Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Hi Your budget is going to make things tough. A Thunderbolt needs a triple supply (+12, -12, and +5) to operate. It also needs a GPS antenna of some sort. The Rubidiums all need a supply and a heat sink. Some of them like the FRS-A need unusual connectors. They all need to be operated continuously to get the best accuracy. That makes powering them with a shared lab supply impractical. The Thunderbolt is accurate as a stand alone device because it uses GPS. The rubidiums are all fairly accurate by design, but they would need to be calibrated against something else to be as accurate as the Thunderbolt. Simple look at it: If you need ~ 3x10-9 accuracy, then the rubidiums are all fine. If you need < 2 x10-10 accuracy, then the Thunderbolt is your only choice. In between those two limits, it depends on a lot of details like how long between calibrations, environment (like temperature), and sources of calibration. Even at the limits I've mentioned, what you are calibrating might impact the choice. If you have a spare triple output supply already, Then the Thunderbolt is inside your budget. If you do not have a supply, you probably can pick up the pieces on individual auctions with some luck and patience. If you go with a rubidium, look for a dealer who will include the connectors for the device. One last point: The Thunderbolt *probably* will run for a very long time. The rubidiums may also run for a long time, or they may die 5 or 10 years from now due to lamp wear out. Lots to think about. Bob On Dec 27, 2009, at 4:12 PM, Giuseppe Marullo wrote: > Hi all, > just subscribed, I would like a quick advice on a 10MHz reference for > calibrating my instruments and for fun. In particular, I would like to know > if you could give me advice on EFRATOM FRS-A,FRS-C, DATUM LPRO-101, > Thunderbolt and such. > > I would prefer a GPSDO (like the Thunderbolt), but budget is very tight > (about 100EUR), so I am searching old surplus stuff on Ebay. > > Some examples: > > http://cgi.ebay.com/Thunderbolt-PRECISION-GPS-10mhz-FREQUENCY-TIME-Standard_W0QQitemZ270504461779QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item3efb5285d3 > > http://cgi.ebay.com/EFRATOM-10MHZ-LPRO-101-Rubidium-Frequency-Standard_W0QQitemZ270504461780QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item3efb5285d4 > > Any caveat, anything I should ask to the seller? Minimal fw version for the > Thunderbolt (2.2 is okay)? > > Thanks in advance, > > Giuseppe > > PS: I am in Italy > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
And started down the dark path you have. You will not have to wait long before you completely succumb to the dark side. Jim Palfreyman 2009/12/28 Bob Camp : > Hi > > Your budget is going to make things tough. > > A Thunderbolt needs a triple supply (+12, -12, and +5) to operate. It also > needs a GPS antenna of some sort. > > The Rubidiums all need a supply and a heat sink. Some of them like the FRS-A > need unusual connectors. > > They all need to be operated continuously to get the best accuracy. That > makes powering them with a shared lab supply impractical. > > The Thunderbolt is accurate as a stand alone device because it uses GPS. The > rubidiums are all fairly accurate by design, but they would need to be > calibrated against something else to be as accurate as the Thunderbolt. > > Simple look at it: > > If you need ~ 3x10-9 accuracy, then the rubidiums are all fine. > > If you need < 2 x10-10 accuracy, then the Thunderbolt is your only choice. > > In between those two limits, it depends on a lot of details like how long > between calibrations, environment (like temperature), and sources of > calibration. Even at the limits I've mentioned, what you are calibrating > might impact the choice. > > If you have a spare triple output supply already, Then the Thunderbolt is > inside your budget. If you do not have a supply, you probably can pick up the > pieces on individual auctions with some luck and patience. If you go with a > rubidium, look for a dealer who will include the connectors for the device. > > One last point: The Thunderbolt *probably* will run for a very long time. The > rubidiums may also run for a long time, or they may die 5 or 10 years from > now due to lamp wear out. > > Lots to think about. > > Bob > > > On Dec 27, 2009, at 4:12 PM, Giuseppe Marullo wrote: > >> Hi all, >> just subscribed, I would like a quick advice on a 10MHz reference for >> calibrating my instruments and for fun. In particular, I would like to know >> if you could give me advice on EFRATOM FRS-A,FRS-C, DATUM LPRO-101, >> Thunderbolt and such. >> >> I would prefer a GPSDO (like the Thunderbolt), but budget is very tight >> (about 100EUR), so I am searching old surplus stuff on Ebay. >> >> Some examples: >> >> http://cgi.ebay.com/Thunderbolt-PRECISION-GPS-10mhz-FREQUENCY-TIME-Standard_W0QQitemZ270504461779QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item3efb5285d3 >> >> http://cgi.ebay.com/EFRATOM-10MHZ-LPRO-101-Rubidium-Frequency-Standard_W0QQitemZ270504461780QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item3efb5285d4 >> >> Any caveat, anything I should ask to the seller? Minimal fw version for the >> Thunderbolt (2.2 is okay)? >> >> Thanks in advance, >> >> Giuseppe >> >> PS: I am in Italy >> >> ___ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Thanks a lot to all for your quick answer. Rubinium should be good for my needs, but buying it surplus makes me think I could get something very used (and abused) and it does not have the self correcting thing thunderbolt has. GPSDO gives me also the time, maybe with a supercool LCD display. A Thunderbolt needs a triple supply (+12, -12, and +5) to operate. It also needs a GPS antenna of some sort. Do you know exactly the power requirement? On Ebay I read 15W then few mA on each branch (board only). Something is not clear to me. The dark side of the noon already embraced I have Giuseppe PS: I am experiencing mail problems for the first time in many years, please anyone willing to contact me directly do cc copy also this other email address: giuseppe.maru...@iname.com while my ISP gathers back all the bits they lost (2 days of emails vanished from my IMAP account under my eyes, literally) ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
giuse...@marullo.it said: > Do you know exactly the power requirement? On Ebay I read 15W then few > mA on each branch (board only). Something is not clear to me. http://www.leapsecond.com/pages/tbolt/power.htm Lots more Thunderbolt info here: http://www.leapsecond.com/pages/tapr-tbolt/ -- These are my opinions, not necessarily my employer's. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Hi Giuseppe, I think you would be better served with the Thunderbolt as it is both a GPS and an oscillator, that is it is a GPSDO. Last I remember, an eBay user "Flukel" (the last character is a lower case "L") was spoken of, on this list, as being a reliable Chinese vendor. He had oscillators, Rubidiums and Thunderbolts. That said, a power supply is easy to construct from many other dead chasis parts and if needed the regulator chips are pretty cheap (well here in the USA anyway). If you do go that way and have trouble scrounging some parts for the power suppply, perhaps some of us here can help with that. BillWB6BNQ Giuseppe Marullo wrote: > Thanks a lot to all for your quick answer. > > Rubinium should be good for my needs, but buying it surplus makes me > think I could get something very used (and abused) and it does not have > the self correcting thing thunderbolt has. > GPSDO gives me also the time, maybe with a supercool LCD display. > > >A Thunderbolt needs a triple supply (+12, -12, and +5) to operate. It also > >needs a GPS antenna of some sort. > Do you know exactly the power requirement? On Ebay I read 15W then few mA on > each branch (board only). Something is not clear to me. > > The dark side of the noon already embraced I have > > Giuseppe > > PS: I am experiencing mail problems for the first time in many years, > please anyone willing to contact me directly do cc copy also this other > email address: giuseppe.maru...@iname.com while my ISP gathers back all > the bits they lost (2 days of emails vanished from my IMAP account under > my eyes, literally) > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Hi The simple answer on the supply is that there are a couple of answers. Very little current is pulled from the -12 supply. I can not imagine a supply that would not keep up with the -12 requirement. The +12 supply mainly runs the OCXO in the unit. Since it's running an oven, the power will drop off after warmup. It will also be lower at higher temperatures. Depending on exactly which OCXO you get in your unit, the power may be a little higher or a little lower. A 5V supply that can furnish 300 ma should be adequate. All of the supplies needed *could* be pulled off of a typical desk top PC power supply. If you do go that way, be sure to put some simple RF filtering in the supply leads. The unit it's self has a fairly basic case. Enclosing even in a simple pine box should improve it's performance. It would also protect the leads from getting damaged in use. The enclosure does not need to be elaborate. You should be able to make it for free from scrap materials. I have bought Thunderbolts from several dealers on eBay over the last month. All of them seem to be supplying the same product (same date codes, and firmware). They all seem to be from 2003 or 2004. Some dealers ship faster than others, some include a HF power splitter, some include a power connector. I have not had any of the units on power long enough to know if some are actually better than others. Good Luck! Bob On Dec 27, 2009, at 7:56 PM, Giuseppe Marullo wrote: > Thanks a lot to all for your quick answer. > > Rubinium should be good for my needs, but buying it surplus makes me think I > could get something very used (and abused) and it does not have the self > correcting thing thunderbolt has. > GPSDO gives me also the time, maybe with a supercool LCD display. > >> A Thunderbolt needs a triple supply (+12, -12, and +5) to operate. It also >> needs a GPS antenna of some sort. > Do you know exactly the power requirement? On Ebay I read 15W then few mA on > each branch (board only). Something is not clear to me. > > > The dark side of the noon already embraced I have > > Giuseppe > > PS: I am experiencing mail problems for the first time in many years, please > anyone willing to contact me directly do cc copy also this other email > address: giuseppe.maru...@iname.com while my ISP gathers back all the bits > they lost (2 days of emails vanished from my IMAP account under my eyes, > literally) > > > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Hi Giuseppe,
Welcome to the group.
If you are already happy constructing equipment and have basic test gear
('scope, DMM) and a small budget, I'd suggest a timing GPS as a starting point.
While a Thunderbolt will give most of what you want, it is more expensive. A
Timing version or Motorola's Oncore <(ebay item 300355981024 from flukel for
instance) will give you an accurate 1 pulse per second output (you also need a
power supply antenna and a PC). This and a 'scope will allow you to calibrate
other instruments and a oven controlled crystal oscillator. A GPS based
solution (including Thunderbolt) will give you good confidence of accuracy.
Just buying a surplus Rubidium could result in you adjusting all your
instruments to the wrong frequency! Like many of these decisions, it's a
balance between time and money, with a lesser input from your capabilities and
existing equipment.
Robert G8RPI.
--- On Mon, 28/12/09, Giuseppe Marullo wrote:
From: Giuseppe Marullo
Subject: Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
To: "Discussion of precise time and frequency measurement"
Date: Monday, 28 December, 2009, 0:56
Thanks a lot to all for your quick answer.
Rubinium should be good for my needs, but buying it surplus makes me think I
could get something very used (and abused) and it does not have the self
correcting thing thunderbolt has.
GPSDO gives me also the time, maybe with a supercool LCD display.
> A Thunderbolt needs a triple supply (+12, -12, and +5) to operate. It also
> needs a GPS antenna of some sort.
Do you know exactly the power requirement? On Ebay I read 15W then few mA on
each branch (board only). Something is not clear to me.
The dark side of the noon already embraced I have
Giuseppe
PS: I am experiencing mail problems for the first time in many years, please
anyone willing to contact me directly do cc copy also this other email address:
giuseppe.maru...@iname.com while my ISP gathers back all the bits they lost (2
days of emails vanished from my IMAP account under my eyes, literally)
___
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
___
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Giuseppe Marullo wrote: Hi all, just subscribed, I would like a quick advice on a 10MHz reference for calibrating my instruments and for fun. In particular, I would like to know if you could give me advice on EFRATOM FRS-A,FRS-C, DATUM LPRO-101, Thunderbolt and such. I would prefer a GPSDO (like the Thunderbolt), but budget is very tight (about 100EUR), so I am searching old surplus stuff on Ebay. A timing GPS receiver with a built-in 10MHz oscillator would fit your budget nicely. The Navsync CW12-TIM looks like the obvious choice. You would need the CW12-TIM module, a 3.3V DC supply and a suitable aerial/antenna. Power consumption is well below 1W. It has a 1PPS output with 30ns RMS accuracy and a NCO output with a default output frequency of 10MHz. http://www.navsync.com/docs/CW12-TIM_DS.pdf I paid just over Eur50 for mine last year when the Euro was very strong against foreign currencies. -- Linux 2.6.30 ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Hi Robert,
Will the Motorola that You have mentioned give a 10.00 MHz output standard.
Thank You
Best regards,
Sal C. Cornacchia
Electronic RF Microwave Engineer (Ret.)
From: Robert Atkinson
To: Discussion of precise time and frequency measurement
Cc: giuseppe.maru...@iname.com
Sent: Mon, December 28, 2009 5:14:49 AM
Subject: Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Hi Giuseppe,
Welcome to the group.
If you are already happy constructing equipment and have basic test gear
('scope, DMM) and a small budget, I'd suggest a timing GPS as a starting point.
While a Thunderbolt will give most of what you want, it is more expensive. A
Timing version or Motorola's Oncore <(ebay item 300355981024 from flukel for
instance) will give you an accurate 1 pulse per second output (you also need a
power supply antenna and a PC). This and a 'scope will allow you to calibrate
other instruments and a oven controlled crystal oscillator. A GPS based
solution (including Thunderbolt) will give you good confidence of accuracy.
Just buying a surplus Rubidium could result in you adjusting all your
instruments to the wrong frequency! Like many of these decisions, it's a
balance between time and money, with a lesser input from your capabilities and
existing equipment.
Robert G8RPI.
--- On Mon, 28/12/09, Giuseppe Marullo wrote:
From: Giuseppe Marullo
Subject: Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
To: "Discussion of precise time and frequency measurement"
Date: Monday, 28 December, 2009, 0:56
Thanks a lot to all for your quick answer.
Rubinium should be good for my needs, but buying it surplus makes me think I
could get something very used (and abused) and it does not have the self
correcting thing thunderbolt has.
GPSDO gives me also the time, maybe with a supercool LCD display.
> A Thunderbolt needs a triple supply (+12, -12, and +5) to operate. It also
> needs a GPS antenna of some sort.
Do you know exactly the power requirement? On Ebay I read 15W then few mA on
each branch (board only). Something is not clear to me.
The dark side of the noon already embraced I have
Giuseppe
PS: I am experiencing mail problems for the first time in many years, please
anyone willing to contact me directly do cc copy also this other email address:
giuseppe.maru...@iname.com while my ISP gathers back all the bits they lost (2
days of emails vanished from my IMAP account under my eyes, literally)
___
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
___
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To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
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To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Robert, Welcome to the group. Thank you and all the others, you are giving me a lot of informations. BTW, my provider retrieved my emails so I am fully operational (at least I hope). while I did not originally envision building this kind of equipment, I could do it while it lies well within the digital domain, I have some test gear (frequency counter, DMM, analog scope, BF frequency generator, LA and some FPGAs with 100+Msamples ADC) but...I will have to trust it so I am back at square one, until I have a reliable source... I would like a GPSDO, possibly ready to run, then I will start building something that I could actually check against the GPSDO. Maybe a GPSDO myself, who knows...wondering if this could be done all digital, without using a DAC, without using a driving voltage for a OCXO. Giuseppe ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Does the factory sell direct in small quantities ? 73, Dick, W1KSZ -Original Message- >From: Eamon Skelton >Sent: Dec 28, 2009 6:15 AM >To: Discussion of precise time and frequency measurement >Subject: Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference > >Giuseppe Marullo wrote: >> Hi all, >> just subscribed, I would like a quick advice on a 10MHz reference for >> calibrating my instruments and for fun. In particular, I would like to >> know if you could give me advice on EFRATOM FRS-A,FRS-C, DATUM LPRO-101, >> Thunderbolt and such. >> >> I would prefer a GPSDO (like the Thunderbolt), but budget is very tight >> (about 100EUR), so I am searching old surplus stuff on Ebay. > >A timing GPS receiver with a built-in 10MHz oscillator would fit >your budget nicely. The Navsync CW12-TIM looks like the obvious >choice. You would need the CW12-TIM module, a 3.3V DC supply and >a suitable aerial/antenna. Power consumption is well below 1W. >It has a 1PPS output with 30ns RMS accuracy and a NCO output >with a default output frequency of 10MHz. >http://www.navsync.com/docs/CW12-TIM_DS.pdf > >I paid just over Eur50 for mine last year when the Euro was very >strong against foreign currencies. > >-- >Linux 2.6.30 > > >___ >time-nuts mailing list -- time-nuts@febo.com >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
I was wondering the same myself and found they are sold online at: http://secure.conwin.com/cgi-bin/store/cp-app.cgi?usr=51H4350135&rnd=7294697&rrc=N&affl=&cip=92.132.242.176&act=&aff=&pg=cat&ref=navsync&catstr= - Original Message - From: "Richard W. Solomon" To: "Discussion of precise time and frequency measurement" Sent: Monday, December 28, 2009 4:49 PM Subject: Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference Does the factory sell direct in small quantities ? 73, Dick, W1KSZ -Original Message- From: Eamon Skelton Sent: Dec 28, 2009 6:15 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference Giuseppe Marullo wrote: Hi all, just subscribed, I would like a quick advice on a 10MHz reference for calibrating my instruments and for fun. In particular, I would like to know if you could give me advice on EFRATOM FRS-A,FRS-C, DATUM LPRO-101, Thunderbolt and such. I would prefer a GPSDO (like the Thunderbolt), but budget is very tight (about 100EUR), so I am searching old surplus stuff on Ebay. A timing GPS receiver with a built-in 10MHz oscillator would fit your budget nicely. The Navsync CW12-TIM looks like the obvious choice. You would need the CW12-TIM module, a 3.3V DC supply and a suitable aerial/antenna. Power consumption is well below 1W. It has a 1PPS output with 30ns RMS accuracy and a NCO output with a default output frequency of 10MHz. http://www.navsync.com/docs/CW12-TIM_DS.pdf I paid just over Eur50 for mine last year when the Euro was very strong against foreign currencies. -- Linux 2.6.30 ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Richard W. Solomon wrote: Does the factory sell direct in small quantities ? 73, Dick, W1KSZ I don't think so. I live in Cork, Ireland. Navsync are in Shannon about 70 miles from here. I ordered my CW12-TIM from Cutter Electronics in Australia. As they were out of stock at the time, I had to wait for a couple of weeks, while Navsync shipped them 20,000 miles from Ireland to Australia and back again :-) -- Linux 2.6.30 ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Hi Sal,
No it does not have a 10MHz output. However to calibrate an oscillator that is
very close to 10MHz you can use the 1PPS output to adjust it exactly. Trigger a
'scope with the 1PPS while monitoring the 10MHz, adjust the oscillator for
minimum drift across the screen.
Robert.
--- On Mon, 28/12/09, SAL CORNACCHIA wrote:
From: SAL CORNACCHIA
Subject: Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
To: "Discussion of precise time and frequency measurement"
Date: Monday, 28 December, 2009, 15:32
Hi Robert,
Will the Motorola that You have mentioned give a 10.00 MHz output standard.
Thank You
Best regards,
Sal C. Cornacchia
Electronic RF Microwave Engineer (Ret.)
From: Robert Atkinson
To: Discussion of precise time and frequency measurement
Cc: giuseppe.maru...@iname.com
Sent: Mon, December 28, 2009 5:14:49 AM
Subject: Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Hi Giuseppe,
Welcome to the group.
If you are already happy constructing equipment and have basic test gear
('scope, DMM) and a small budget, I'd suggest a timing GPS as a starting point.
While a Thunderbolt will give most of what you want, it is more expensive. A
Timing version or Motorola's Oncore <(ebay item 300355981024 from flukel for
instance) will give you an accurate 1 pulse per second output (you also need a
power supply antenna and a PC). This and a 'scope will allow you to calibrate
other instruments and a oven controlled crystal oscillator. A GPS based
solution (including Thunderbolt) will give you good confidence of accuracy.
Just buying a surplus Rubidium could result in you adjusting all your
instruments to the wrong frequency! Like many of these decisions, it's a
balance between time and money, with a lesser input from your capabilities and
existing equipment.
Robert G8RPI.
--- On Mon, 28/12/09, Giuseppe Marullo wrote:
From: Giuseppe Marullo
Subject: Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
To: "Discussion of precise time and frequency measurement"
Date: Monday, 28 December, 2009, 0:56
Thanks a lot to all for your quick answer.
Rubinium should be good for my needs, but buying it surplus makes me think I
could get something very used (and abused) and it does not have the self
correcting thing thunderbolt has.
GPSDO gives me also the time, maybe with a supercool LCD display.
> A Thunderbolt needs a triple supply (+12, -12, and +5) to operate. It also
> needs a GPS antenna of some sort.
Do you know exactly the power requirement? On Ebay I read 15W then few mA on
each branch (board only). Something is not clear to me.
The dark side of the noon already embraced I have
Giuseppe
PS: I am experiencing mail problems for the first time in many years, please
anyone willing to contact me directly do cc copy also this other email address:
giuseppe.maru...@iname.com while my ISP gathers back all the bits they lost (2
days of emails vanished from my IMAP account under my eyes, literally)
___
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
___
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
___
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
___
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To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Maybe a GPSDO myself, who knows...wondering if this could be done all digital, without using a DAC, without using a driving voltage for a OCXO. Giuseppe Symmetricom made a OXCO that had the DAC built-in so it was controlled by a digital interface. But it is hard to find, seen them on ebay but not now. Stanley ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Thank You Robert for the quick response.
Best regards,
Sal C. Cornacchia
Electronic RF Microwave Engineer (Ret.)
From: Robert Atkinson
To: Discussion of precise time and frequency measurement
Sent: Mon, December 28, 2009 12:07:21 PM
Subject: Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Hi Sal,
No it does not have a 10MHz output. However to calibrate an oscillator that is
very close to 10MHz you can use the 1PPS output to adjust it exactly. Trigger a
'scope with the 1PPS while monitoring the 10MHz, adjust the oscillator for
minimum drift across the screen.
Robert.
--- On Mon, 28/12/09, SAL CORNACCHIA wrote:
From: SAL CORNACCHIA
Subject: Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
To: "Discussion of precise time and frequency measurement"
Date: Monday, 28 December, 2009, 15:32
Hi Robert,
Will the Motorola that You have mentioned give a 10.00 MHz output standard.
Thank You
Best regards,
Sal C. Cornacchia
Electronic RF Microwave Engineer (Ret.)
From: Robert Atkinson
To: Discussion of precise time and frequency measurement
Cc: giuseppe.maru...@iname.com
Sent: Mon, December 28, 2009 5:14:49 AM
Subject: Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Hi Giuseppe,
Welcome to the group.
If you are already happy constructing equipment and have basic test gear
('scope, DMM) and a small budget, I'd suggest a timing GPS as a starting point.
While a Thunderbolt will give most of what you want, it is more expensive. A
Timing version or Motorola's Oncore <(ebay item 300355981024 from flukel for
instance) will give you an accurate 1 pulse per second output (you also need a
power supply antenna and a PC). This and a 'scope will allow you to calibrate
other instruments and a oven controlled crystal oscillator. A GPS based
solution (including Thunderbolt) will give you good confidence of accuracy.
Just buying a surplus Rubidium could result in you adjusting all your
instruments to the wrong frequency! Like many of these decisions, it's a
balance between time and money, with a lesser input from your capabilities and
existing equipment.
Robert G8RPI.
--- On Mon, 28/12/09, Giuseppe Marullo wrote:
From: Giuseppe Marullo
Subject: Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
To: "Discussion of precise time and frequency measurement"
Date: Monday, 28 December, 2009, 0:56
Thanks a lot to all for your quick answer.
Rubinium should be good for my needs, but buying it surplus makes me think I
could get something very used (and abused) and it does not have the self
correcting thing thunderbolt has.
GPSDO gives me also the time, maybe with a supercool LCD display.
> A Thunderbolt needs a triple supply (+12, -12, and +5) to operate. It also
> needs a GPS antenna of some sort.
Do you know exactly the power requirement? On Ebay I read 15W then few mA on
each branch (board only). Something is not clear to me.
The dark side of the noon already embraced I have
Giuseppe
PS: I am experiencing mail problems for the first time in many years, please
anyone willing to contact me directly do cc copy also this other email address:
giuseppe.maru...@iname.com while my ISP gathers back all the bits they lost (2
days of emails vanished from my IMAP account under my eyes, literally)
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Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
> Does the factory sell direct in small quantities ? >From here (California), googling for >Navsync CW12-TIM< finds: http://www.semiconductorstore.com/pages/asp/supplier.asp?pl=0138&gclid=CL_G5ar W-Z4CFU1M5Qod1XNWLA (Sorry for the line wrap.) -- These are my opinions, not necessarily my employer's. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
One thing to keep in mind about the CW-12 is that the version they're selling now runs NMEA software only - which means no TRAIM functionality. If you do manage to find the Motorola version to get TRAIM, you lose the ability to change the oscillator frequency. It's fixed at 10 MHz. I bought my CW-12 a year or two ago from Semiconductorstore.com and they said it was the Motorola load. It wasn't. They did manage to get me a copy of the program to flash it to the Motorola load. That's when I realized I couldn't change the frequency. Oh, well. Ed - Original Message - From: Hal Murray Date: Monday, December 28, 2009 11:44 am Subject: Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference > > > Does the factory sell direct in small quantities ? > > From here (California), googling for >Navsync CW12-TIM< finds: > http://www.semiconductorstore.com/pages/asp/supplier.asp?pl=0138&gclid=CL_G5ar > W-Z4CFU1M5Qod1XNWLA > (Sorry for the line wrap.) > > > -- > These are my opinions, not necessarily my employer's. I hate spam. > > > > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi- > bin/mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Giuseppe Marullo wrote: Robert, Welcome to the group. Thank you and all the others, you are giving me a lot of informations. BTW, my provider retrieved my emails so I am fully operational (at least I hope). while I did not originally envision building this kind of equipment, I could do it while it lies well within the digital domain, I have some test gear (frequency counter, DMM, analog scope, BF frequency generator, LA and some FPGAs with 100+Msamples ADC) but...I will have to trust it so I am back at square one, until I have a reliable source... I would like a GPSDO, possibly ready to run, then I will start building something that I could actually check against the GPSDO. Maybe a GPSDO myself, who knows...wondering if this could be done all digital, without using a DAC, without using a driving voltage for a OCXO. Giuseppe Giuseppe One can use a DDS or equivalent phase continuous high resolution sysnthesizer to produce a corrected output frequency using the OCXO frequency as an input, however the DDS itself uses a DAC and you will probably need to use a few cascaded mix and divide stages to reduce the spur amplitude to an acceptable level. This has the advantage that one can use an OCXO that either doesnt have an EFC input or one that has drifted beyond the adjustment range (via EFC and/or mechanical trimmer) but is otherwise quiet and stable. Bruce ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Semiconductorstore.com also have the CW25-TIM at a cheaper price ($64 vs $89) and it is more sensitive, so can possibly work indoors. They both, apparently, use the same NavSync chips, so does the '25 have disadvantages I haven't spotted? Peter 2009/12/28 Hal Murray : > >> Does the factory sell direct in small quantities ? > > From here (California), googling for >Navsync CW12-TIM< finds: > http://www.semiconductorstore.com/pages/asp/supplier.asp?pl=0138&gclid=CL_G5ar > W-Z4CFU1M5Qod1XNWLA > (Sorry for the line wrap.) ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
The CW-12 consists of the CW-25 mounted on a circuit board with some glue logic, connectors, etc. The CW-25 itself is the surface-mount module in the middle of the CW-12. Compare the pictures - you'll see what I mean. Both units are listed as having a tracking sensitivity of -155 dbm. I don't know what you mean when you say that the CW-25 is more sensitive. By the way, the CW-12 works great indoors. Through a typical wood-frame construction I usually get 7 or 8 satellites with a cheap active patch antenna. With a VIC-100 timing antenna, I usually have 10 or more satellites. 1 PPS performance is also very good. Multiple measurements of 1000 periods shows a standard deviation of <5 ns with a min-max range of < 30 ns. This is without sawtooth correction because this unit doesn't support it - even with the Motorola software. Ed - Original Message - From: Peter Vince Date: Tuesday, December 29, 2009 10:21 am Subject: Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference > Semiconductorstore.com also have the CW25-TIM at a cheaper price ($64 > vs $89) and it is more sensitive, so can possibly work indoors. They > both, apparently, use the same NavSync chips, so does the '25 have > disadvantages I haven't spotted? > > Peter > > > 2009/12/28 Hal Murray : > > > >> Does the factory sell direct in small quantities ? > > > > From here (California), googling for >Navsync CW12-TIM< finds: > > > http://www.semiconductorstore.com/pages/asp/supplier.asp?pl=0138&gclid=CL_G5ar> > W-Z4CFU1M5Qod1XNWLA > > (Sorry for the line wrap.) > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi- > bin/mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Thanks Ed, yes, I hadn't looked closely enough at the pictures. The "higher sensitivity" I mentioned came from the second line of the "Features" section near the bottom of: http://www.semiconductorstore.com/cart/pc/viewPrd.asp?idproduct=41599 "Enables indoor use -173 dBW acquisition and -185 dBW tracking" although admittedly right underneath that in the "Specifications" section is does say: "Track Sensitivity: -155 dBm" A cased of "specmanship"? Peter 2009/12/29 Ed Palmer : > The CW-12 consists of the CW-25 mounted on a circuit board with some glue > logic, connectors, etc. The CW-25 itself is the surface-mount module in the > middle of the CW-12. Compare the pictures - you'll see what I mean. Both > units > are listed as having a tracking sensitivity of -155 dbm. I don't know what > you > mean when you say that the CW-25 is more sensitive. > > By the way, the CW-12 works great indoors. Through a typical wood-frame > construction I usually get 7 or 8 satellites with a cheap active patch > antenna. > With a VIC-100 timing antenna, I usually have 10 or more satellites. 1 PPS > performance is also very good. Multiple measurements of 1000 periods > shows a standard deviation of <5 ns with a min-max range of < 30 ns. This is > without sawtooth correction because this unit doesn't support it - even with > the > Motorola software. > > Ed > > - Original Message - > From: Peter Vince > Date: Tuesday, December 29, 2009 10:21 am > Subject: Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference > >> Semiconductorstore.com also have the CW25-TIM at a cheaper price ($64 >> vs $89) and it is more sensitive, so can possibly work indoors. They >> both, apparently, use the same NavSync chips, so does the '25 have >> disadvantages I haven't spotted? >> >> Peter >> >> >> 2009/12/28 Hal Murray : >> > >> >> Does the factory sell direct in small quantities ? >> > >> > From here (California), googling for >Navsync CW12-TIM< finds: >> > >> http://www.semiconductorstore.com/pages/asp/supplier.asp?pl=0138&gclid=CL_G5ar> >> W-Z4CFU1M5Qod1XNWLA >> > (Sorry for the line wrap.) >> >> ___ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi- >> bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > __ > This email has been scanned by the MessageLabs Email Security System. > For more information please visit http://www.messagelabs.com/email > __ > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
-185dBW = -155dBm so both sensitivity measures are equivalent. Bruce Peter Vince wrote: Thanks Ed, yes, I hadn't looked closely enough at the pictures. The "higher sensitivity" I mentioned came from the second line of the "Features" section near the bottom of: http://www.semiconductorstore.com/cart/pc/viewPrd.asp?idproduct=41599 "Enables indoor use -173 dBW acquisition and -185 dBW tracking" although admittedly right underneath that in the "Specifications" section is does say: "Track Sensitivity: -155 dBm" A cased of "specmanship"? Peter 2009/12/29 Ed Palmer: The CW-12 consists of the CW-25 mounted on a circuit board with some glue logic, connectors, etc. The CW-25 itself is the surface-mount module in the middle of the CW-12. Compare the pictures - you'll see what I mean. Both units are listed as having a tracking sensitivity of -155 dbm. I don't know what you mean when you say that the CW-25 is more sensitive. By the way, the CW-12 works great indoors. Through a typical wood-frame construction I usually get 7 or 8 satellites with a cheap active patch antenna. With a VIC-100 timing antenna, I usually have 10 or more satellites. 1 PPS performance is also very good. Multiple measurements of 1000 periods shows a standard deviation of<5 ns with a min-max range of< 30 ns. This is without sawtooth correction because this unit doesn't support it - even with the Motorola software. Ed - Original Message ----- From: Peter Vince Date: Tuesday, December 29, 2009 10:21 am Subject: Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference Semiconductorstore.com also have the CW25-TIM at a cheaper price ($64 vs $89) and it is more sensitive, so can possibly work indoors. They both, apparently, use the same NavSync chips, so does the '25 have disadvantages I haven't spotted? Peter 2009/12/28 Hal Murray: Does the factory sell direct in small quantities ? From here (California), googling for>Navsync CW12-TIM< finds: http://www.semiconductorstore.com/pages/asp/supplier.asp?pl=0138&gclid=CL_G5ar> W-Z4CFU1M5Qod1XNWLA (Sorry for the line wrap.) ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi- bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. __ This email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email __ ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Oh Good Lord - not paying attention to the units! Sorry guys! Peter. 2009/12/29 Bruce Griffiths : > -185dBW = -155dBm > so both sensitivity measures are equivalent. > > Bruce > > Peter Vince wrote: >> >> Thanks Ed, yes, I hadn't looked closely enough at the pictures. >> >> The "higher sensitivity" I mentioned came from the second line of the >> "Features" section near the bottom of: >> http://www.semiconductorstore.com/cart/pc/viewPrd.asp?idproduct=41599 >> >> "Enables indoor use -173 dBW acquisition and -185 dBW tracking" >> >> although admittedly right underneath that in the "Specifications" >> section is does say: >> >> "Track Sensitivity: -155 dBm" >> >> A cased of "specmanship"? >> >> Peter >> >> >> >> 2009/12/29 Ed Palmer: >> >>> >>> The CW-12 consists of the CW-25 mounted on a circuit board with some glue >>> logic, connectors, etc. The CW-25 itself is the surface-mount module in >>> the >>> middle of the CW-12. Compare the pictures - you'll see what I mean. >>> Both units >>> are listed as having a tracking sensitivity of -155 dbm. I don't know >>> what you >>> mean when you say that the CW-25 is more sensitive. >>> >>> By the way, the CW-12 works great indoors. Through a typical wood-frame >>> construction I usually get 7 or 8 satellites with a cheap active patch >>> antenna. >>> With a VIC-100 timing antenna, I usually have 10 or more satellites. 1 >>> PPS >>> performance is also very good. Multiple measurements of 1000 periods >>> shows a standard deviation of<5 ns with a min-max range of< 30 ns. This >>> is >>> without sawtooth correction because this unit doesn't support it - even >>> with the >>> Motorola software. >>> >>> Ed >>> >>> - Original Message - >>> From: Peter Vince >>> Date: Tuesday, December 29, 2009 10:21 am >>> Subject: Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference >>> >>> >>>> >>>> Semiconductorstore.com also have the CW25-TIM at a cheaper price ($64 >>>> vs $89) and it is more sensitive, so can possibly work indoors. They >>>> both, apparently, use the same NavSync chips, so does the '25 have >>>> disadvantages I haven't spotted? >>>> >>>> Peter >>>> >>>> >>>> 2009/12/28 Hal Murray: >>>> >>>>> >>>>> >>>>>> >>>>>> Does the factory sell direct in small quantities ? >>>>>> >>>>> >>>>> From here (California), googling for>Navsync CW12-TIM< finds: >>>>> >>>>> >>>> >>>> >>>> http://www.semiconductorstore.com/pages/asp/supplier.asp?pl=0138&gclid=CL_G5ar> >>>> W-Z4CFU1M5Qod1XNWLA >>>> >>>>> >>>>> (Sorry for the line wrap.) >>>>> >>>> >>>> ___ >>>> time-nuts mailing list -- time-nuts@febo.com >>>> To unsubscribe, go to https://www.febo.com/cgi- >>>> bin/mailman/listinfo/time-nuts >>>> and follow the instructions there. >>>> >>>> >>> >>> ___ >>> time-nuts mailing list -- time-nuts@febo.com >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >>> __ >>> This email has been scanned by the MessageLabs Email Security System. >>> For more information please visit http://www.messagelabs.com/email >>> __ >>> >>> >> >> ___ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> > > > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > __ > This email has been scanned by the MessageLabs Email Security System. > For more information please visit http://www.messagelabs.com/email > __ > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Bruce Griffiths wrote: -185dBW = -155dBm so both sensitivity measures are equivalent. But -185 dB(something) looks more impressive than -155 dB(something). Specsmanship... indeed. I also spoted this detail. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Timenoob - Cheap and simple 10MHz reference
Peter Vince wrote: Oh Good Lord - not paying attention to the units! Sorry guys! This is exactly what they wanted to achieve, but the good thing is that more people got to become aware of it, so something good came out of that misstake. At least something good came out of it. When something looks 30 dB better than the competition, it may be good to check the nitty gritty. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
