Re: [time-nuts] LORAN broadcasts
Wildwood, New Jersey/ Near Cape May On 2/8/2020 2:21 PM, Jeffrey Pawlan wrote: I still have my Austrom LORAN receiver and the square loop antenna. It always seemed to have better stability than GPS so I was sad when they shut it off. Where is Wildwood and also does anyone know if there will ever be a station in the West Coast? I previously used Fallon NV. I am in San Jose, CA Regards, Jeffrey Pawlan WA6KBL ___ 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] DHS Resilient PNT Conformance Framework
Read the document, send it up the food chain for an HVA. Question: is is there a citable example / test case that a GPS can a) be rendered inoperable (bricked) by an external signal? b) not recoverable upon power cycling or other end-user accessible process? Martin On Dec 17, 2020, at 12:52 PM, Magnus Danielson wrote: Fellow time-nuts, DHS just published the work on Resilient PNT Conformance Framework, that has been in the works since last year. This is intended to be the framework for which multiple sectors align their standards, and a wide range of interest was involved. Hope it can be interesting reading for you. https://www.dhs.gov/publication/st-resilient-pnt-conformance-framework Cheers, Magnus 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.
[time-nuts] Re: 2nd Run of TimeHats
Sign me up for two, and how do we get you the money? Martin On 4/26/2021 8:32 AM, John Miller via time-nuts wrote: Hello everyone, I’ve seen a number of messages lately that reference the TimeHat boards I put together a couple of months ago, with lots of positive feedback, which I really appreciate. The first run of boards I did sold fairly quickly, and based on a number of emails I have gotten lately there seems to be some renewed interest. As such, I’m going to order up another batch of PCBs and parts, but I’d like to get an idea of how many I need to order to satisfy current demand. The GPS modules come from China, so there is about a two or three week wait them, so I want to make sure I have enough. For those not familiar, you can learn more about the TimeHat here: https://millerjs.org/timehat Regards, John ___ time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-le...@lists.febo.com To unsubscribe, go to and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-le...@lists.febo.com To unsubscribe, go to and follow the instructions there.
[time-nuts] Connector help?
Planning deployment of an HP 58516A GPS 1x4 antenna splitter with the external power option (option 05Q) at our makerspace. Anyone know what the mating DC connector is? martin ___ 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] Connector help?
Hi Bob, Antenna is a PCTEL GPS-TMG-HR-26NCM ( 26 dB gain) antenna that feeds a Polyphaser 095-0927T-A protector using 1/2 Super-flex. The HP 095-0927T-A would be downstream of the protector with about 100 feet of additional super-flex. Martin On 1/27/2019 5:17 PM, Bob kb8tq wrote: Hi Yes I know, this is beating a dead horse ….. Since the HP splitter will knock out everything that is not right on top of GPS, are you sure you want to go that route? Yes it does depend a bit on the antenna. If it’s one of the telecom / narrowband gizmos then the splitter will not have much affect. I tend fo find that in a lab setting as broadband a feed as possible is a really good idea. You never really know what will pop up on the bench next. Bob On Jan 27, 2019, at 4:17 PM, Martin Flynn wrote: Planning deployment of an 095-0927T-A GPS 1x4 antenna splitter with the external power option (option 05Q) at our makerspace. Anyone know what the mating DC connector is? martin ___ 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] DC distribution
Wire Ferrules are the best way to use thin wire in a powerpole http://www.ferrulesdirect.com/electrical/NonInsFerr2620.htm On 10/4/2019 5:07 PM, John Ackermann N8UR wrote: The idea of using a short piece of thicker wire is a good one. Thanks for that! On 10/4/19 3:17 PM, MLewis wrote: With audio signals, a soldered crimp is one of the worst possible connections. I wouldn't think it would be different for anything else, but may go undetected until failure. If you've used the correct size of crimp and used a proper crimping tool, then you've got the proper pressure for a solid reliable connection. If you then solder, the heat expands the crimp lessening the crimp pressure, and when it cools it's no longer at the correct crimp pressure (often the wire will pull right out), and with iffy wicking of solder. The worst of both methods combined in one. Where the wire is too thin for the crimp I have available, I've cut a piece of a correct thickness wire/cable, inserted that into the crimp along with the signal wire/cable, so it's crimped between them. I don't know if that is the best way of handling that, but it's worked for me. On 04/10/2019 11:41 AM, John Ackermann. N8UR wrote: West Mountain is a good source for all things PowerPole, but there are a bunch of other vendors as well. And do youself a favor -- spend $30 on the three size 15/30/45 amp crimping tool. It saves much aggravation. But if you're using thin wire, soldering after crimping is a good precaution. ___ 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. ___ 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] DC distribution
After a failure under load of a starter cable on a large generator, I finally broke down and bought a Burndy hydraulic crimper for the grounds and cables I normally use. Did two test low-tech tests: First test on a 1" section of 2/0 DLO cable, with a two bolt telco lug at each end. It failed at ~2200 ft/lbs, the wire itself broke strand by strand. Second test involved sawing the crimp across the barrel and looking for voids. Using factory lugs and die, no voids were visible at 25X magnification On 10/6/2019 2:46 PM, Mark Goldberg wrote: It is even more difficult. I bought some cables from a company because I did not have a crimper for 4/0. I was not impressed. My crimps were much better. I don't have a specific recommendation, but you should get a feel from them that they understand the standards. Places that do work for aviation generally have to do good work, as lives depend on it. Unfortunately, it is a high labor activity, so many are not in the US. A long time ago, I worked with some just south of the border in Mexico that did good work. Regards, Mark W7MLG ___ 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] can of worms: time-of-day in a community radio station
Our makerspace is using a BSD licensed product called OAS (On Air Screen) in the studio, with a slave displays planned at the engineers workstation, and in the Makerspace workshop . Link: github.com/saschaludwig/OnAirScreen OAS has been set up on an Raspberry PI, with the PoE shield on the back of the monitor. OAS loads itself full-screen, no keyboard or mouse needed. We are working on a supportable means to turn the various "lights" on the display(s) on and off automatically over the network using UDP messages. As an example: Our Wheatstone R60 console has a relay that activates when any of mixer channels are active and feeding the main output. The relay contacts will drive a logic (GPIO) pin on a single-board computer (Xunlong Orange Pi Zero). The Pi Zero is running a python application that will generate a UDP message on the network to activate the "on-air" light on each display. Obligatory Time nuts statement: Time standard is a Symmetricom XLi GPS Disciplined TCXO with the 10MHz option 73 Martin On 10/18/2019 4:33 PM, Bob kb8tq wrote: Hi A very normal internet based NTP setup will do what you wish to do. The main task is to make sure that your devices are *really* running NTP and not some odd thing built into their OS. The more devices / operating systems / OS versions / system configurations you have the more exciting this gets. Bob On Oct 18, 2019, at 3:20 PM, Eric Scace wrote: I fear that I am developing a reputation for bringing to the list rather oddball questions. In my rôle as agent provocateur, therefore, here is another such problem. Questions for you are at the end. Thanks for your thoughts,. — Eric Issue: A community broadcast radio station with multiple studio locations wishes to improve the display of time-of-day throughout the station’s operating environments. Its current legacy approaches (described below) cause problems such as: on-air presenters fail to smoothly segue into scheduled program feeds (e.g., BBC news) because the studio clock is “a little off”… and because the studio clock is digital. [Quick: how many more seconds can you speak before the top of the hour when a digital clock shows 4:59:42? Watching an analog stepping second hand is much easier in this situation.] computers that automatically capture audio programs to files in storage sometimes truncate the start or end of the program because the computer’s idea of time-of-day disagrees with that of the program source. desktop computers throughout the station, including in production studios, all render slightly different versions of time-of-day to their users. servers (e.g, for streaming, for archiving shows) are similarly in cheerful disagreement as to time of day. wall clocks studios in one city show a different time to their engineers than the studios in another city, rendering handoffs more complicated. Ditto for remote broadcast sites, and even between studios in the same site. requires manual intervention to bring the most egregious systems back to some semblance of reality Background & existing situation: Commercial broadcast stations have more money and technology to solve these problems. In contrast, “community radio” stations have limited funds and are largely staffed by volunteers (like me!). In this case, the existing systems are a hodgepodge: mostly Windows OS PCs, with a couple of Macs Linux servers mash-mash of wall clocks, the best of which is a LaCrosse WWVB digital in the primary on-air studio. The WWVB signal is more than adequate but the LaCross display format is sub-optimal for studio use. Goals: (first pass) minimum accuracy requirement: time-of-day displayed within ±0.1 second of UTC timescale. (Two clocks both falling outside this range will cause program handoffs to be uncomfortably tight or loose.) no manual intervention required for summer/winter time transitions no manual intervention required for leap seconds leap second: no smearing (minimum requirement) accurate leap second display (desirable but unlikely to be achievable) desirable consistency goal: time-of-day displayed within ±0.025 second throughout each site. At this level, two adjacent clock displays will not be perceived as out of step by a person. presentation goals: studio/remote broadcast control point time-of-day displayed in both analog (with stepped seconds hands) and digital form (preferred H:MM). If digital form includes seconds, the seconds digits should be visually separated; e.g..smaller. A presenter can then, at a glance and without confusion, announce the time (“four twenty-three”) from the digital display. Date in form “Oct 17 Thu” available. medium-term desirable: displays continue within specs for accuracy/consistency across power cutovers (to/from generator) and public Internet outages. maintenance goals: "eschew emergencies”: no one should have to rush to the station in the middle of the night, nor drop what their doing during the
[time-nuts] Re: About 10 MHz Optical Distro
Started into white rabbit on fiber recently - one tidbit that was shared with me: White rabbit typically uses a BIDI over a single fiber to keep the fiber length (and respective transmit / receive times) as close as possible Martin W2RWJ On 8/29/2021 10:03 AM, paul swed wrote: I did see the tp link. Pretty amazing. For the group these devices are pretty useful. But watch out for the wavelength of the light you typically need matching fiber. Also note the connectors and get the matching units. I have no idea how well 1350 light would pass on multimode for 850 nm. Regards Paul WB8TSL On Sat, Aug 28, 2021 at 11:57 PM Lux, Jim wrote: On 8/28/21 7:13 PM, AC0XU (Jim) wrote: Thanks to all the posters. Especially to Dana - That is exactly what I was looking for - suggestions for parts and/or circuits to do the job. I was originally thinking that I would go with a digital circuit (sine to square to sine), but maybe analog/sinewave would be simpler and perform about as well. Anyway, I have ordered some of the recommended optical transceivers. We'll see how that works out. One or two posters mentioned that phase noise and/or thermal stability may be issues. The referenced research papers don't seem to indicate that phase noise is a problem. I don't think that thermal effects will be a big problem for me - I just need to check the phase calibration from time to time. Certainly there are expensive commerical optical clock distribution systems with excellent properties. Maybe the devil is in the details... My specifical application at the moment is putting several SDRs at diverse antenna locs and feeding the IF via ethernet-converted-to-optical to my computer. I may want to transmit at some point but receiving is all I want to do for now. Still need a way to get a stable ref clock to each radio to provide phase coherence I only need 50-60 meters but an optical solution with single mode fibers can go many km if I ever wanted to scale up. Anyway, my plan is to have only power carried by copper. I don't want to go with coax, twisted pair, or any other copper solution because of high ambient noise levels in my area and a desire to avoid adding to it. Stringing several 100 meters of copper about my yard, carrying 10 MHz clock signals, no matter if the cables are well shielded, doesn't seem like a great idea. This is totally the thing that OVRO LWA dealt with.. Not only is fiber a LOT cheaper than coax, it solves a lot of problems. Ethernet to fiber is really cheap ($20 for an endpoint from TP-link ) $20 from newegg https://www.newegg.com/tp-link-mc100cm/p/N82E16833704015?item=N82E16833704015 ___ time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-le...@lists.febo.com To unsubscribe, go to and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-le...@lists.febo.com To unsubscribe, go to and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-le...@lists.febo.com To unsubscribe, go to and follow the instructions there.
[time-nuts] Symmetricom XLi question
Picked up a Symmetricom XLi with two A/C supplies and two empty slots. Question #1 Is there a preference which of the two empty slots the GPS C/A Receiver (87-8028-2) is placed in? Question #2 Anyone have slot covers sitting around? Martin ___ time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-le...@lists.febo.com To unsubscribe, go to and follow the instructions there.
[time-nuts] Lucent 849143995
Hi Folks, Would like to donate an external GPS antenna for the TS2100 at the local radio astronomy site. Anyone know what voltage the Lucent 849143995 GPS antenna is and if it's suitable for the TS2100? Martin A Flynn / W2RWJ Computer Deconstruction Laboratory 2201 Marconi Road Wall Township, NJ 07719 Tel: +01 732-456-5001 Email: martin.fl...@compdecon.org Online: www.compdecon.org Facebook: https://www.facebook.com/compdecon/ ___ time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-le...@lists.febo.com To unsubscribe, go to and follow the instructions there.
[time-nuts] Dimensioned Drawing LUCENT-SYMMETRICOM Z3810AS KS24361
Since my homemade version did not turn out as well as I had hoped, I was planning to have my local fab shop laser cut a rack panel for our "new" LUCENT-SYMMETRICOM Z3810AS (KS24361) Before break out the ruler, anyone have a dimensioned drawing of the mounting and panel holes? Martin A Flynn / W2RWJ Computer Deconstruction Laboratory 2201 Marconi Road Wall Township, NJ 07719 Tel: +01 732-456-5001 Email: martin.fl...@compdecon.org Online: www.compdecon.org Facebook: https://www.facebook.com/compdecon/ ___ time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-le...@lists.febo.com To unsubscribe, go to and follow the instructions there.
