Re: [time-nuts] Recommendations for a newbie?
Said wrote: you make and post negative assumptions about a seller without any first hand experience * * * It is unfair to post that kind of negative opinion without you having any first hand experience with them. This is already way out of hand -- so with this, I'm done: I think you are over-reading my comments, intent on finding offense where none was given. Please recognize that in the process, you are making and posting unfounded negative assumptions about me, the assumptions you assume that I have made, and my postings -- precisely what you accuse me of. I reiterate that I said (and certainly, I meant) nothing negative about the seller, and made no negative assumptions and no negative comments. In fact, I do have experience with him and have no complaints. My point was not that one might not get what was described; rather, it was that I cannot tell from the 58503A listings exactly what is being described, or how what is described in one listing differs from what is described in other listings that vary considerably in price. Nothing more. The End, Charles ___ 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] Recommendations for a newbie?
Hi Bob, On 09/09/2012 03:55 AM, Bob Camp wrote: Hi It would be nice if somebody came up with a fast port adaptation to one of the standard data collection programs. It would not be all that hard to do an adaptation board which creates a live USB stream for instance. Either using an FPGA or by using a handful of TTL and a Cypress USB chip. What you get is the unprocessed hardware time-stamps, but if you add a driver that does the processing (and the HP5372A Programming manual is really getting you into the gory details of bits and post-processing!) then having Timelab do it should not be too hard. It's on my list of neat things to do, but I have so many other things to do. If someone tries to do it, let me know. BTW, I happen to enable the Fast Port on my HP5372A. :) 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] Recommendations for a newbie?
Charles, maybe I did read your email wrong, I apologize for that. To me it came across as negative toward the seller and the listings, and it seems this is not how it was meant, my appologies. Bye, Said In a message dated 9/8/2012 23:05:30 Pacific Daylight Time, charles_steinm...@lavabit.com writes: I reiterate that I said (and certainly, I meant) nothing negative about the seller, and made no negative assumptions and no negative comments. In fact, I do have experience with him and have no complaints. My point was not that one might not get what was described; rather, it was that I cannot tell from the 58503A listings exactly what is being described, or how what is described in one listing differs from what is described in other listings that vary considerably in price. Nothing more. The End, Charles ___ 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] Recommendations for a newbie?
Can't compare the Z3805A to the HP58503A but I have found in the archives that the Z3805A has a 16 channel GPS receiver and it is better to find the Symmetricom labeled one as it has a real double-oven OCXO. According to a 2010 time-nut message the Z3805A is almost the same as the TBolt. On Sat, Sep 8, 2012 at 3:53 AM, Edgardo Molina xe1...@amsat.org wrote: Dear Said, Thank you for your kind explanation. I will be considering such a purchase in the near future. I will keep you informed about my experiences. You have a nice evening. Regards, Edgardo Molina Dirección IPTEL www.iptel.net.mx T : 55 55 55202444 M : 04455 20501854 Piensa en Bits SA de CV Información anexa: CONFIDENCIALIDAD DE INFORMACION Este mensaje tiene carácter confidencial. Si usted no es el destinarario de este mensaje, le suplicamos se lo notifique al remitente mediante un correo electrónico y que borre el presente mensaje y sus anexos de su computadora sin retener una copia de los mismos. Queda estrictamente prohibido copiar este mensaje o hacer usode el para cualquier propósito o divulgar su en forma parcial o total su contenido. Gracias. NON-DISCLOSURE OF INFORMATION This email is strictly confidential and may also be privileged. If you are not the intended recipient please immediately advise the sender by replying to this e-mail and then deleting the message and its attachments from your computer without keeping a copy. It is strictly forbidden to copy it or use it for any purpose or disclose its contents to any third party. Thank you. On Sep 7, 2012, at 8:14 PM, saidj...@aol.com wrote: Hi Edgardo, they work well for me, look brand-new, and came with power supply, rs-232 cable, and antenna. I think it's a 5V antenna. The unit had about 37000 on the lifetime. The seller has close up photos, that's what the units look like. I plugged in the power, ran GPSCon to start an Auto-Survey, and they just worked. I now get less than 3us predicted drift over 24 hours from one of the units, which is quite good according to others. I think these are pretty good for the money (free shipping on mine) but there are differences between the three units I have just like the Z3801A plots on leapsecond.com. Hope that helps, Said In a message dated 9/7/2012 17:13:22 Pacific Daylight Time, xe1...@amsat.org writes: Dear Said, Good afternoon. How is the service and cosmetic condition of the HP GPS products you have bought from this source? I am considering a Z3805A just for the sake of owning one and the versatility of plug and play. Still afraid to take the plunge. Did you buy a raw unit? Or as a kit with antenna. Is that a 5V or 12V antenna? I am integrating a TBolt into a 1U rack case which also has space for a Rb oscillator for future disciplining. Got a nice TBolt monitor and would love to also include a frequency divider to get 5 and 1MHz from the TBolt. Your kind comments are welcome. Thank you. Regards, Edgardo Molina Dirección IPTEL ___ 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] Recommendations for a newbie?
Hi Ok, I've got at least one of all of these sitting in the basement. They are a very much mixed bag. Some of the HP's are quite good. Others not so much. The variation isn't so much model to model. They vary unit to unit. The TBolt's vary by year. Roughly they group as pre-2001, 2001 to 2003, and post 2004. The HP's also seem to die a bit quicker than the TBolts. I'd *guess* the failure rate is at least 3X. On a good unit, the HP Smart Clock software does a better job than the TBolt stock software. On a unit with issues the software chugs (switches settings) a lot. A manually tuned TBolt in a good environment can do very well. In a poor environment it's going go look like a boosted single oven 3801, but not be as good as the true double oven (MTI OCXO) version of the 3805. The strange temperature chip in the later TBolts isn't much of an issue. The chip is poorly located for temperature control. It only seems to impact the plots on Lady Heather. Trimble wasn't bothered enough by it to patch the firmware. Bottom line, If the price is identical for all of them, go with the HP's. If the TBolt's are half (or 1/4) the delivered price of the HP's go with the TBolt. Either way, plan on getting a couple of them. Bob On Sep 8, 2012, at 8:11 AM, Azelio Boriani azelio.bori...@screen.it wrote: Can't compare the Z3805A to the HP58503A but I have found in the archives that the Z3805A has a 16 channel GPS receiver and it is better to find the Symmetricom labeled one as it has a real double-oven OCXO. According to a 2010 time-nut message the Z3805A is almost the same as the TBolt. On Sat, Sep 8, 2012 at 3:53 AM, Edgardo Molina xe1...@amsat.org wrote: Dear Said, Thank you for your kind explanation. I will be considering such a purchase in the near future. I will keep you informed about my experiences. You have a nice evening. Regards, Edgardo Molina Dirección IPTEL www.iptel.net.mx T : 55 55 55202444 M : 04455 20501854 Piensa en Bits SA de CV Información anexa: CONFIDENCIALIDAD DE INFORMACION Este mensaje tiene carácter confidencial. Si usted no es el destinarario de este mensaje, le suplicamos se lo notifique al remitente mediante un correo electrónico y que borre el presente mensaje y sus anexos de su computadora sin retener una copia de los mismos. Queda estrictamente prohibido copiar este mensaje o hacer usode el para cualquier propósito o divulgar su en forma parcial o total su contenido. Gracias. NON-DISCLOSURE OF INFORMATION This email is strictly confidential and may also be privileged. If you are not the intended recipient please immediately advise the sender by replying to this e-mail and then deleting the message and its attachments from your computer without keeping a copy. It is strictly forbidden to copy it or use it for any purpose or disclose its contents to any third party. Thank you. On Sep 7, 2012, at 8:14 PM, saidj...@aol.com wrote: Hi Edgardo, they work well for me, look brand-new, and came with power supply, rs-232 cable, and antenna. I think it's a 5V antenna. The unit had about 37000 on the lifetime. The seller has close up photos, that's what the units look like. I plugged in the power, ran GPSCon to start an Auto-Survey, and they just worked. I now get less than 3us predicted drift over 24 hours from one of the units, which is quite good according to others. I think these are pretty good for the money (free shipping on mine) but there are differences between the three units I have just like the Z3801A plots on leapsecond.com. Hope that helps, Said In a message dated 9/7/2012 17:13:22 Pacific Daylight Time, xe1...@amsat.org writes: Dear Said, Good afternoon. How is the service and cosmetic condition of the HP GPS products you have bought from this source? I am considering a Z3805A just for the sake of owning one and the versatility of plug and play. Still afraid to take the plunge. Did you buy a raw unit? Or as a kit with antenna. Is that a 5V or 12V antenna? I am integrating a TBolt into a 1U rack case which also has space for a Rb oscillator for future disciplining. Got a nice TBolt monitor and would love to also include a frequency divider to get 5 and 1MHz from the TBolt. Your kind comments are welcome. Thank you. Regards, Edgardo Molina Dirección IPTEL ___ 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
Re: [time-nuts] Recommendations for a newbie?
Not being a time nut but a frequency nut I lack some of the time test equipment, but my partner on our joint development work makes up for it. So he among other things recently looked at the 1 pps output of the Tbolt against a Cesium. Using a HP 5352A with 500 samples over 50% are within +- 300 psec and all within +-1 nsec. It makes an excellent GPS receiver and the 10 MHz out make a good reference for counters, spectrum analyser and Signal Generators. Good place to start, specially because of all the software available. Any significant improvement on it should be well thought out and lower A/V products are hard to find and seldom cheap. Bert Kehren On Fri, Sep 7, 2012 at 11:34 AM, Robert Liesenfeld xu...@xunil.net wrote: Hello- My name is Robert Liesenfeld, I discovered this mailing list via the fascinating website leapsecond.com. I'm an amateur radio operator (AK6L) and builder, and my interest in precise timekeeping initially stemmed from simply wanting a very accurate clock source to which I could reference my test equipment (counter, spectrum analyzer, etc), but has expanded to a desire to perform timekeeping experiments. I have several questions; I looked for a FAQ but couldn't find one, so I hope it's alright to ask here. I'm considering the purchase of a GPS receiver to serve as my workbench 10MHz source. Since learning about precise timekeeping, I've also become interested in some experiments, such as measuring the stability of the mains, the effect of the ionosphere on WWV/WWVH signals, and so on. So far I've looked at various HP Z-boxes (Z3816, Z3815, Z3801, Z3805) and the Trimble Thunderbolt receiver. All of these seem to be in the $200-$500 range I'm targeting, but it's not clear what the differences are. I've read the Thunderbolt is an older design with fewer channels, but I don't know if that's really a problem for my intended use. I've also seen many rubidium devices on eBay, most seem to have been removed from CDMA cell tower service. Does anyone here have any experience with such devices, are the ex-cell-tower units any good? I have read that a rubidium standard's short-term stability is not as good as a GPSDO, and that they're mainly used for holdover - is my understanding correct? My thought is to (eventually) use a rubidium device to stabilize a GPSDO should the receiver lose satellite signal. Thank you in advance for any advice! -Robert ___ 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] Recommendations for a newbie?
Hi If you stretch out to 10,000 samples and watch over a full 24 hour period, you likely will see some in the +/-1.5 ns region. Bob On Sep 8, 2012, at 11:06 AM, ewkeh...@aol.com wrote: Not being a time nut but a frequency nut I lack some of the time test equipment, but my partner on our joint development work makes up for it. So he among other things recently looked at the 1 pps output of the Tbolt against a Cesium. Using a HP 5352A with 500 samples over 50% are within +- 300 psec and all within +-1 nsec. It makes an excellent GPS receiver and the 10 MHz out make a good reference for counters, spectrum analyser and Signal Generators. Good place to start, specially because of all the software available. Any significant improvement on it should be well thought out and lower A/V products are hard to find and seldom cheap. Bert Kehren On Fri, Sep 7, 2012 at 11:34 AM, Robert Liesenfeld xu...@xunil.net wrote: Hello- My name is Robert Liesenfeld, I discovered this mailing list via the fascinating website leapsecond.com. I'm an amateur radio operator (AK6L) and builder, and my interest in precise timekeeping initially stemmed from simply wanting a very accurate clock source to which I could reference my test equipment (counter, spectrum analyzer, etc), but has expanded to a desire to perform timekeeping experiments. I have several questions; I looked for a FAQ but couldn't find one, so I hope it's alright to ask here. I'm considering the purchase of a GPS receiver to serve as my workbench 10MHz source. Since learning about precise timekeeping, I've also become interested in some experiments, such as measuring the stability of the mains, the effect of the ionosphere on WWV/WWVH signals, and so on. So far I've looked at various HP Z-boxes (Z3816, Z3815, Z3801, Z3805) and the Trimble Thunderbolt receiver. All of these seem to be in the $200-$500 range I'm targeting, but it's not clear what the differences are. I've read the Thunderbolt is an older design with fewer channels, but I don't know if that's really a problem for my intended use. I've also seen many rubidium devices on eBay, most seem to have been removed from CDMA cell tower service. Does anyone here have any experience with such devices, are the ex-cell-tower units any good? I have read that a rubidium standard's short-term stability is not as good as a GPSDO, and that they're mainly used for holdover - is my understanding correct? My thought is to (eventually) use a rubidium device to stabilize a GPSDO should the receiver lose satellite signal. Thank you in advance for any advice! -Robert ___ 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. ___ 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] Recommendations for a newbie?
For a GPS receiver that is in my book acceptable but then I am not a time-nut. I use that signal to discipline Rb's. Works for me. Bert Kehren In a message dated 9/8/2012 12:47:52 P.M. Eastern Daylight Time, li...@rtty.us writes: Hi If you stretch out to 10,000 samples and watch over a full 24 hour period, you likely will see some in the +/-1.5 ns region. Bob On Sep 8, 2012, at 11:06 AM, ewkeh...@aol.com wrote: Not being a time nut but a frequency nut I lack some of the time test equipment, but my partner on our joint development work makes up for it. So he among other things recently looked at the 1 pps output of the Tbolt against a Cesium. Using a HP 5352A with 500 samples over 50% are within +- 300 psec and all within +-1 nsec. It makes an excellent GPS receiver and the 10 MHz out make a good reference for counters, spectrum analyser and Signal Generators. Good place to start, specially because of all the software available. Any significant improvement on it should be well thought out and lower A/V products are hard to find and seldom cheap. Bert Kehren On Fri, Sep 7, 2012 at 11:34 AM, Robert Liesenfeld xu...@xunil.net wrote: Hello- My name is Robert Liesenfeld, I discovered this mailing list via the fascinating website leapsecond.com. I'm an amateur radio operator (AK6L) and builder, and my interest in precise timekeeping initially stemmed from simply wanting a very accurate clock source to which I could reference my test equipment (counter, spectrum analyzer, etc), but has expanded to a desire to perform timekeeping experiments. I have several questions; I looked for a FAQ but couldn't find one, so I hope it's alright to ask here. I'm considering the purchase of a GPS receiver to serve as my workbench 10MHz source. Since learning about precise timekeeping, I've also become interested in some experiments, such as measuring the stability of the mains, the effect of the ionosphere on WWV/WWVH signals, and so on. So far I've looked at various HP Z-boxes (Z3816, Z3815, Z3801, Z3805) and the Trimble Thunderbolt receiver. All of these seem to be in the $200-$500 range I'm targeting, but it's not clear what the differences are. I've read the Thunderbolt is an older design with fewer channels, but I don't know if that's really a problem for my intended use. I've also seen many rubidium devices on eBay, most seem to have been removed from CDMA cell tower service. Does anyone here have any experience with such devices, are the ex-cell-tower units any good? I have read that a rubidium standard's short-term stability is not as good as a GPSDO, and that they're mainly used for holdover - is my understanding correct? My thought is to (eventually) use a rubidium device to stabilize a GPSDO should the receiver lose satellite signal. Thank you in advance for any advice! -Robert ___ 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. ___ 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] Recommendations for a newbie?
Said wrote (re: eBay 58503As): they work well for me, look brand-new, and came with power supply, rs-232 cable, and antenna. I think it's a 5V antenna. The unit had about 37000 on the lifetime. The seller has close up photos, that's what the units look like. I plugged in the power, ran GPSCon to start an Auto-Survey, and they just worked. Looking at the current and completed eBay listings for the 58503As from Hong Kong, I notice that the seller seems to have conversion units based on the Z3801 and on the Z3805, and some that may be factory 58503As. The listing text for all of them says they have 6-channel receivers. Some have no PPS outputs, some have one, and some have two. Some have internal AC power supplies, some have external supplies. There appear to be at least two different rear-panel layouts. They are priced from $260 to $999, and it does not seem obvious what justifies the radically different prices (aside from different antennas). Based on these confusing listings, I'd be very reluctant to count on finding anything specific inside the housing (e.g, a particular OCXO) if I bought one, except possibly the $999 units that may be factory 58503As. Best regards, Charles ___ 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] Recommendations for a newbie?
Wow, thank you everyone for the wealth of information and advice. It sounds like for my needs, either the TBolt or HP Z-box will do just fine, and cost is going to be more of a driver than anything else. It seems that the HPs are more plentiful on a certain well-known auction site, but Thunderbolts are cheaper. I'll keep an eye out for good deals. Again, big thanks to everyone for the information, and for the welcoming atmosphere! -Rob On Sat, Sep 8, 2012 at 10:32 AM, Charles P. Steinmetz charles_steinm...@lavabit.com wrote: Said wrote (re: eBay 58503As): they work well for me, look brand-new, and came with power supply, rs-232 cable, and antenna. I think it's a 5V antenna. The unit had about 37000 on the lifetime. The seller has close up photos, that's what the units look like. I plugged in the power, ran GPSCon to start an Auto-Survey, and they just worked. Looking at the current and completed eBay listings for the 58503As from Hong Kong, I notice that the seller seems to have conversion units based on the Z3801 and on the Z3805, and some that may be factory 58503As. The listing text for all of them says they have 6-channel receivers. Some have no PPS outputs, some have one, and some have two. Some have internal AC power supplies, some have external supplies. There appear to be at least two different rear-panel layouts. They are priced from $260 to $999, and it does not seem obvious what justifies the radically different prices (aside from different antennas). Based on these confusing listings, I'd be very reluctant to count on finding anything specific inside the housing (e.g, a particular OCXO) if I bought one, except possibly the $999 units that may be factory 58503As. Best regards, Charles __**_ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/** mailman/listinfo/time-nutshttps://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] Recommendations for a newbie?
The HP5352A has a 2nS single shot resolution: how can you have 300pS or 1nS measures? On Sat, Sep 8, 2012 at 9:08 PM, Robert Liesenfeld xu...@xunil.net wrote: Wow, thank you everyone for the wealth of information and advice. It sounds like for my needs, either the TBolt or HP Z-box will do just fine, and cost is going to be more of a driver than anything else. It seems that the HPs are more plentiful on a certain well-known auction site, but Thunderbolts are cheaper. I'll keep an eye out for good deals. Again, big thanks to everyone for the information, and for the welcoming atmosphere! -Rob On Sat, Sep 8, 2012 at 10:32 AM, Charles P. Steinmetz charles_steinm...@lavabit.com wrote: Said wrote (re: eBay 58503As): they work well for me, look brand-new, and came with power supply, rs-232 cable, and antenna. I think it's a 5V antenna. The unit had about 37000 on the lifetime. The seller has close up photos, that's what the units look like. I plugged in the power, ran GPSCon to start an Auto-Survey, and they just worked. Looking at the current and completed eBay listings for the 58503As from Hong Kong, I notice that the seller seems to have conversion units based on the Z3801 and on the Z3805, and some that may be factory 58503As. The listing text for all of them says they have 6-channel receivers. Some have no PPS outputs, some have one, and some have two. Some have internal AC power supplies, some have external supplies. There appear to be at least two different rear-panel layouts. They are priced from $260 to $999, and it does not seem obvious what justifies the radically different prices (aside from different antennas). Based on these confusing listings, I'd be very reluctant to count on finding anything specific inside the housing (e.g, a particular OCXO) if I bought one, except possibly the $999 units that may be factory 58503As. Best regards, Charles __**_ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/** mailman/listinfo/time-nuts 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] Recommendations for a newbie?
Charles, Not sure why this is confusing to you, he clearly explains all the differences in the description, and what is shown in the photos is exactly what I received. The z3805A based units cost more than Z3801As, and the ones with one or two 1pps and 10Mhz outputs cost slightly more. He upgraded all of them to 58503A firmware and put rubber grommets on the outside, and the units I got have 10811As in them just as shown in the photos. And he has fantastic feedback. The two recent units I got have 5 dB better phase noise than the Thunderbolts I have seen, especially close-in, and about 3x better ADEV. They come with Satstat. Not to mention great packaging and ultra fast shipping, and no shipping charge. If one can afford them, they will outperform a Thunderbolt by far. Also these are units using leaded solder, the Thunderbolt is RoHs, so they will eventually die from tin-whiskering.. And they can be easily run from a battery. What more can one ask for $550? Bye, Said On Sep 8, 2012, at 10:32, Charles P. Steinmetz charles_steinm...@lavabit.com wrote: Said wrote (re: eBay 58503As): they work well for me, look brand-new, and came with power supply, rs-232 cable, and antenna. I think it's a 5V antenna. The unit had about 37000 on the lifetime. The seller has close up photos, that's what the units look like. I plugged in the power, ran GPSCon to start an Auto-Survey, and they just worked. Looking at the current and completed eBay listings for the 58503As from Hong Kong, I notice that the seller seems to have conversion units based on the Z3801 and on the Z3805, and some that may be factory 58503As. The listing text for all of them says they have 6-channel receivers. Some have no PPS outputs, some have one, and some have two. Some have internal AC power supplies, some have external supplies. There appear to be at least two different rear-panel layouts. They are priced from $260 to $999, and it does not seem obvious what justifies the radically different prices (aside from different antennas). Based on these confusing listings, I'd be very reluctant to count on finding anything specific inside the housing (e.g, a particular OCXO) if I bought one, except possibly the $999 units that may be factory 58503As. Best regards, Charles ___ 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] Recommendations for a newbie?
Sorry my mistake 5372A I will send you the data direct Bert Kehren In a message dated 9/8/2012 6:15:59 P.M. Eastern Daylight Time, azelio.bori...@screen.it writes: The HP5352A has a 2nS single shot resolution: how can you have 300pS or 1nS measures? On Sat, Sep 8, 2012 at 9:08 PM, Robert Liesenfeld xu...@xunil.net wrote: Wow, thank you everyone for the wealth of information and advice. It sounds like for my needs, either the TBolt or HP Z-box will do just fine, and cost is going to be more of a driver than anything else. It seems that the HPs are more plentiful on a certain well-known auction site, but Thunderbolts are cheaper. I'll keep an eye out for good deals. Again, big thanks to everyone for the information, and for the welcoming atmosphere! -Rob On Sat, Sep 8, 2012 at 10:32 AM, Charles P. Steinmetz charles_steinm...@lavabit.com wrote: Said wrote (re: eBay 58503As): they work well for me, look brand-new, and came with power supply, rs-232 cable, and antenna. I think it's a 5V antenna. The unit had about 37000 on the lifetime. The seller has close up photos, that's what the units look like. I plugged in the power, ran GPSCon to start an Auto-Survey, and they just worked. Looking at the current and completed eBay listings for the 58503As from Hong Kong, I notice that the seller seems to have conversion units based on the Z3801 and on the Z3805, and some that may be factory 58503As. The listing text for all of them says they have 6-channel receivers. Some have no PPS outputs, some have one, and some have two. Some have internal AC power supplies, some have external supplies. There appear to be at least two different rear-panel layouts. They are priced from $260 to $999, and it does not seem obvious what justifies the radically different prices (aside from different antennas). Based on these confusing listings, I'd be very reluctant to count on finding anything specific inside the housing (e.g, a particular OCXO) if I bought one, except possibly the $999 units that may be factory 58503As. Best regards, Charles __**_ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/** mailman/listinfo/time-nuts 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. ___ 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] Recommendations for a newbie?
Hi You will have a tough time with the 5372 running the longer time spans… Bob On Sep 8, 2012, at 9:08 PM, ewkeh...@aol.com wrote: Sorry my mistake 5372A I will send you the data direct Bert Kehren In a message dated 9/8/2012 6:15:59 P.M. Eastern Daylight Time, azelio.bori...@screen.it writes: The HP5352A has a 2nS single shot resolution: how can you have 300pS or 1nS measures? On Sat, Sep 8, 2012 at 9:08 PM, Robert Liesenfeld xu...@xunil.net wrote: Wow, thank you everyone for the wealth of information and advice. It sounds like for my needs, either the TBolt or HP Z-box will do just fine, and cost is going to be more of a driver than anything else. It seems that the HPs are more plentiful on a certain well-known auction site, but Thunderbolts are cheaper. I'll keep an eye out for good deals. Again, big thanks to everyone for the information, and for the welcoming atmosphere! -Rob On Sat, Sep 8, 2012 at 10:32 AM, Charles P. Steinmetz charles_steinm...@lavabit.com wrote: Said wrote (re: eBay 58503As): they work well for me, look brand-new, and came with power supply, rs-232 cable, and antenna. I think it's a 5V antenna. The unit had about 37000 on the lifetime. The seller has close up photos, that's what the units look like. I plugged in the power, ran GPSCon to start an Auto-Survey, and they just worked. Looking at the current and completed eBay listings for the 58503As from Hong Kong, I notice that the seller seems to have conversion units based on the Z3801 and on the Z3805, and some that may be factory 58503As. The listing text for all of them says they have 6-channel receivers. Some have no PPS outputs, some have one, and some have two. Some have internal AC power supplies, some have external supplies. There appear to be at least two different rear-panel layouts. They are priced from $260 to $999, and it does not seem obvious what justifies the radically different prices (aside from different antennas). Based on these confusing listings, I'd be very reluctant to count on finding anything specific inside the housing (e.g, a particular OCXO) if I bought one, except possibly the $999 units that may be factory 58503As. Best regards, Charles __**_ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/** mailman/listinfo/time-nuts 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. ___ 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] Recommendations for a newbie?
On 09/09/2012 03:34 AM, Bob Camp wrote: Hi You will have a tough time with the 5372 running the longer time spans… Yes and no. Using the 5372A internal memory, you have 8192 memory positions to play with. You can mitigate that by parametrisation, Fast Port or just use it as a triggered single-shot counter. 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] Recommendations for a newbie?
Hi It would be nice if somebody came up with a fast port adaptation to one of the standard data collection programs. Bob On Sep 8, 2012, at 9:45 PM, Magnus Danielson mag...@rubidium.dyndns.org wrote: On 09/09/2012 03:34 AM, Bob Camp wrote: Hi You will have a tough time with the 5372 running the longer time spans… Yes and no. Using the 5372A internal memory, you have 8192 memory positions to play with. You can mitigate that by parametrisation, Fast Port or just use it as a triggered single-shot counter. 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. ___ 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] Recommendations for a newbie?
Said wrote: Not sure why this is confusing to you, he clearly explains all the differences in the description I don't see anyplace where he explains all the differences, clearly or otherwise. And as I said, ALL of the descriptions I've seen (including the descriptions of the Z3805-based conversions and what may be original 58503As) say the unit tracks 6 satellites. Why so defensive? I cast no aspersions on you or on the seller. I just said that the descriptions I've seen do not appear to me to explain the great price differences and that there appear to be many different variants, so getting exactly what someone else got may not be easy or straightforward. Prospective buyers can judge for themselves. Best regards, Charles ___ 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] Recommendations for a newbie?
Charles, Because you make and post negative assumptions about a seller without any first hand experience based on your opinion on what you consider a sub-par EBay listing by a non-English seller. I'd be very reluctant to count on finding anything specific inside the housing This is close to calling the seller a fraud in my opinion. This seller gave me a most positive EBay purchase, with a unit that basically looked factory new and one could tell they spent a lot of time putting this package together. It is unfair to post that kind of negative opinion without you having any first hand experience with them. I wish most stateside sellers would be half as good as this seller, and consider him an asset to folks like us. I remember what it was like before we had EBay and could buy from these kind of sources, and hope we never have to go back to those dark days. Bye, Said Sent From iPhone On Sep 8, 2012, at 20:16, Charles P. Steinmetz charles_steinm...@lavabit.com wrote: Said wrote: Not sure why this is confusing to you, he clearly explains all the differences in the description I don't see anyplace where he explains all the differences, clearly or otherwise. And as I said, ALL of the descriptions I've seen (including the descriptions of the Z3805-based conversions and what may be original 58503As) say the unit tracks 6 satellites. Why so defensive? I cast no aspersions on you or on the seller. I just said that the descriptions I've seen do not appear to me to explain the great price differences and that there appear to be many different variants, so getting exactly what someone else got may not be easy or straightforward. Prospective buyers can judge for themselves. Best regards, Charles ___ 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] Recommendations for a newbie?
You want to start with a GPSDO. I like the Trimble Thunderbolt. The price is right and they're readily available. I have no experience with the HP units but they seem to be highly regarded. Rb oscillators are great for some things, but need to be calibrated. That's where the GPSDO comes in. Also, don't forget the antenna. You'll want something along these lines: http://www.ebay.com/itm/lucent-GPS-Timing-Reference-Antenna-antenne-40db-N-/230848464732?pt=GPS_Antennashash=item35bfa4075c#ht_2199wt_1404 Welcome aboard, and I'm apologizing in advance for how much money you'll be spending on new toys. -Bob On Fri, Sep 7, 2012 at 11:34 AM, Robert Liesenfeld xu...@xunil.net wrote: Hello- My name is Robert Liesenfeld, I discovered this mailing list via the fascinating website leapsecond.com. I'm an amateur radio operator (AK6L) and builder, and my interest in precise timekeeping initially stemmed from simply wanting a very accurate clock source to which I could reference my test equipment (counter, spectrum analyzer, etc), but has expanded to a desire to perform timekeeping experiments. I have several questions; I looked for a FAQ but couldn't find one, so I hope it's alright to ask here. I'm considering the purchase of a GPS receiver to serve as my workbench 10MHz source. Since learning about precise timekeeping, I've also become interested in some experiments, such as measuring the stability of the mains, the effect of the ionosphere on WWV/WWVH signals, and so on. So far I've looked at various HP Z-boxes (Z3816, Z3815, Z3801, Z3805) and the Trimble Thunderbolt receiver. All of these seem to be in the $200-$500 range I'm targeting, but it's not clear what the differences are. I've read the Thunderbolt is an older design with fewer channels, but I don't know if that's really a problem for my intended use. I've also seen many rubidium devices on eBay, most seem to have been removed from CDMA cell tower service. Does anyone here have any experience with such devices, are the ex-cell-tower units any good? I have read that a rubidium standard's short-term stability is not as good as a GPSDO, and that they're mainly used for holdover - is my understanding correct? My thought is to (eventually) use a rubidium device to stabilize a GPSDO should the receiver lose satellite signal. Thank you in advance for any advice! -Robert ___ 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] Recommendations for a newbie?
Welcome aboard, yes, there is no FAQ about how to start in this hobby... should I try to implement one? Anyway, start with a Trimble Thunderbolt (aka TBolt), later you will know why it is highly recommended (direct OCXO disciplining and LH software support, mainly). I have a Z3815A with the famous (or infamous) E1938A hockey puck OCXO. They are all GPSDOs and there should not be any difference among them but, yes, there are differences in their performance and being a time-nut means test and find out. Then there are GPS disciplined Rubidiums, but take this step after the first GPSDO is correctly installed and stabilized. Start with the antenna: find a suitable place, with a 360 deg clear view of the sky, a satellite TV cable (sounds unusual, but works great). On Fri, Sep 7, 2012 at 8:52 PM, Robert Darlington rdarling...@gmail.comwrote: You want to start with a GPSDO. I like the Trimble Thunderbolt. The price is right and they're readily available. I have no experience with the HP units but they seem to be highly regarded. Rb oscillators are great for some things, but need to be calibrated. That's where the GPSDO comes in. Also, don't forget the antenna. You'll want something along these lines: http://www.ebay.com/itm/lucent-GPS-Timing-Reference-Antenna-antenne-40db-N-/230848464732?pt=GPS_Antennashash=item35bfa4075c#ht_2199wt_1404 Welcome aboard, and I'm apologizing in advance for how much money you'll be spending on new toys. -Bob On Fri, Sep 7, 2012 at 11:34 AM, Robert Liesenfeld xu...@xunil.net wrote: Hello- My name is Robert Liesenfeld, I discovered this mailing list via the fascinating website leapsecond.com. I'm an amateur radio operator (AK6L) and builder, and my interest in precise timekeeping initially stemmed from simply wanting a very accurate clock source to which I could reference my test equipment (counter, spectrum analyzer, etc), but has expanded to a desire to perform timekeeping experiments. I have several questions; I looked for a FAQ but couldn't find one, so I hope it's alright to ask here. I'm considering the purchase of a GPS receiver to serve as my workbench 10MHz source. Since learning about precise timekeeping, I've also become interested in some experiments, such as measuring the stability of the mains, the effect of the ionosphere on WWV/WWVH signals, and so on. So far I've looked at various HP Z-boxes (Z3816, Z3815, Z3801, Z3805) and the Trimble Thunderbolt receiver. All of these seem to be in the $200-$500 range I'm targeting, but it's not clear what the differences are. I've read the Thunderbolt is an older design with fewer channels, but I don't know if that's really a problem for my intended use. I've also seen many rubidium devices on eBay, most seem to have been removed from CDMA cell tower service. Does anyone here have any experience with such devices, are the ex-cell-tower units any good? I have read that a rubidium standard's short-term stability is not as good as a GPSDO, and that they're mainly used for holdover - is my understanding correct? My thought is to (eventually) use a rubidium device to stabilize a GPSDO should the receiver lose satellite signal. Thank you in advance for any advice! -Robert ___ 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] Recommendations for a newbie?
Hello Robert, your question is like asking which car you should buy, or which airline you should fly :) Everyone will have a different answer. But I do not recommend the Thunderbolts, it's a crab-shoot with them (different versions have different performance, the new ones are actually worse than older versions because of the temperature chip issue, the GPS is known to have lock issues, they don't work well until you spend a lot of time fine-tuning the parameters, etc etc) - that has all been discussed here ad-infinitum and you can find it in the archives. I recommend you search Ebay for HP 58503A. I just bought a number of them from a very well known seller in China, and they are absolutely superb, much better than any Rubidium unit I have tested. Much better than the Thunderbolt I have, and just slightly more expensive. He sells an entire kit for around $500, and it arrived here in less than a week (Northern California). This seller starts those units at around $260 I think. Performance you can get from these if you get a good one is: phase noise floor of around -163dBc, ADEV of 7E-013 to about 1E-012 to over 100s. Leapsecond.com has a number of test papers on these units. Caveat-emptor: there are significant unit-to-unit variations as with all GPSDO, Tom on leapsecond.com discusses this in detail. BTW: these are essentially the same unit as the Z3801A, just different software (ID string). I also have a Z3815A, and it is not even in the same class as the Z3801A/58503A. It is very noisy compared to the 58503A unit. I do not recommend the Z3815A, but it is a unique oscillator design,and some folks collect it for that oscillator. The 58503A uses a double oven version of the HP 10811A, which is a fantastic oscillator if you get a well-working one. If you want something low-cost with reasonable performance, brand new with warranty, antenna, and accessories, Jackson Labs Technologies, Inc. has the GPSTCXO eval kit for Time-Nuts special academic pricing of $300, which we believe is the lowest-cost true GPSDO (not NCO) in current production. Disclaimer: I work for them. bye, Said In a message dated 9/7/2012 13:09:24 Pacific Daylight Time, azelio.bori...@screen.it writes: Welcome aboard, yes, there is no FAQ about how to start in this hobby... should I try to implement one? Anyway, start with a Trimble Thunderbolt (aka TBolt), later you will know why it is highly recommended (direct OCXO disciplining and LH software support, mainly). I have a Z3815A with the famous (or infamous) E1938A hockey puck OCXO. They are all GPSDOs and there should not be any difference among them but, yes, there are differences in their performance and being a time-nut means test and find out. Then there are GPS disciplined Rubidiums, but take this step after the first GPSDO is correctly installed and stabilized. Start with the antenna: find a suitable place, with a 360 deg clear view of the sky, a satellite TV cable (sounds unusual, but works great). On Fri, Sep 7, 2012 at 8:52 PM, Robert Darlington rdarling...@gmail.comwrote: You want to start with a GPSDO. I like the Trimble Thunderbolt. The price is right and they're readily available. I have no experience with the HP units but they seem to be highly regarded. Rb oscillators are great for some things, but need to be calibrated. That's where the GPSDO comes in. Also, don't forget the antenna. You'll want something along these lines: http://www.ebay.com/itm/lucent-GPS-Timing-Reference-Antenna-antenne-40db-N-/230848464732?pt=GPS_Antennashash=item35bfa4075c#ht_2199wt_1404 Welcome aboard, and I'm apologizing in advance for how much money you'll be spending on new toys. -Bob ___ 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] Recommendations for a newbie?
On Fri, Sep 7, 2012 at 10:34 AM, Robert Liesenfeld xu...@xunil.net wrote: Hello- I'm considering the purchase of a GPS receiver to serve as my workbench 10MHz source. Buy a Thunderbolt first. This is I think the best value and technicaly hard to beat. These is much support for the t-bolt here. many people know about them. ...I have read that a rubidium standard's short-term stability is not as good as a GPSDO, and that they're mainly used for holdover - is my understanding correct? My thought is to (eventually) use a rubidium device to stabilize a GPSDO should the receiver lose satellite signal. Hold over is their best use. But they work well as a portable standard and if you need something that can work quickly after power is applied with no need to set up a GPS antenna and wait for a self-survey. I is actually very unlikely that the GPS signal will fail. This might happen on a cell tower where some transmitter might fail and jam GPS but it is unlikely at your home. I think the Rb's best use is is portable or temporary uses where yo can't set up a GPS. One more thing. If your budget were lower you could build a GPSDO using a $20 GPS and a $20 OCXO plus some glue logic and get pretty good performance for about $100. The reason to build might be any of these (1) you want soething that uses very low power (2) you need some feature like automated failover to Rb on loss of signal, or (3) self education. Chris Albertson Redondo Beach, California ___ 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] Recommendations for a newbie?
Robert, my bad, that seller offers 58503A units based on both Z3801A and Z3805A. The latter has a 16 channel GPS receiver, so seems to me much more desirable than the Z3801A. $50 difference. I have been testing the latter, not the former. bye, Said In a message dated 9/7/2012 13:37:52 Pacific Daylight Time, saidj...@aol.com writes: BTW: these are essentially the same unit as the Z3801A, just different software (ID string). ___ 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] Recommendations for a newbie?
Good one, the HP58503A, actually it is my reference at work. On Fri, Sep 7, 2012 at 10:37 PM, saidj...@aol.com wrote: Hello Robert, your question is like asking which car you should buy, or which airline you should fly :) Everyone will have a different answer. But I do not recommend the Thunderbolts, it's a crab-shoot with them (different versions have different performance, the new ones are actually worse than older versions because of the temperature chip issue, the GPS is known to have lock issues, they don't work well until you spend a lot of time fine-tuning the parameters, etc etc) - that has all been discussed here ad-infinitum and you can find it in the archives. I recommend you search Ebay for HP 58503A. I just bought a number of them from a very well known seller in China, and they are absolutely superb, much better than any Rubidium unit I have tested. Much better than the Thunderbolt I have, and just slightly more expensive. He sells an entire kit for around $500, and it arrived here in less than a week (Northern California). This seller starts those units at around $260 I think. Performance you can get from these if you get a good one is: phase noise floor of around -163dBc, ADEV of 7E-013 to about 1E-012 to over 100s. Leapsecond.com has a number of test papers on these units. Caveat-emptor: there are significant unit-to-unit variations as with all GPSDO, Tom on leapsecond.comdiscusses this in detail. BTW: these are essentially the same unit as the Z3801A, just different software (ID string). I also have a Z3815A, and it is not even in the same class as the Z3801A/58503A. It is very noisy compared to the 58503A unit. I do not recommend the Z3815A, but it is a unique oscillator design,and some folks collect it for that oscillator. The 58503A uses a double oven version of the HP 10811A, which is a fantastic oscillator if you get a well-working one. If you want something low-cost with reasonable performance, brand new with warranty, antenna, and accessories, Jackson Labs Technologies, Inc. has the GPSTCXO eval kit for Time-Nuts special academic pricing of $300, which we believe is the lowest-cost true GPSDO (not NCO) in current production. Disclaimer: I work for them. bye, Said In a message dated 9/7/2012 13:09:24 Pacific Daylight Time, azelio.bori...@screen.it writes: Welcome aboard, yes, there is no FAQ about how to start in this hobby... should I try to implement one? Anyway, start with a Trimble Thunderbolt (aka TBolt), later you will know why it is highly recommended (direct OCXO disciplining and LH software support, mainly). I have a Z3815A with the famous (or infamous) E1938A hockey puck OCXO. They are all GPSDOs and there should not be any difference among them but, yes, there are differences in their performance and being a time-nut means test and find out. Then there are GPS disciplined Rubidiums, but take this step after the first GPSDO is correctly installed and stabilized. Start with the antenna: find a suitable place, with a 360 deg clear view of the sky, a satellite TV cable (sounds unusual, but works great). On Fri, Sep 7, 2012 at 8:52 PM, Robert Darlington rdarling...@gmail.comwrote: You want to start with a GPSDO. I like the Trimble Thunderbolt. The price is right and they're readily available. I have no experience with the HP units but they seem to be highly regarded. Rb oscillators are great for some things, but need to be calibrated. That's where the GPSDO comes in. Also, don't forget the antenna. You'll want something along these lines: http://www.ebay.com/itm/lucent-GPS-Timing-Reference-Antenna-antenne-40db-N-/230848464732?pt=GPS_Antennashash=item35bfa4075c#ht_2199wt_1404 Welcome aboard, and I'm apologizing in advance for how much money you'll be spending on new toys. -Bob ___ 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] Recommendations for a newbie?
Robert, you have gotten some good advice already. With regards to rubidium standards I've bought several of the cheaper rubidium units and with the benefit of hindsight I would have put the money towards a higher quality item such as a PRS 10. There are some good write ups on line that summarize the performance of the more commonly avaliable rubidium standards. If you haven't already done so you might want to start considering what type of measurement gear you are going to use for your experiments. Before purchasing a time interval counter I was able to do quite a bit of experimenting using a dual trace oscilloscope to compare two signals. Regards Mark Spencer ___ 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] Recommendations for a newbie?
Said, Where do you rank the Samsung GCRU-D among these? Jerry -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of saidj...@aol.com Sent: Friday, September 07, 2012 4:37 PM To: time-nuts@febo.com Subject: Re: [time-nuts] Recommendations for a newbie? Hello Robert, your question is like asking which car you should buy, or which airline you should fly :) Everyone will have a different answer. But I do not recommend the Thunderbolts, it's a crab-shoot with them (different versions have different performance, the new ones are actually worse than older versions because of the temperature chip issue, the GPS is known to have lock issues, they don't work well until you spend a lot of time fine-tuning the parameters, etc etc) - that has all been discussed here ad-infinitum and you can find it in the archives. I recommend you search Ebay for HP 58503A. I just bought a number of them from a very well known seller in China, and they are absolutely superb, much better than any Rubidium unit I have tested. Much better than the Thunderbolt I have, and just slightly more expensive. He sells an entire kit for around $500, and it arrived here in less than a week (Northern California). This seller starts those units at around $260 I think. Performance you can get from these if you get a good one is: phase noise floor of around -163dBc, ADEV of 7E-013 to about 1E-012 to over 100s. Leapsecond.com has a number of test papers on these units. Caveat-emptor: there are significant unit-to-unit variations as with all GPSDO, Tom on leapsecond.com discusses this in detail. BTW: these are essentially the same unit as the Z3801A, just different software (ID string). I also have a Z3815A, and it is not even in the same class as the Z3801A/58503A. It is very noisy compared to the 58503A unit. I do not recommend the Z3815A, but it is a unique oscillator design,and some folks collect it for that oscillator. The 58503A uses a double oven version of the HP 10811A, which is a fantastic oscillator if you get a well-working one. If you want something low-cost with reasonable performance, brand new with warranty, antenna, and accessories, Jackson Labs Technologies, Inc. has the GPSTCXO eval kit for Time-Nuts special academic pricing of $300, which we believe is the lowest-cost true GPSDO (not NCO) in current production. Disclaimer: I work for them. bye, Said In a message dated 9/7/2012 13:09:24 Pacific Daylight Time, azelio.bori...@screen.it writes: Welcome aboard, yes, there is no FAQ about how to start in this hobby... should I try to implement one? Anyway, start with a Trimble Thunderbolt (aka TBolt), later you will know why it is highly recommended (direct OCXO disciplining and LH software support, mainly). I have a Z3815A with the famous (or infamous) E1938A hockey puck OCXO. They are all GPSDOs and there should not be any difference among them but, yes, there are differences in their performance and being a time-nut means test and find out. Then there are GPS disciplined Rubidiums, but take this step after the first GPSDO is correctly installed and stabilized. Start with the antenna: find a suitable place, with a 360 deg clear view of the sky, a satellite TV cable (sounds unusual, but works great). On Fri, Sep 7, 2012 at 8:52 PM, Robert Darlington rdarling...@gmail.comwrote: You want to start with a GPSDO. I like the Trimble Thunderbolt. The price is right and they're readily available. I have no experience with the HP units but they seem to be highly regarded. Rb oscillators are great for some things, but need to be calibrated. That's where the GPSDO comes in. Also, don't forget the antenna. You'll want something along these lines: http://www.ebay.com/itm/lucent-GPS-Timing-Reference-Antenna-antenne-40db-N-/ 230848464732?pt=GPS_Antennashash=item35bfa4075c#ht_2199wt_1404 Welcome aboard, and I'm apologizing in advance for how much money you'll be spending on new toys. -Bob ___ 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] Recommendations for a newbie?
And this is the key: finding out what types of measurements can be done is part of the path to be taken being a time-nut. It is better to use what already may be available in the home lab (usually every experimenter has a 'scope) and delay the purchase of the test gear. On Sat, Sep 8, 2012 at 12:51 AM, Mark Spencer mspencer12...@yahoo.cawrote: Robert, you have gotten some good advice already. With regards to rubidium standards I've bought several of the cheaper rubidium units and with the benefit of hindsight I would have put the money towards a higher quality item such as a PRS 10. There are some good write ups on line that summarize the performance of the more commonly avaliable rubidium standards. If you haven't already done so you might want to start considering what type of measurement gear you are going to use for your experiments. Before purchasing a time interval counter I was able to do quite a bit of experimenting using a dual trace oscilloscope to compare two signals. Regards Mark Spencer ___ 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] Recommendations for a newbie?
Dear Said, Good afternoon. How is the service and cosmetic condition of the HP GPS products you have bought from this source? I am considering a Z3805A just for the sake of owning one and the versatility of plug and play. Still afraid to take the plunge. Did you buy a raw unit? Or as a kit with antenna. Is that a 5V or 12V antenna? I am integrating a TBolt into a 1U rack case which also has space for a Rb oscillator for future disciplining. Got a nice TBolt monitor and would love to also include a frequency divider to get 5 and 1MHz from the TBolt. Your kind comments are welcome. Thank you. Regards, Edgardo Molina Dirección IPTEL www.iptel.net.mx T : 55 55 55202444 M : 04455 20501854 Piensa en Bits SA de CV Información anexa: CONFIDENCIALIDAD DE INFORMACION Este mensaje tiene carácter confidencial. Si usted no es el destinarario de este mensaje, le suplicamos se lo notifique al remitente mediante un correo electrónico y que borre el presente mensaje y sus anexos de su computadora sin retener una copia de los mismos. Queda estrictamente prohibido copiar este mensaje o hacer usode el para cualquier propósito o divulgar su en forma parcial o total su contenido. Gracias. NON-DISCLOSURE OF INFORMATION This email is strictly confidential and may also be privileged. If you are not the intended recipient please immediately advise the sender by replying to this e-mail and then deleting the message and its attachments from your computer without keeping a copy. It is strictly forbidden to copy it or use it for any purpose or disclose its contents to any third party. Thank you. On Sep 7, 2012, at 3:56 PM, saidj...@aol.com wrote: Robert, my bad, that seller offers 58503A units based on both Z3801A and Z3805A. The latter has a 16 channel GPS receiver, so seems to me much more desirable than the Z3801A. $50 difference. I have been testing the latter, not the former. bye, Said In a message dated 9/7/2012 13:37:52 Pacific Daylight Time, saidj...@aol.com writes: BTW: these are essentially the same unit as the Z3801A, just different software (ID string). ___ 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] Recommendations for a newbie?
Dear Azelio, Do you know how the Z3805A compares to the 58503A? Cheers! Edgardo Molina Dirección IPTEL www.iptel.net.mx T : 55 55 55202444 M : 04455 20501854 Piensa en Bits SA de CV Información anexa: CONFIDENCIALIDAD DE INFORMACION Este mensaje tiene carácter confidencial. Si usted no es el destinarario de este mensaje, le suplicamos se lo notifique al remitente mediante un correo electrónico y que borre el presente mensaje y sus anexos de su computadora sin retener una copia de los mismos. Queda estrictamente prohibido copiar este mensaje o hacer usode el para cualquier propósito o divulgar su en forma parcial o total su contenido. Gracias. NON-DISCLOSURE OF INFORMATION This email is strictly confidential and may also be privileged. If you are not the intended recipient please immediately advise the sender by replying to this e-mail and then deleting the message and its attachments from your computer without keeping a copy. It is strictly forbidden to copy it or use it for any purpose or disclose its contents to any third party. Thank you. On Sep 7, 2012, at 3:58 PM, Azelio Boriani azelio.bori...@screen.it wrote: Good one, the HP58503A, actually it is my reference at work. On Fri, Sep 7, 2012 at 10:37 PM, saidj...@aol.com wrote: Hello Robert, your question is like asking which car you should buy, or which airline you should fly :) Everyone will have a different answer. But I do not recommend the Thunderbolts, it's a crab-shoot with them (different versions have different performance, the new ones are actually worse than older versions because of the temperature chip issue, the GPS is known to have lock issues, they don't work well until you spend a lot of time fine-tuning the parameters, etc etc) - that has all been discussed here ad-infinitum and you can find it in the archives. I recommend you search Ebay for HP 58503A. I just bought a number of them from a very well known seller in China, and they are absolutely superb, much better than any Rubidium unit I have tested. Much better than the Thunderbolt I have, and just slightly more expensive. He sells an entire kit for around $500, and it arrived here in less than a week (Northern California). This seller starts those units at around $260 I think. Performance you can get from these if you get a good one is: phase noise floor of around -163dBc, ADEV of 7E-013 to about 1E-012 to over 100s. Leapsecond.com has a number of test papers on these units. Caveat-emptor: there are significant unit-to-unit variations as with all GPSDO, Tom on leapsecond.comdiscusses this in detail. BTW: these are essentially the same unit as the Z3801A, just different software (ID string). I also have a Z3815A, and it is not even in the same class as the Z3801A/58503A. It is very noisy compared to the 58503A unit. I do not recommend the Z3815A, but it is a unique oscillator design,and some folks collect it for that oscillator. The 58503A uses a double oven version of the HP 10811A, which is a fantastic oscillator if you get a well-working one. If you want something low-cost with reasonable performance, brand new with warranty, antenna, and accessories, Jackson Labs Technologies, Inc. has the GPSTCXO eval kit for Time-Nuts special academic pricing of $300, which we believe is the lowest-cost true GPSDO (not NCO) in current production. Disclaimer: I work for them. bye, Said In a message dated 9/7/2012 13:09:24 Pacific Daylight Time, azelio.bori...@screen.it writes: Welcome aboard, yes, there is no FAQ about how to start in this hobby... should I try to implement one? Anyway, start with a Trimble Thunderbolt (aka TBolt), later you will know why it is highly recommended (direct OCXO disciplining and LH software support, mainly). I have a Z3815A with the famous (or infamous) E1938A hockey puck OCXO. They are all GPSDOs and there should not be any difference among them but, yes, there are differences in their performance and being a time-nut means test and find out. Then there are GPS disciplined Rubidiums, but take this step after the first GPSDO is correctly installed and stabilized. Start with the antenna: find a suitable place, with a 360 deg clear view of the sky, a satellite TV cable (sounds unusual, but works great). On Fri, Sep 7, 2012 at 8:52 PM, Robert Darlington rdarling...@gmail.comwrote: You want to start with a GPSDO. I like the Trimble Thunderbolt. The price is right and they're readily available. I have no experience with the HP units but they seem to be highly regarded. Rb oscillators are great for some things, but need to be calibrated. That's where the GPSDO comes in. Also, don't forget the antenna. You'll want something along these lines: http://www.ebay.com/itm/lucent-GPS-Timing-Reference-Antenna-antenne-40db-N-/230848464732?pt=GPS_Antennashash=item35bfa4075c#ht_2199wt_1404 Welcome
Re: [time-nuts] Recommendations for a newbie?
Hi Edgardo, they work well for me, look brand-new, and came with power supply, rs-232 cable, and antenna. I think it's a 5V antenna. The unit had about 37000 on the lifetime. The seller has close up photos, that's what the units look like. I plugged in the power, ran GPSCon to start an Auto-Survey, and they just worked. I now get less than 3us predicted drift over 24 hours from one of the units, which is quite good according to others. I think these are pretty good for the money (free shipping on mine) but there are differences between the three units I have just like the Z3801A plots on leapsecond.com. Hope that helps, Said In a message dated 9/7/2012 17:13:22 Pacific Daylight Time, xe1...@amsat.org writes: Dear Said, Good afternoon. How is the service and cosmetic condition of the HP GPS products you have bought from this source? I am considering a Z3805A just for the sake of owning one and the versatility of plug and play. Still afraid to take the plunge. Did you buy a raw unit? Or as a kit with antenna. Is that a 5V or 12V antenna? I am integrating a TBolt into a 1U rack case which also has space for a Rb oscillator for future disciplining. Got a nice TBolt monitor and would love to also include a frequency divider to get 5 and 1MHz from the TBolt. Your kind comments are welcome. Thank you. Regards, Edgardo Molina Dirección IPTEL ___ 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] Recommendations for a newbie?
Hi Jerry, I am not familiar with those, sorry. The only complaint I would have about the 58503A units I have is that they have a bit of power supply spurs at about -130dBc. Running them from batteries would probably take care of that. Otherwise they work great for me and provide both great ADEV and very good phase noise at the same time, what else can one ask for $550.. But again, there may be large unit-to-unit variations as Tom has found out, and I may have been lucky with the units I received.. bye, Said In a message dated 9/7/2012 15:55:04 Pacific Daylight Time, jster...@att.net writes: Said, Where do you rank the Samsung GCRU-D among these? Jerry ___ 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] Recommendations for a newbie?
Dear Said, Thank you for your kind explanation. I will be considering such a purchase in the near future. I will keep you informed about my experiences. You have a nice evening. Regards, Edgardo Molina Dirección IPTEL www.iptel.net.mx T : 55 55 55202444 M : 04455 20501854 Piensa en Bits SA de CV Información anexa: CONFIDENCIALIDAD DE INFORMACION Este mensaje tiene carácter confidencial. Si usted no es el destinarario de este mensaje, le suplicamos se lo notifique al remitente mediante un correo electrónico y que borre el presente mensaje y sus anexos de su computadora sin retener una copia de los mismos. Queda estrictamente prohibido copiar este mensaje o hacer usode el para cualquier propósito o divulgar su en forma parcial o total su contenido. Gracias. NON-DISCLOSURE OF INFORMATION This email is strictly confidential and may also be privileged. If you are not the intended recipient please immediately advise the sender by replying to this e-mail and then deleting the message and its attachments from your computer without keeping a copy. It is strictly forbidden to copy it or use it for any purpose or disclose its contents to any third party. Thank you. On Sep 7, 2012, at 8:14 PM, saidj...@aol.com wrote: Hi Edgardo, they work well for me, look brand-new, and came with power supply, rs-232 cable, and antenna. I think it's a 5V antenna. The unit had about 37000 on the lifetime. The seller has close up photos, that's what the units look like. I plugged in the power, ran GPSCon to start an Auto-Survey, and they just worked. I now get less than 3us predicted drift over 24 hours from one of the units, which is quite good according to others. I think these are pretty good for the money (free shipping on mine) but there are differences between the three units I have just like the Z3801A plots on leapsecond.com. Hope that helps, Said In a message dated 9/7/2012 17:13:22 Pacific Daylight Time, xe1...@amsat.org writes: Dear Said, Good afternoon. How is the service and cosmetic condition of the HP GPS products you have bought from this source? I am considering a Z3805A just for the sake of owning one and the versatility of plug and play. Still afraid to take the plunge. Did you buy a raw unit? Or as a kit with antenna. Is that a 5V or 12V antenna? I am integrating a TBolt into a 1U rack case which also has space for a Rb oscillator for future disciplining. Got a nice TBolt monitor and would love to also include a frequency divider to get 5 and 1MHz from the TBolt. Your kind comments are welcome. Thank you. Regards, Edgardo Molina Dirección IPTEL ___ 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.
