[time-nuts] My old new 53132A just arrived
Hi all, My first goal is to verify the frequency of my different RF sources : 4420B, some DDS, a N2PK VNA and ISOTEMP 134-10, the next step with the help of an Excel spread sheet to have some idea about their respective stability. Equipped with option 010, I would like to know how in which direction to go to calibrate my unit. The frequency of the internal time base is supposed to be stable but I have no way to know the exact frequency as the unit is an old one. So I suppose I have to calibrate the gear with an external source, for now I can suppose that my 53132A is accurate to 10-6 or +-1Hz, as it is so easy to turn the front panel adjusting screw, I am not sure about the actual precision. I can take two possible direction to improve my system with an external time base. 1. acquire a rubidium 10Mhz, put in in a box with a 24V power supply Or 2. acquire a 10Mhz GMS time unit or homebrew one with one of the numerous project that we can find. Can somebody give an advice : I have no clue to choose between the solutions, apart the power drain of the first one. Regards Loïc http://www.eai.fr ___ 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] My old new 53132A just arrived
Am 09.08.2010 14:15, schrieb Loïc MOREAU: Hi all, My first goal is to verify the frequency of my different RF sources : 4420B, some DDS, a N2PK VNA and ISOTEMP 134-10, the next step with the help of an Excel spread sheet to have some idea about their respective stability. Equipped with option 010, I would like to know how in which direction to go to calibrate my unit. The frequency of the internal time base is supposed to be stable but I have no way to know the exact frequency as the unit is an old one. So I suppose I have to calibrate the gear with an external source, for now I can suppose that my 53132A is accurate to 10-6 or +-1Hz, as it is so easy to turn the front panel adjusting screw, I am not sure about the actual precision. I can take two possible direction to improve my system with an external time base. 1. acquire a rubidium 10Mhz, put in in a box with a 24V power supply Or 2. acquire a 10Mhz GMS time unit or homebrew one with one of the numerous project that we can find. Can somebody give an advice : I have no clue to choose between the solutions, apart the power drain of the first one. Regards Loïc http://www.eai.fr Hi Loïc, it is easy if you could get a Trimble Tunderbolt with a GPS-antenna. Connect the 10 MHz out of TB to the ext. 10 MHz input of your 53132A and you will have a precise reading close to 1 E-11. After getting the counter stable running some days or a week you may then calibrate the internal ocxo comparing both oscillators. One source for a TB was TAPR. Mine does pull just about 7 W, about a third of a RbO. If you are lucky you may find a PRS10 RbO for a reasonable price, but it does need as well beeing calibrated from time to time and will be more expensive overall. Bonne chance, Arnold ___ 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] My old new 53132A just arrived
Hi If you have been reading here for a while, you know that I would recommend a Thunderbolt to just about anybody. They are cheap (for what they are) and easy to find. My first suggestion would be a TBolt. Here's another approach: Do you really need accuracy, or is stability good enough? If stability is good enough, how stable for how long? A double oven crystal oscillator, kept on power could give you 0.1 ppb / day stability and 1 ppb / month. An LPRO rubidium would do about the same day to day, but would get you to 0.01 ppb / month. Either one of them could be calibrated by a short battery powered visit to a friend who is running a TBolt or something similar. That would likely allow accuracy of 1 ppb with either device. The LPRO would hold the accuracy for year or more. The OCXO would hold it for a month or more. At the other extreme: If you want to do instantaneous accurate and stable readings to the floor of the 53132, then both approaches have some limits. The TBolt would have to be in a very stable temperature environment to get close to the level the counter is capable of. You would also need to tweak it's parameters a bit. Accuracy would (obviously) be the issue with the free running sources. At the Time Nuts extreme: You really need at least three if not five of every frequency standard known to man, all in perfect working order . It all depends on what you need. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Loïc MOREAU Sent: Monday, August 09, 2010 8:16 AM To: time-nuts@febo.com Subject: [time-nuts] My old new 53132A just arrived Hi all, My first goal is to verify the frequency of my different RF sources : 4420B, some DDS, a N2PK VNA and ISOTEMP 134-10, the next step with the help of an Excel spread sheet to have some idea about their respective stability. Equipped with option 010, I would like to know how in which direction to go to calibrate my unit. The frequency of the internal time base is supposed to be stable but I have no way to know the exact frequency as the unit is an old one. So I suppose I have to calibrate the gear with an external source, for now I can suppose that my 53132A is accurate to 10-6 or +-1Hz, as it is so easy to turn the front panel adjusting screw, I am not sure about the actual precision. I can take two possible direction to improve my system with an external time base. 1. acquire a rubidium 10Mhz, put in in a box with a 24V power supply Or 2. acquire a 10Mhz GMS time unit or homebrew one with one of the numerous project that we can find. Can somebody give an advice : I have no clue to choose between the solutions, apart the power drain of the first one. Regards Loïc http://www.eai.fr ___ 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] My old new 53132A just arrived
Bonsoir Loïc, and congratulations for your new, nice device. You should order the T.Bolt from fluke.l on e...y, standard easy kit with power supply and antenna, just working fine, The LCD monitor is also quite handy. You may also order an LPRO 101 Rb standard from him, so you have always a very stable reference for a low price. Alternatively, you may get a receiver for the German DCF77 signal (I can see the transmitter every day from my work place), but its a real pain for such high precision TICs. I've got the predecessor of the 53132A, i.e. the 5335A - uses a similar time interpolation circuitry with 1ns LSD / 2ns resolution (jitter), giving 9 digits/sec. If you examine your TIC/counter, could you please verify the '132A counter specs, saying 12digits /sec, although LSD is 150ps, RMS resolution 300ps, which should give 10 digits/sec only. (My 5370B resolves 11digits/sec , but has 20ps LSD and 35ps RMS resolution.) I think the agilent people are cheating a little bit (compared to former HP). Anyhow, that's just for interest. Just have fun. Frank ___ 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] My old new 53132A just arrived
On 08/09/2010 11:54 PM, Dr. Frank Stellmach wrote: Bonsoir Loïc, and congratulations for your new, nice device. You should order the T.Bolt from fluke.l on e...y, standard easy kit with power supply and antenna, just working fine, The LCD monitor is also quite handy. You may also order an LPRO 101 Rb standard from him, so you have always a very stable reference for a low price. Alternatively, you may get a receiver for the German DCF77 signal (I can see the transmitter every day from my work place), but its a real pain for such high precision TICs. I've got the predecessor of the 53132A, i.e. the 5335A - uses a similar time interpolation circuitry with 1ns LSD / 2ns resolution (jitter), giving 9 digits/sec. If you examine your TIC/counter, could you please verify the '132A counter specs, saying 12digits /sec, although LSD is 150ps, RMS resolution 300ps, which should give 10 digits/sec only. (My 5370B resolves 11digits/sec , but has 20ps LSD and 35ps RMS resolution.) I think the agilent people are cheating a little bit (compared to former HP). Uhm... well, sort off... For the older counters, the performance mapping is fairly straight-forward, but for the 53131A/53132A they follow the track laid down by J.J. Snyder in his 1980/1981 articles showing how averaging several measurements affects noise and this can be used to significantly improve the frequency/period readings, but it useless for TI readings for Allan dev style of measurements. So, comparing measurements like you just did id not a representative means of comparision. The hardware noise and resolution is aided by a software algorithm. It's not cheating for their intended use, but it can fool you if you don't know what you are looking at. This has been discussed extensively in history several times, mostly in relationship to Allan deviation measurements, where the approach gives incorrect values due to the pre-filtering it does. 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.
