimlux wrote: On 2/8/18 5:34 AM, Mark Goldberg wrote: What is the phase noise like on the cheap TCXO?Vectron VT-702 (the first one in the list online) -99 at 10Hz -123 at 100Hz -143 at 1kHz

Re: [time-nuts] Receiving the MSF time signal on cheap radio modules

> Hal Murray wrote: > If the two signals are not encoded identically, there should be an > interesting signal when one of the transmitters is off and the other is on. > Has anybody looked for that sort of pattern? > Is there a map of the dead spots? Any time-nuts live in/near one? Yes. Here

Re: [time-nuts] Vanguard TCXO

On Thu, Feb 8, 2018 at 10:51 AM, jimlux wrote: > On 2/8/18 5:34 AM, Mark Goldberg wrote: > >> What is the phase noise like on the cheap TCXO?Vectron >> > > > VT-702 (the first one in the list online) > -99 at 10Hz > -123 at 100Hz > -143 at 1kHz > > going to Mouser and

[time-nuts] Fast 30ps risetime pulse generator with SMA/2.92mm output

I have promised a few people here to let them know when the microwave / SMA connector version of my fast risetime pulser is available. It is available now: http://www.leobodnar.com/shop/index.php?main_page=index=124 For those not familiar with what it does - this is a pulse train generator with

Re: [time-nuts] Vanguard TCXO

On 2/8/18 5:34 AM, Mark Goldberg wrote: What is the phase noise like on the cheap TCXO? Being on frequency is far from the only characteristic that matters. I did some research on cheap TCXOs for Kenwood radios and found truly awful phase noise and lots of spurs above and below the oscillator

[time-nuts] Looking for WJ YIG Tuned GaAs Osc. (YTO)

Hello, fellow time-nuts, hope all is well with all of you, I am looking for a Watkins-Johnson WJ-5008-104 YIG Tuned GaAs Oscillator 8.00 to 12.40 GHz or a Stoddart-Singer-Ailtech-Carnel Labs NM-67 Microwave Receiver for parts only. If you can help or send me any leads the contact email is

Re: [time-nuts] Receiving the MSF time signal on cheap radio modules

Challenge accepted. This graph is probably not too useful, for the simple reason that when the receiver is spitting out mostly noise, the averages are going to be massively affected. [image: Inline images 1] On 7 February 2018 at 01:03, Hal Murray wrote: > >

Re: [time-nuts] Vanguard TCXO

What is the phase noise like on the cheap TCXO? Being on frequency is far from the only characteristic that matters. I did some research on cheap TCXOs for Kenwood radios and found truly awful phase noise and lots of spurs above and below the oscillator frequency. I don't know if these

Re: [time-nuts] Does a frequency counter locked to GPS need to "warm up"?

Exactly what I have run into. Some systems lock an internal reference to to the incoming system. So that oven has to come up to temp. Then the trigger and interpolators need to warm up and stabilize. So the really right answer is what accuracy are you looking for? Because what I mention above may

Re: [time-nuts] Does a frequency counter locked to GPS need to "warm up"?

Hi, Well, actually there is two methods: 1) Switch reference clock - a switch or mux changes which clock is being used. 2) Lock internal reference to external reference - a PLL lock of the internal reference to the external reference is enabled. For both, the counter core may need to heat up.

Re: [time-nuts] Does a frequency counter locked to GPS need to "warm up"?

Yes, You have removed the reference from the warmup but the input circuits still need time to reach thermal equilibrium for most accurate results On Feb 8, 2018, at 3:34 AM, Azelio Boriani wrote: No warmup needed if the counter switches to the external reference.

Re: [time-nuts] Does a frequency counter locked to GPS need to "warm up"?

Hi It depends a *lot* on the frequency counter. An old style “just count the number of edges” device should be good to go pretty fast. One of the “fry an egg on it” interpolating counters that get into the 20 ps range may well need some time to stabilize. If you are doing ADEV runs, a couple

Re: [time-nuts] Anyone have experience with this antenna?

On Wed, Feb 07, 2018 at 03:07:24PM +, Poul-Henning Kamp wrote: > > In message <875e4bc6-32c3-4724-afcd-086553ae5...@n1k.org>, Bob kb8tq writes: > > >Water wise, one might note the large piles of snow sitting on my antennas at > >the moment. Yes, I > >could go knock it off, but

[time-nuts] Vanguard TCXO

Hello All, This is for the medium-precision nuts amongst us. I have invested £14.50 in one of these Vanguard 0.1ppm TCXO's to pimp my Siglent FG which has a footprint for it. It is its internal ref at 25 MHz. The swapping-in was simple to do and the FG works fine with it. Since it has a

Re: [time-nuts] Does a frequency counter locked to GPS need to "warm up"?

Hi, On 02/08/2018 08:33 AM, Chris Wilson wrote: > > > 08/02/2018 07:31 > > Does a frequency counter connected to a permanently running (Trimble > Thunderbolt) GPS > disciplined frequency standard need to warm up after switch on before > readings settle? > Just curious, thanks. >

Re: [time-nuts] Does a frequency counter locked to GPS need to "warm up"?

No warmup needed if the counter switches to the external reference. If the counter uses the external reference to lock the internal one then it is better to wait until the internal one is stable, maybe the counter has a standby mode where it appears powered off but the internal reference is active