[time-nuts] Confusion over Thunderbolt - noob is going crazy
I hope I don't get yelled at for asking this question. I honestly looked everywhere and still can't get this. I have several GPSDO but I don't have a TRUE Thunderbolt. I want one. So I started looking. There seem to be infinite variations of them. So far (I have been looking for a week), there are no good summary (or even a summary) of various types and how they are different. I know there is a thin type that looks to be 1" or so thick, and thick type that is about double that.I know thick type can have blue label with current Tbolt E, or red label (read somewhere this is an earlier one?) I know there is a type that contains inferior oven and better one. (Marked Trimble)I know there is a type with F connector for antenna, and there is one with BNC.I know there is an early type and late type. (I don't know how to tell)I know the latest one is T-boltE, which is not necessary similar to earlier ones.I know there is a type that requires single voltage and 3 sources. What I don't know is: How many different types are there.Any particular one to avoid? I know there were some experiment done with replacing OCXO of earliest type.Why form factor change? OCXO does not seem to be any tallerSpending $1500 for new one is out of question, but price seems to vary from $150 to $500 for used ones. Since most of them come from China, I'd think they are reclaimed equipment. Is this assumption right? Any reliable source? I am a bit skeptical with the market the way it is.Are they all telecom quality? Thank you very much. --- (Mr.) Taka Kamiya KB4EMF / ex JF2DKG ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
[time-nuts] Confusion over Thunderbolt - noob is going crazy
Basically there is only one Thunderbolt. There are 2 firmware versions (2.2 & 3.0) and some of the earlier firmware version had a Piezo branded oscillator rather than the Trimble branded one and the Trimble one is somewhat better. The thick Thunderbolt package has a switching power supply mounted on top of the Thunderbolt that allows one voltage to supply the unit rather than the +5/+12/-12 used by the Thunderbolt proper. The sellers of the one with the power supply mounted on top seem to ask way more for the package than the cost of the included power supply would warrant. I have one of the 2.2 firmware version with a Trimble branded OCXO that I have used for years and it works perfectly for my use. Of the over 200 units I have sold there were only a couple of the 2.2 firmware versions and no Piezo OCXOs in all those. I’ve never seen or heard of a BNC antenna connector. Internal to the wireless locator where these Thunderbolt were used there was a cable to go from the type F connector on the Thunderbolt to the TNC connector on the rear panel of the locator. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Confusion over Thunderbolt - noob is going crazy
Hi “Thunderbolt” is the name Trimble uses for their line of GPSDO’s. They have used it for almost 30 years. They have had at least a dozen different models within their line of GPSDO’s. Back about ten to fifteen years ago, a 911 location system started to be scrapped out. It was being replaced by newer / better / whatever systems. That location system happened to use a slightly customized version of one of the Trimble GPSDO’s. Like all the rest, it was called a Thunderbolt. They hit the market in large volume and prices dropped. Also some nice people actually did some work on group buys to help sort things out. All of that got a lot of attention focused on them. Indeed after some poking at them, some turned out to be a bit better than others. Units with date codes past about 2005 or so have better OCXO’s in them than units before about 2000. In-between those dates, the OCXO’s got progressively better. Firmware wise, things got updated over the years. At some point the temperature sensor IC’s went a bit sideways and the temperature readout suffered. The China reclamation process is not kind to gear. It often sits out in the rain for quite a while. That does not do the gear any good. The level of “testing” done by any of the sellers is superficial at best. Even “back in the good old days” one might find one in five units with a problem. Indeed, it’s quite possible that after sitting in a dusty corner of the basement, some previously good units now have issues. Stuff happens. The unit that gets all the press has two BNC connectors and an F connector out one end and a 9 pin serial port. There is a power connector coming out the top of the unit. It is about an inch thick. The enclosure is not painted on most units. If the cover is on the unit, there is no way to see what’s on the PC board. A “real” unit comes with the cover / enclosure. The only easily read label on the PC board is the label that shipped on the OCXO when it went out to Trimble. The red “Piezo” labels are early OCXO’s. The later OCXO’s have slightly off white labels on them. If you get a unit with a problem, there are no schematics. There also are no firmware images. There is information on replacing the temperature sensor IC and on replacing the RS-232 driver chip. They are the “original” unit that worked with LH so support there is very good. Performance wise they are good units, but hardly unique. There are a lot of devices out there that perform worse. A properly designed Rb based unit would beat them in most respects. Bob > On Nov 14, 2019, at 11:02 PM, Taka Kamiya via time-nuts > wrote: > > I hope I don't get yelled at for asking this question. I honestly looked > everywhere and still can't get this. > I have several GPSDO but I don't have a TRUE Thunderbolt. I want one. So I > started looking. There seem to be infinite variations of them. So far (I > have been looking for a week), there are no good summary (or even a summary) > of various types and how they are different. > I know there is a thin type that looks to be 1" or so thick, and thick type > that is about double that.I know thick type can have blue label with current > Tbolt E, or red label (read somewhere this is an earlier one?) > I know there is a type that contains inferior oven and better one. (Marked > Trimble)I know there is a type with F connector for antenna, and there is one > with BNC.I know there is an early type and late type. (I don't know how to > tell)I know the latest one is T-boltE, which is not necessary similar to > earlier ones.I know there is a type that requires single voltage and 3 > sources. > What I don't know is: > How many different types are there.Any particular one to avoid? I know there > were some experiment done with replacing OCXO of earliest type.Why form > factor change? OCXO does not seem to be any tallerSpending $1500 for new > one is out of question, but price seems to vary from $150 to $500 for used > ones. Since most of them come from China, I'd think they are reclaimed > equipment. Is this assumption right? > Any reliable source? I am a bit skeptical with the market the way it is.Are > they all telecom quality? > > Thank you very much. > > > --- > (Mr.) Taka Kamiya > KB4EMF / ex JF2DKG > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Confusion over Thunderbolt - noob is going crazy
Taka - The majority of the surplus GPSDO units come from the mobile/cellular telecommunication companies since the late 1990s. Surplus equipment occurs due to Service advances (2G—>3G—>4G/LTE—>5G), Technology upgrades/obsolescence, and Consolidation/merger of telecom companies. == NO Distinct Advantage in owning the Trimble Thunderbolt models versus other options, some would note a few disadvantages (now 10 years later, like 1024-week rollover). == A large number of Trimble Thunderbolt GPS Disciplined Oscillators (GPSDO) appeared on the surplus market in 2007 and 2008. Majority of these were the “THIN Model” (no internal DC-DC converter). At that time (2008) TAPR Time-Nuts had a Group Buy, and offered a KIT (~ $225). Tom Van Baak (tvb) and other members of Time-Nuts tested units and packaged these with a tri-voltage (+5, +12, -12) power supply for Group Buy participants. http://www.leapsecond.com/pages/tapr-tbolt/ W6AER built (DIY) this Rack Case for his surplus Thunderbolt & power supply. https://w6aer.com/10mhz-gps-disciplined-oscillator-gpsdo-trimble-thunderbolt/ = The RED Thunderbolt model has a Larger case because it contains the SMPS (24V to Tri-Voltage) as well as the GPSDO (THICK model). http://trl.trimble.com/docushare/dsweb/Get/Document-10015/ This specific model is no longer mfg. or supported by Trimble (no firmware updates provided). Surplus “Red” units have appeared from 911 telephone centers (past 5 years), since the RED model does not handle the 1024-week rollover. The “cheapest” has been ~$250 (2018 price, I paid) for a surplus unit from a Pennsylvania 911 center. https://en.wikipedia.org/wiki/GPS_Week_Number_Rollover The Lady Heather software (Mark Sims) “notes & corrects” the 1024-week rollover occurrence with these Trimble units, on its computer display. ANY OTHER Solution would also have to “Correct” for the 1024-week rollover. — The BLUE Thunderbolt E model is Current Trimble Production ($$), hence RARELY seen as Surplus. Trimble refreshed their hardware, simplifying design (newer components). http://trl.trimble.com/docushare/dsweb/Get/Document-383329/ Trimble Thunderbolt-E Product Page https://www.trimble.com/Timing/thunderbolt-e.aspx = THUNDERBOLT Frequently Asked Questions (from Group Buy, a decade ago). http://www.ko4bb.com/getsimple/index.php?id=time-nuts-thunderbolt-gpsdo-group-buy g. beat, w9gb chicago == Date: Fri, 15 Nov 2019 04:02:56 + (UTC) From: Taka Kamiya To: Time Nuts Group Subject: [time-nuts] Confusion over Thunderbolt - noob is going crazy I have several GPSDO, BUT I don't have a TRUE Trimble Thunderbolt. I want one. There seem to be infinite variations of them. So far (I have been looking for a week), there are no good summary (or even a summary) of various types and how they are different. I know there is a thin type that looks to be 1" or so thick, and thick type that is about double that. I know one model has a Blue label (Thunderbolt E) and an earlier model had a Red Label (Thunderbolt). I know there are differences in the Internal Crystal Oscillator/Oven. Spending $1500 for new one is out of question, but price seems to vary from $150 to $500 for used ones. Since most of these surplus units now come from China, I'd think they are reclaimed equipment. Is this assumption right? Any reliable source?? I am a bit skeptical with the surplus market the way it is. Are they all telecom quality?? Thank you very much. -- (Mr.) Taka Kamiya KB4EMF / ex JF2DKG ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Confusion over Thunderbolt - noob is going crazy
You mentioned "this particular model," referring to the RED version, is no longer manufactured or supported. (no firmware support) But does that mean ones OLDER than that is still supported for firmware upgrades? Where do I go on Trimble's website? There was nothing on firmware under "support". Thank you for helping out this noob! --- (Mr.) Taka Kamiya KB4EMF / ex JF2DKG On Friday, November 15, 2019, 2:48:00 PM EST, Gregory Beat via time-nuts wrote: Taka - The majority of the surplus GPSDO units come from the mobile/cellular telecommunication companies since the late 1990s. Surplus equipment occurs due to Service advances (2G—>3G—>4G/LTE—>5G), Technology upgrades/obsolescence, and Consolidation/merger of telecom companies. == NO Distinct Advantage in owning the Trimble Thunderbolt models versus other options, some would note a few disadvantages (now 10 years later, like 1024-week rollover). == A large number of Trimble Thunderbolt GPS Disciplined Oscillators (GPSDO) appeared on the surplus market in 2007 and 2008. Majority of these were the “THIN Model” (no internal DC-DC converter). At that time (2008) TAPR Time-Nuts had a Group Buy, and offered a KIT (~ $225). Tom Van Baak (tvb) and other members of Time-Nuts tested units and packaged these with a tri-voltage (+5, +12, -12) power supply for Group Buy participants. http://www.leapsecond.com/pages/tapr-tbolt/ W6AER built (DIY) this Rack Case for his surplus Thunderbolt & power supply. https://w6aer.com/10mhz-gps-disciplined-oscillator-gpsdo-trimble-thunderbolt/ = The RED Thunderbolt model has a Larger case because it contains the SMPS (24V to Tri-Voltage) as well as the GPSDO (THICK model). http://trl.trimble.com/docushare/dsweb/Get/Document-10015/ This specific model is no longer mfg. or supported by Trimble (no firmware updates provided). Surplus “Red” units have appeared from 911 telephone centers (past 5 years), since the RED model does not handle the 1024-week rollover. The “cheapest” has been ~$250 (2018 price, I paid) for a surplus unit from a Pennsylvania 911 center. https://en.wikipedia.org/wiki/GPS_Week_Number_Rollover The Lady Heather software (Mark Sims) “notes & corrects” the 1024-week rollover occurrence with these Trimble units, on its computer display. ANY OTHER Solution would also have to “Correct” for the 1024-week rollover. — The BLUE Thunderbolt E model is Current Trimble Production ($$), hence RARELY seen as Surplus. Trimble refreshed their hardware, simplifying design (newer components). http://trl.trimble.com/docushare/dsweb/Get/Document-383329/ Trimble Thunderbolt-E Product Page https://www.trimble.com/Timing/thunderbolt-e.aspx = THUNDERBOLT Frequently Asked Questions (from Group Buy, a decade ago). http://www.ko4bb.com/getsimple/index.php?id=time-nuts-thunderbolt-gpsdo-group-buy g. beat, w9gb chicago == Date: Fri, 15 Nov 2019 04:02:56 + (UTC) From: Taka Kamiya To: Time Nuts Group Subject: [time-nuts] Confusion over Thunderbolt - noob is going crazy I have several GPSDO, BUT I don't have a TRUE Trimble Thunderbolt. I want one. There seem to be infinite variations of them. So far (I have been looking for a week), there are no good summary (or even a summary) of various types and how they are different. I know there is a thin type that looks to be 1" or so thick, and thick type that is about double that. I know one model has a Blue label (Thunderbolt E) and an earlier model had a Red Label (Thunderbolt). I know there are differences in the Internal Crystal Oscillator/Oven. Spending $1500 for new one is out of question, but price seems to vary from $150 to $500 for used ones. Since most of these surplus units now come from China, I'd think they are reclaimed equipment. Is this assumption right? Any reliable source?? I am a bit skeptical with the surplus market the way it is. Are they all telecom quality?? Thank you very much. -- (Mr.) Taka Kamiya KB4EMF / ex JF2DKG ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Confusion over Thunderbolt - noob is going crazy
Thank you. The BNC port one may be a custom job. I know they OEM'd for few companies. Since I have so many GPSDOs, I want one "master" unit. So I started looking what appear to be the most commonly used type. By the way did you ever get to tame the severe jitter of Symmetricon version of GPSTM? I was so pleased with the Trimble version that I bought 6 of this Symmetricon version. As it is, they are useless. --- (Mr.) Taka Kamiya KB4EMF / ex JF2DKG On Friday, November 15, 2019, 10:51:11 AM EST, Arthur Dent wrote: Basically there is only one Thunderbolt. There are 2 firmware versions (2.2 & 3.0) and some of the earlier firmware version had a Piezo branded oscillator rather than the Trimble branded one and the Trimble one is somewhat better. The thick Thunderbolt package has a switching power supply mounted on top of the Thunderbolt that allows one voltage to supply the unit rather than the +5/+12/-12 used by the Thunderbolt proper. The sellers of the one with the power supply mounted on top seem to ask way more for the package than the cost of the included power supply would warrant. I have one of the 2.2 firmware version with a Trimble branded OCXO that I have used for years and it works perfectly for my use. Of the over 200 units I have sold there were only a couple of the 2.2 firmware versions and no Piezo OCXOs in all those. I’ve never seen or heard of a BNC antenna connector. Internal to the wireless locator where these Thunderbolt were used there was a cable to go from the type F connector on the Thunderbolt to the TNC connector on the rear panel of the locator. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Confusion over Thunderbolt - noob is going crazy
Hi None of the GPSDO’s commonly available on eBay have firmware updates available for them. They also pretty much all do not have schematics or service manuals. It is rare to find a model that has an operating manual. Bob > On Nov 15, 2019, at 3:20 PM, Taka Kamiya via time-nuts > wrote: > > You mentioned "this particular model," referring to the RED version, is no > longer manufactured or supported. (no firmware support) But does that mean > ones OLDER than that is still supported for firmware upgrades? Where do I go > on Trimble's website? There was nothing on firmware under "support". > > Thank you for helping out this noob! > > > --- > (Mr.) Taka Kamiya > KB4EMF / ex JF2DKG > > >On Friday, November 15, 2019, 2:48:00 PM EST, Gregory Beat via time-nuts > wrote: > > Taka - > > The majority of the surplus GPSDO units come from the mobile/cellular > telecommunication companies since the late 1990s. Surplus equipment occurs > due to Service advances (2G—>3G—>4G/LTE—>5G), Technology > upgrades/obsolescence, and Consolidation/merger of telecom companies. > == > NO Distinct Advantage in owning the Trimble Thunderbolt models versus other > options, > some would note a few disadvantages (now 10 years later, like 1024-week > rollover). > == > A large number of Trimble Thunderbolt GPS Disciplined Oscillators (GPSDO) > appeared on the surplus market in 2007 and 2008. Majority of these were the > “THIN Model” (no internal DC-DC converter). > > At that time (2008) TAPR Time-Nuts had a Group Buy, and offered a KIT (~ > $225). > Tom Van Baak (tvb) and other members of Time-Nuts tested units and packaged > these with a tri-voltage (+5, +12, -12) power supply for Group Buy > participants. > http://www.leapsecond.com/pages/tapr-tbolt/ > > W6AER built (DIY) this Rack Case for his surplus Thunderbolt & power supply. > https://w6aer.com/10mhz-gps-disciplined-oscillator-gpsdo-trimble-thunderbolt/ > = > The RED Thunderbolt model has a Larger case because it contains the SMPS (24V > to Tri-Voltage) as well as the GPSDO (THICK model). > http://trl.trimble.com/docushare/dsweb/Get/Document-10015/ > This specific model is no longer mfg. or supported by Trimble (no firmware > updates provided). Surplus “Red” units have appeared from 911 telephone > centers (past 5 years), since the RED model does not handle the 1024-week > rollover. The “cheapest” has been ~$250 (2018 price, I paid) for a surplus > unit from a Pennsylvania 911 center. > https://en.wikipedia.org/wiki/GPS_Week_Number_Rollover > The Lady Heather software (Mark Sims) “notes & corrects” the 1024-week > rollover occurrence with these Trimble units, on its computer display. > ANY OTHER Solution would also have to “Correct” for the 1024-week rollover. > — > The BLUE Thunderbolt E model is Current Trimble Production ($$), hence RARELY > seen as Surplus. Trimble refreshed their hardware, simplifying design (newer > components). > http://trl.trimble.com/docushare/dsweb/Get/Document-383329/ > Trimble Thunderbolt-E Product Page > https://www.trimble.com/Timing/thunderbolt-e.aspx > = > THUNDERBOLT Frequently Asked Questions (from Group Buy, a decade ago). > http://www.ko4bb.com/getsimple/index.php?id=time-nuts-thunderbolt-gpsdo-group-buy > > g. beat, w9gb > chicago > == > Date: Fri, 15 Nov 2019 04:02:56 + (UTC) > From: Taka Kamiya > To: Time Nuts Group > Subject: [time-nuts] Confusion over Thunderbolt - noob is going crazy > > I have several GPSDO, BUT I don't have a TRUE Trimble Thunderbolt. I want > one. > There seem to be infinite variations of them. So far (I have been looking > for a week), there are no good summary (or even a summary) of various types > and how they are different. > I know there is a thin type that looks to be 1" or so thick, and thick type > that is about double that. I know one model has a Blue label (Thunderbolt E) > and an earlier model had a Red Label (Thunderbolt). > I know there are differences in the Internal Crystal Oscillator/Oven. > > Spending $1500 for new one is out of question, but price seems to vary from > $150 to $500 for used ones. Since most of these surplus units now come from > China, I'd think they are reclaimed equipment. Is this assumption right? > Any reliable source?? > I am a bit skeptical with the surplus market the way it is. Are they all > telecom quality?? > Thank you very much. > -- > (Mr.) Taka Kamiya > KB4EMF / ex JF2DKG > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To u
Re: [time-nuts] Confusion over Thunderbolt - noob is going crazy
As far as I'm aware, the Thunderbolt E models are the only one ones with firmware new enough to handle the WNRO. Even the single-oven OXCO version of the E is EOL, but it at least is new enough. I'm also pretty sure the Es have BNC connectors, at least both of mine do. -Dustin On Fri, Nov 15, 2019 at 2:30 PM Taka Kamiya via time-nuts wrote: > > You mentioned "this particular model," referring to the RED version, is no > longer manufactured or supported. (no firmware support) But does that mean > ones OLDER than that is still supported for firmware upgrades? Where do I go > on Trimble's website? There was nothing on firmware under "support". > > Thank you for helping out this noob! > > > --- > (Mr.) Taka Kamiya > KB4EMF / ex JF2DKG > > > On Friday, November 15, 2019, 2:48:00 PM EST, Gregory Beat via time-nuts > wrote: > > Taka - > > The majority of the surplus GPSDO units come from the mobile/cellular > telecommunication companies since the late 1990s. Surplus equipment occurs > due to Service advances (2G—>3G—>4G/LTE—>5G), Technology > upgrades/obsolescence, and Consolidation/merger of telecom companies. > == > NO Distinct Advantage in owning the Trimble Thunderbolt models versus other > options, > some would note a few disadvantages (now 10 years later, like 1024-week > rollover). > == > A large number of Trimble Thunderbolt GPS Disciplined Oscillators (GPSDO) > appeared on the surplus market in 2007 and 2008. Majority of these were the > “THIN Model” (no internal DC-DC converter). > > At that time (2008) TAPR Time-Nuts had a Group Buy, and offered a KIT (~ > $225). > Tom Van Baak (tvb) and other members of Time-Nuts tested units and packaged > these with a tri-voltage (+5, +12, -12) power supply for Group Buy > participants. > http://www.leapsecond.com/pages/tapr-tbolt/ > > W6AER built (DIY) this Rack Case for his surplus Thunderbolt & power supply. > https://w6aer.com/10mhz-gps-disciplined-oscillator-gpsdo-trimble-thunderbolt/ > = > The RED Thunderbolt model has a Larger case because it contains the SMPS (24V > to Tri-Voltage) as well as the GPSDO (THICK model). > http://trl.trimble.com/docushare/dsweb/Get/Document-10015/ > This specific model is no longer mfg. or supported by Trimble (no firmware > updates provided). Surplus “Red” units have appeared from 911 telephone > centers (past 5 years), since the RED model does not handle the 1024-week > rollover. The “cheapest” has been ~$250 (2018 price, I paid) for a surplus > unit from a Pennsylvania 911 center. > https://en.wikipedia.org/wiki/GPS_Week_Number_Rollover > The Lady Heather software (Mark Sims) “notes & corrects” the 1024-week > rollover occurrence with these Trimble units, on its computer display. > ANY OTHER Solution would also have to “Correct” for the 1024-week rollover. > — > The BLUE Thunderbolt E model is Current Trimble Production ($$), hence RARELY > seen as Surplus. Trimble refreshed their hardware, simplifying design (newer > components). > http://trl.trimble.com/docushare/dsweb/Get/Document-383329/ > Trimble Thunderbolt-E Product Page > https://www.trimble.com/Timing/thunderbolt-e.aspx > = > THUNDERBOLT Frequently Asked Questions (from Group Buy, a decade ago). > http://www.ko4bb.com/getsimple/index.php?id=time-nuts-thunderbolt-gpsdo-group-buy > > g. beat, w9gb > chicago > == > Date: Fri, 15 Nov 2019 04:02:56 + (UTC) > From: Taka Kamiya > To: Time Nuts Group > Subject: [time-nuts] Confusion over Thunderbolt - noob is going crazy > > I have several GPSDO, BUT I don't have a TRUE Trimble Thunderbolt. I want > one. > There seem to be infinite variations of them. So far (I have been looking > for a week), there are no good summary (or even a summary) of various types > and how they are different. > I know there is a thin type that looks to be 1" or so thick, and thick type > that is about double that. I know one model has a Blue label (Thunderbolt E) > and an earlier model had a Red Label (Thunderbolt). > I know there are differences in the Internal Crystal Oscillator/Oven. > > Spending $1500 for new one is out of question, but price seems to vary from > $150 to $500 for used ones. Since most of these surplus units now come from > China, I'd think they are reclaimed equipment. Is this assumption right? > Any reliable source?? > I am a bit skeptical with the surplus market the way it is. Are they all > telecom quality?? > Thank you very much. > -- > (Mr.) Taka Kamiya > KB4EMF / ex JF2DKG > ___ > time-nuts mailing list -- time-n
