[time-nuts] eBay GPS antenna test results.
Bob wrote: Is it labeled 3.3 to 18V on the antenna? No, the writing on the antenna is all Chinese. The specs published on eBay state that it is. ___ 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] Symmetricom 58532A GPS Antenna : Launch3 Surplus
3M has a product called Cold Shrink tubing. It is designed to seal high voltage, etc cables in buried installations. It is a silicone (?) rubber stretched over a collapsable polyethylene core. You run the cable through the core and pull on a tab which unwinds the core and the stretched silicone collapses and forms a water tight seal. I have not used it to seal cables, but have used to replace polyurethane coatings on printer platens (Tek TDR thermal printers and HP9100 calculator electrostatic printers) that have turned to goo. ___ 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] eBay GPS antenna test results.
I would surmise that the antenna has (or rather had) a protection network to protect against voltage spikes or surges. Your description of events seems consistent with an triggered SCR crowbar circuit, and the 2nd attempt at the higher current limit shorted the SCR. Note that this may not have been a regular SCR, but perhaps a NPN/PNP pair hooked up to emulate an SCR. If you can find evidence of such a circuit, it may be replaceable or simply removable, leaving the antenna fully functional. Assuming this works, do keep the supply voltage down to something reasonable like 5 or 6 volts. Excess voltage will result in unneeded heat generation in whatever regulator the antenna uses, shortening its life. Dana On Fri, Feb 9, 2018 at 5:00 PM, Dr. David Kirkby < drkir...@kirkbymicrowave.co.uk> wrote: > On 9 February 2018 at 21:43, John Green wrote: > > > To those who doubted that the antenna was actually a 3.3 to 18 volt > design, > > it seems you were correct. Today, I hooked it up to a variable power > supply > > and slowly raised the DC voltage fed to the antenna. It began to pull > > current at about 2.9 volts and at 3.3 volts, took about 40 mA. I > continued > > to slowly raise the voltage. At about 7.5 volts, the current suddenly > > dropped to 10 mA. At just below 12 volts, it suddenly increased to 80 mA > > and the supply went into current limit. I increased the current limit to > > 130 mA and repeated the exercise. Everything went as above until I > reached > > 12 volts and the current went to 130 mA and the supply went into current > > limit. Lowering the voltage didn't lower the current. I disconnected it, > > waited a minute, and tried again. Yep, shorted. It would have worked well > > with the T bolt, but would have blown anyway if I tried to use it with my > > 12 volt supply and bias T. I guess I will get inside it somehow to see if > > it can be repaired. My first attempt ended in failure. I guess I need a > > bigger screwdriver with which to pry the top off. I am going to contact > the > > seller and tell them it was not as advertised. I kind of doubt that will > > get me anything, but it won't hurt to try. There is a saying about > > experience being a cruel teacher. You get the results first, and the > lesson > > after. Oh well. > > > > > You should not open it up, but open an eBay case for item not as described. > If it said it would do 3-18 V, but does not, then its not as described, and > you should get your money back. The chances are the seller will not want to > arrange collection, so you will probably get to keep it anyway. But you > should get a refund before opening it up. > > Dave > ___ > 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] Symmetricom 58532A GPS Antenna : Launch3 Surplus
It's called 'adhesive lined heatshrink'. Yes, it's available, though a reel of the Good Stuff (Raychem) costs a small fortune. They also make custom boots to fit various standard connectors. Probably best bought as surplus or from a trusted seller who bought reels from military, autosport or aircraft industries. The short lengths available on ebay are often inferior grades. A heatshrinking tape is also available. Hams tend to use self-amalgamating tape, as Phil recommended. On Sat, Feb 10, 2018 at 12:41 AM, Hal Murray wrote: > > li...@philpem.me.uk said: > > Generally speaking, you can seal most RF connectors quite nicely with a > few > > layers of self-amalgamating tape and a layer of PVC tape over the top of > > that (to protect from UV). > > Many years ago, I picked up a chunk of scrap the local cable TV installer > had > left on the ground underneath the utility pole out in front of my house. > It > was a chunk of industrial strength shrink wrap with a layer of goop on the > inside. > > Is that stuff available in small quantities? Would the antenna withstand > the > necessary heat? > > How do hams seal antenna connectors? > > > -- > These are my opinions. I hate spam. > > > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/ > mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Symmetricom 58532A GPS Antenna : Launch3 Surplus
Hi There are tapes designed for waterproofing things like coax connectors. Bob > On Feb 9, 2018, at 7:41 PM, Hal Murray wrote: > > > li...@philpem.me.uk said: >> Generally speaking, you can seal most RF connectors quite nicely with a few >> layers of self-amalgamating tape and a layer of PVC tape over the top of >> that (to protect from UV). > > Many years ago, I picked up a chunk of scrap the local cable TV installer had > left on the ground underneath the utility pole out in front of my house. It > was a chunk of industrial strength shrink wrap with a layer of goop on the > inside. > > Is that stuff available in small quantities? Would the antenna withstand the > necessary heat? > > How do hams seal antenna connectors? > > > -- > These are my opinions. I hate spam. > > > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Symmetricom 58532A GPS Antenna : Launch3 Surplus
li...@philpem.me.uk said: > Generally speaking, you can seal most RF connectors quite nicely with a few > layers of self-amalgamating tape and a layer of PVC tape over the top of > that (to protect from UV). Many years ago, I picked up a chunk of scrap the local cable TV installer had left on the ground underneath the utility pole out in front of my house. It was a chunk of industrial strength shrink wrap with a layer of goop on the inside. Is that stuff available in small quantities? Would the antenna withstand the necessary heat? How do hams seal antenna connectors? -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Symmetricom 58532A GPS Antenna : Launch3 Surplus
On 06/02/18 22:21, Angus via time-nuts wrote: > On Tue, 6 Feb 2018 14:54:23 -0500, you wrote: > >> 3) its designed for continuous outdoor use (connector is well shielded etc) > > That's something that has always baffled me - the number of antennas > which the manufacturers claim are suitable for long term outdoor use > that have connectors which are impossible to seal without large > quantities of sealant or whatever. Generally speaking, you can seal most RF connectors quite nicely with a few layers of self-amalgamating tape and a layer of PVC tape over the top of that (to protect from UV). Practically speaking, if the antenna is mounted on the top of a pole, >95% of the rainwater is going to run down the side of the antenna and drip off the edge (assuming something shaped roughly like a PCTel 26dB timing antenna). The seals are more use if the antenna is mounted on a flat surface. -- Phil. li...@philpem.me.uk http://www.philpem.me.uk/ ___ 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] Receiving the MSF time signal on cheap radio modules
On 07/02/18 01:16, Bob kb8tq wrote: >> MSF disciplined oscillator?! I don't trust these receivers to any better >> than about the 20ms mark, so such a disciplined oscillator would have quite >> a long integration time! > > Once upon a time, that *was* how people did disciplined oscillators. Part of > the > answer to “how?” is that their target accuracies were not as tight as what we > now > think of as normal. I was under the impression the Radio Four carrier (198kHz ex 200kHz) was the old "frequency standard of choice" in the UK, prior to GPS. I don't recall anyone using MSF for much other than "what time is it, to maybe the nearest second?". Though I do recall John Becker of EPE magazine did a nifty little millennium countdown clock using MSF as a base. -- Phil. phil...@philpem.me.uk http://www.philpem.me.uk/ ___ 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] eBay GPS antenna test results.
On 9 February 2018 at 21:43, John Green wrote: > To those who doubted that the antenna was actually a 3.3 to 18 volt design, > it seems you were correct. Today, I hooked it up to a variable power supply > and slowly raised the DC voltage fed to the antenna. It began to pull > current at about 2.9 volts and at 3.3 volts, took about 40 mA. I continued > to slowly raise the voltage. At about 7.5 volts, the current suddenly > dropped to 10 mA. At just below 12 volts, it suddenly increased to 80 mA > and the supply went into current limit. I increased the current limit to > 130 mA and repeated the exercise. Everything went as above until I reached > 12 volts and the current went to 130 mA and the supply went into current > limit. Lowering the voltage didn't lower the current. I disconnected it, > waited a minute, and tried again. Yep, shorted. It would have worked well > with the T bolt, but would have blown anyway if I tried to use it with my > 12 volt supply and bias T. I guess I will get inside it somehow to see if > it can be repaired. My first attempt ended in failure. I guess I need a > bigger screwdriver with which to pry the top off. I am going to contact the > seller and tell them it was not as advertised. I kind of doubt that will > get me anything, but it won't hurt to try. There is a saying about > experience being a cruel teacher. You get the results first, and the lesson > after. Oh well. > You should not open it up, but open an eBay case for item not as described. If it said it would do 3-18 V, but does not, then its not as described, and you should get your money back. The chances are the seller will not want to arrange collection, so you will probably get to keep it anyway. But you should get a refund before opening it up. Dave ___ 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] eBay GPS antenna test results.
Hi Is it labeled 3.3 to 18V on the antenna? Bob > On Feb 9, 2018, at 4:43 PM, John Green wrote: > > To those who doubted that the antenna was actually a 3.3 to 18 volt design, > it seems you were correct. Today, I hooked it up to a variable power supply > and slowly raised the DC voltage fed to the antenna. It began to pull > current at about 2.9 volts and at 3.3 volts, took about 40 mA. I continued > to slowly raise the voltage. At about 7.5 volts, the current suddenly > dropped to 10 mA. At just below 12 volts, it suddenly increased to 80 mA > and the supply went into current limit. I increased the current limit to > 130 mA and repeated the exercise. Everything went as above until I reached > 12 volts and the current went to 130 mA and the supply went into current > limit. Lowering the voltage didn't lower the current. I disconnected it, > waited a minute, and tried again. Yep, shorted. It would have worked well > with the T bolt, but would have blown anyway if I tried to use it with my > 12 volt supply and bias T. I guess I will get inside it somehow to see if > it can be repaired. My first attempt ended in failure. I guess I need a > bigger screwdriver with which to pry the top off. I am going to contact the > seller and tell them it was not as advertised. I kind of doubt that will > get me anything, but it won't hurt to try. There is a saying about > experience being a cruel teacher. You get the results first, and the lesson > after. Oh well. > ___ > 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] eBay GPS antenna test results.
To those who doubted that the antenna was actually a 3.3 to 18 volt design, it seems you were correct. Today, I hooked it up to a variable power supply and slowly raised the DC voltage fed to the antenna. It began to pull current at about 2.9 volts and at 3.3 volts, took about 40 mA. I continued to slowly raise the voltage. At about 7.5 volts, the current suddenly dropped to 10 mA. At just below 12 volts, it suddenly increased to 80 mA and the supply went into current limit. I increased the current limit to 130 mA and repeated the exercise. Everything went as above until I reached 12 volts and the current went to 130 mA and the supply went into current limit. Lowering the voltage didn't lower the current. I disconnected it, waited a minute, and tried again. Yep, shorted. It would have worked well with the T bolt, but would have blown anyway if I tried to use it with my 12 volt supply and bias T. I guess I will get inside it somehow to see if it can be repaired. My first attempt ended in failure. I guess I need a bigger screwdriver with which to pry the top off. I am going to contact the seller and tell them it was not as advertised. I kind of doubt that will get me anything, but it won't hurt to try. There is a saying about experience being a cruel teacher. You get the results first, and the lesson after. Oh well. ___ 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] Looking for Datum TymServe 2000 (TS2000) manual
Skip - The Trimble Acutime 2000 outdoor antenna http://www.n4iqt.com/trimble/Acutime2000.pdf looks identical to the Trimble Palisade GPS antenna. http://dc2light.co.uk/PALISADE-Manual.zip Mark, GM4ISM had surplus Palisade antennas, at one time. He noted differential RS-422 configuration and TSIP output. He has Trimble programs on his web page. http://dc2light.co.uk/GPS_ref.htm Andy, G4JNT wrote a PIC conversion (Trimble—> NEMA) for Mark’s project. http://www.g4jnt.com/pics.htm Palisade uses Deutsch IMC-200 12-pin circular connector, part number: IMC26-2212 http://uk.farnell.com/deutsch/imc26-2212x/plug-in-line-12-way/dp/1019239 greg, w9gb ==Original Message== From: Skip Withrow To: time-nuts Subject: [time-nuts] Looking for Datum TymServe 2000 (TS2000) manual Hello Time-Nuts, After a very long journey trying to figure out the correct cable configuration between the AcuTime GPS antenna (receiver) and a Datum TS2000 I now have it working. Now I am in need of a manual so I can talk over the serial port. The protocol is apparently not the same as the TS2100. I'm more than happy to share the cable schematic if anyone needs it. It would be the same for Bancomm bc627 and 635/7 (?) as well as the TS2000. If you have any of these units you could probably use many different Trimble receivers (Resolution-T for instance) with RS-422 converter (though I have not tried it - yet). Thanks in advance for any help. Skip Withrow == ___ 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] True Time Nut Mission: NASA's Deep Space Atomic Clock (DSAC)
Yeah -- delays happen. The DSAC is part of the US Air Force STP-2 program. STP-2 launch was awarded to SpaceX in December, 2012. But the Falcon Heavy only completed it's first launch earlier this week, and instead of sending a customer payload they send a Tesla to past the orbit of Mars. Correcting my earlier post, the new launch date for STP-2 appears to be "no earlier than" June, 2018. I'm relying on this source for launch estimates: https://spaceflightnow.com/launch-schedule/ -- Bill Byrom N5BB On Fri, Feb 9, 2018, at 7:54 AM, jimlux wrote: > On 2/8/18 8:55 PM, Bill Byrom wrote: > > After the successful Falcon Heavy launch earlier this week, it appears that > > the Deep Space Atomic Clock (DSAC) is now scheduled to go up in June 2018 > > on a Falcon Heavy carrying the US Air Force STP-2 test payloads. > > https://www.nasa.gov/feature/goddard/2018/nasa-tests-atomic-clock-for-deep-space-navigation > > > > For a fun video about this project suitable for non-time-nuts, see: > > https://www.nasa.gov/mission_pages/tdm/clock/sammy-the-second.html > > > > "The Deep Space Atomic Clock is being readied for flight next year. > Moving hardware from the laboratory to space meant conquering a number > of technological challenges." > > A number of really hard technological challenges. Aside from taking a > bench full of gear and squeezing it down to a few liters. > > Note the date on an earlier note: > "DSAC is scheduled for launch in mid-2016" > > > > > >> Date: Tue, 12 Jan 2016 17:31:26 -0600 > >> > >> Upcoming Event: Deep Space Atomic Clock > >> Jan. 14, 2016, at 7 p.m. PT (10 p.m. ET, 0300 UTC) > >> You can watch this event via USTREAM: http://www.ustream.tv/NASAJPL2 > >> > >> Speakers: > >> Todd Ely, DSAC Principal Investigator, JPL > >> Allen H. Farrington, DSAC Project Manager, JPL > >> http://www.nasa.gov/mission_pages/tdm/clock/clock_overview.html#.VpWMgK9OKK0 > >> Atomic clocks are an integral, yet almost invisible component of modern > >> life. > >> For space exploration, they have been the foundational frequency > >> standard for NASA's Deep Space Network. NASA's Deep Space Atomic Clock > >> (DSAC) Technology Demonstration Mission, led by the Jet Propulsion > >> Laboratory, has been maturing the latest Atomic Clock technologies into > >> a smaller package, suitable for installation on a variety of deep space > >> probes to enhance navigation precision and gravity science across the > >> solar system. > >> > >> DSAC is scheduled for launch in mid-2016. > >> Satellite being built by Surrey Satellite Technologies USA, Englewood, > >> CO > >> > >> > ___ > 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] True Time Nut Mission: NASA's Deep Space Atomic Clock (DSAC)
On 2/8/18 8:55 PM, Bill Byrom wrote: After the successful Falcon Heavy launch earlier this week, it appears that the Deep Space Atomic Clock (DSAC) is now scheduled to go up in June 2018 on a Falcon Heavy carrying the US Air Force STP-2 test payloads. https://www.nasa.gov/feature/goddard/2018/nasa-tests-atomic-clock-for-deep-space-navigation For a fun video about this project suitable for non-time-nuts, see: https://www.nasa.gov/mission_pages/tdm/clock/sammy-the-second.html "The Deep Space Atomic Clock is being readied for flight next year. Moving hardware from the laboratory to space meant conquering a number of technological challenges." A number of really hard technological challenges. Aside from taking a bench full of gear and squeezing it down to a few liters. Note the date on an earlier note: "DSAC is scheduled for launch in mid-2016" Date: Tue, 12 Jan 2016 17:31:26 -0600 Upcoming Event: Deep Space Atomic Clock Jan. 14, 2016, at 7 p.m. PT (10 p.m. ET, 0300 UTC) You can watch this event via USTREAM: http://www.ustream.tv/NASAJPL2 Speakers: Todd Ely, DSAC Principal Investigator, JPL Allen H. Farrington, DSAC Project Manager, JPL http://www.nasa.gov/mission_pages/tdm/clock/clock_overview.html#.VpWMgK9OKK0 Atomic clocks are an integral, yet almost invisible component of modern life. For space exploration, they have been the foundational frequency standard for NASA's Deep Space Network. NASA's Deep Space Atomic Clock (DSAC) Technology Demonstration Mission, led by the Jet Propulsion Laboratory, has been maturing the latest Atomic Clock technologies into a smaller package, suitable for installation on a variety of deep space probes to enhance navigation precision and gravity science across the solar system. DSAC is scheduled for launch in mid-2016. Satellite being built by Surrey Satellite Technologies USA, Englewood, CO ___ 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.
