Re: [time-nuts] Toy radiolocation and LORAN envelope
Hello Andrea, The angle could be found with a directional antenna or inerferometry, but about the distance? About the only reliable way to locate hidden transmitters is by field strength. The problem in built-up areas is reflections. At one time Doppler DF systems were popular, but anybody who has used one will tell you they are usually more trouble than they are worth. A simple beam or dipole is useful, but only when out in the open country By simply gridding the area, and drawing a field strength map, you will soon cut the location down to a small area. Then with a field strength meter you can walk right up to it. When doing professional DF work, I would use a scanner with an external S-meter and an effective attenuator in the antenna lead. Regards... Zim ___ 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] Wenzel oscillator - L1 value?
Most crystals are cut to be terminated with a certain capacitance. If you adjust this capacitance you can vary the frequency slightly. However if you terminate the crystal with a series tuned circuit (LC) you can vary the reactance over a much wider range, and consequently get a wider frequency swing. You simply put an inductor in series with the crystal, with a value which resonates with the terminating capacitor at the crystal frequency. When the tuned circuit is adjusted slightly ether side of resonance, the crystal sees either capacitive or inductive reactance. You can adjust either the inductor or the capacitor. With too much variation however, the crystal looses control and the circuit becomes free running and unstable. For back-ground info read up on Tunable Crystal Oscillators and Voltage Controlled Crystal Oscillators Amateur Radio operators often need to pull the frequency of a crystal oscillator and have evolved lots of tricks. Look in some of the Amateur Handbooks. One trick is to put two identical crystals in parallel. They behave as double-humped over-coupled circuits and can be pulled much further than a single crystal. regards Zim ___ 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] Power Supply for AD9852 / AD9854
I would assume that using two voltage regulators will spread the load. For the AD9851 I'am planning to put external radiator glued on top of it. One of my commercial projects used eight x AD9852. During development they definitely needed small heat sinks glued on top of each chip. I discovered that it's quite easy to cook a chip. In the final version it was possible to switch off many of the internal blocks so that the heat sinks were no longer necessary. .. Zim ___ 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] Power Supply for AD9852 / AD9854
My versions of a DDS using two AD9910 in Quadrature http://members.wideband.net.au/gzimmer/QuadDDS/default.html regards ... Zm ___ 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] Power Supply for AD9852 / AD9854
Unless it’s already on a board, this is not a simple chip to use in a home environment. Nevertheless, some of us do manage. But it's true, the AD9852/AD9854 does run very hot. It's worth mentioning that the AD9910/AD9912 family runs much cooler. Mine aren't even warm to the touch. This of course is due to the power hungry parts of the chip running on 1.8V instead of 3.3V . Zim ___ 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] A small piece on HP's hydrogen maser in 1968
http://www.hp.com/hpinfo/abouthp/histnfacts/publications/measure/pdf/1968_09.pdf This broken link business is very common in some browsers (in Windows). It's because there's an underline in the original URL. When the browser sees a link it underlines it in blue, which converts the underline into a Rich Text or HTML graphics character. The simple cure is to cut and paste the URL into a text file with notepad. This gets rid of the fancy format characters. An even better way is to switch off HTML and RTF if you can. Email was meant to be text. . Zim ___ 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] New WWVB modulation format receivers (NOT)
One of the simplest ways to receive VLF signals is to buy a surplus Selective Level Meter. They were an important piece of test equipment used by the analog line-line telephony people. Now of course, surplus to requirements. If you hunt around they can be found at very low prices. ... Zim ___ 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] New WWVB modulation format receivers
Several years ago I spotted a clever PIC-based software (DSP-ish) approach to WWVB modulation Perhaps it was mine? Years ago I designed a PSK31 decoder using a PIC. It worked very well for fixed frequencies, but I concluded that making it tunable was beyond the resources of the PICs then available. If I remember correctly, it used a simple delay line and multiplied the early and late version of the signal. Most of the overheads were in synchronisation and decoding the Varicode modulation. I imagine it would be fairly easy to get it working for WWVB. All it would take would be sufficient enthusiasm. Something I have a shortage of these days :-) .. Zim VK3GJZ ___ 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] New WWVB modulation format receivers (NOT)
I have a Kenwood TS-940S transceiver that can receive 60 kHz but I have never heard anything Where are you? It must be deaf as a post. I can hear WWVB in Australia ! (or at least I could till JJY-60 started in 2001) ... Zim ___ 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] How to open solder-sealed OCXOs?
What's the best way to open an OCXO in the typical solder-sealed tinned steel can? Use a high wattage iron to melt the solder at one point, prise the gap open with a flat screwdriver, then work along the join. Solder is soft. so once you get it started you should be able to roll it open like a can of tuna. You could use a dremmel and a cutting disk, but the vibration might kill the Xtal. Alternatively, a hot air gun might work if you are quick enough not to cook the innards. Zim ___ 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] Nortel GPSDO osc age alarm
9.8304 MHz output, an odd frequency used by the cell tower equipment 9.8304 MHz is 8 x 1.2288 MHz which is the CDMA PN chip rate a rather fundamental frequency to the CDMA phone system Zim ___ 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] Local Solar Time Clock
An electro-mechanical RX for VLF. http://www.wireless.org.uk/mechrx.htm enjoy ___ 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] Lady Heather and the NTGS50AA
Ignatio, Not exactly what you have asked, but I notice that Trimble Tboltmon won't connect to a device which requires Odd parity. You can select Odd parity, but it fails to connect, and the details at the bottom remain fixed at N,8,1 So for Odd parity I can only use Trimble Studio. I haven't figured out exactly why yet. regards Zim ___ 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] Trimble Resolution SMTx GPS Timing Receiver:
Hi folks, I have my little Trimble Resolution SMTx GPS module running. Details at: http://members.wideband.net.au/gzimmer/Time/default.html later ... Zim ___ 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] Trimble Studio, what is it?
Did you mean 2.01.6 or is there a newer version? Version 2.01.6 is the latest version I've seen. It's the first which drops the beta label. ... Zim ___ 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] Trimble Studio, what is it?
Folks, Nigel GM8PZR explained all this very thoroughly a few days ago... It seem there are more than one development thread of Thrimble Studio running. I've seen at least three versions. This link gives you version V1.23.0 11/20/2013 (status beta) http://www.mmnt.net/db/0/0/ftp.trimble.com/pub/sct/misc/bin/TrimbleStudio Which does seem to be the latest official version. If you have trouble connecting with Studio, try unplugging your Serial cable until after the PC has booted. It seems that WinXP confuses it with your mouse. regards . Zim ___ 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] Trimble Studio, what is it?
Hi Dave, That link to mmnt.net resulted in some strange russian gaming site Yes, somehow I posted the wrong link. It should have been: ftp://ftp.trimble.com/pub/sct/misc/bin/TrimbleStudio I don't see any difference in the V1.23.0.0 and the V2.01.6 Try the update function in Help. On mine it didn't work (must be hard wired to some other address) Zim, in the Receiver Version window, I have V3.68 12/16/2004 for my Nortel, what does yours say? Mine says 3.75 8/7/6 (2006 ?) (will try to attach pix) regards .. Zim attachment: Serial.JPG___ 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] WAAS.....
Hi Brian, Thanks for the fascinating story! For that matter, is anyone running one of the new multi-system receivers? I hope to play with Resolution SMT GG which is the Multi-GNSS version of the Desolution SMT. What I'm keen to find out is which of the standard GPS diagnostic software also handles the newer satelites (GLONASS, QZSS, SBAS, etc) or whether specialist software is needed. Anybody know? Thanks ... Zim ___ 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] Motorola GPS antenna type GCNT20A3A
On 12/12/2013 10:57 AM, Russ Ramirez wrote: FYI, in case anyone should be interested. $20 http://www.goldmine-elec-products.com/prodinfo.asp?number=G19738 Motorola GCNT20A3A +25db Antenna. For what it's worth, I purchased one of these and it eventually arrived after a rather round-about trip. I hooked it up just now and it does seem to work, but signals are definitely not as strong as my Nokia 470290a-101 +20db Antenna, however it is sited in a poorer location and with a longer piece of coax. So although they are an Engineering Sample, they do seem to work. Eventually I'm mount it higher up and give it a fairer test. later Zim ___ 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] Trimble Studio, what is it?
Hi Chris, I see occasional references to Trimble Studio here. What is it please? For a list of features, see: http://www.wavedigm.com/xe/studio That page also has a Users Guide and the application itself. regards Zim ___ 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] Trimble: Using RS-232 via with USB adapter
Hi folks, This has probably been covered before, but I thought it worth knowing I wanted to use my new laptop with my Trimble/Nortel GSP receiver. As my laptop doesn't have an RS-232 port, I purchased a cheap USB to RS-232 adaptor. After a few false starts I found that the older Tboltmon software runs quite happily via the adaptor. A pleasant surprise however was that the newer USB based TrimbleStudio also runs. The TrimbleStudio has a few nice additions over the older software. regards . Zim ___ 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] Trimble: Using RS-232 via with USB adapter
Sorry, that doesn't make much sense, does it... I just realised that TrimbleStudio is not just USB. It runs quiet happily with RS-232 . Zim ___ 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] Trimble Thunderbolt 1pps
Interesting discussion re getting the 1PPS into a PC to synchronise a timing program. I use WSPR for ham radio and was wondering how to do this. Can you tell me which (Windows) time synch programs can use the 1PPS on DCD of the RS232 interface please? Next step would be to build a variable delay so I can trim the 1 PPS timing for those stations which are a little off-time and can't be decoded. thanks Zim ___ 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] Trimble Thunderbolt 1pps
Can you tell me which (Windows) time synch programs can use the 1PPS on DCD of the RS232 interface please? To answer my own question: Here's one... http://www.visualgps.net/NMEATime/default.htm There are a few others listed at http://www.gpskit.nl/links-en.htm Zim ___ 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] Trimble Thunderbolt 1pps
Unless you bring the 1pps in and synchronize with that, you are probably better off just running NTP. Yes, that is the idea. I often don't have access to the Internet when running WSPR. eg when operating portable in remote areas or marine. Thanks . Zim ___ 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] sysclock source for AD9912 DDS?
Hi Anders, Have a look at my AD9910 quadrature DDS http://members.wideband.net.au/gzimmer/QuadDDS/default.html I used a Crystek 1GHz SAW oscillator regards Zim ___ 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] Trimble/Nortel 45000 GPS Locked Reference Oscillatorboard
Hi Dave, Thanks for your post. I'd like to see some of your LH traces if you don't mind... Do you mean with the Lady Heather software? I'll leave it running a while and collect some data. Yes, I did hesitate running it on AC, but it draws little current and does seem to be happy enough. I do have a switch mode supply to put in the box eventually. regards Zim . VK3GJZ ___ 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] Trimble/Nortel 45000 GPS Locked Reference Oscillator board
Hi Folks, I though you might be interested in a couple of my recent projects... I purchased a Trimble/Nortel 45000 GPS Locked Reference Oscillator board on ebay and used it to drive my Silicon Chip Magazine High Resolution Frequency Counter. Details at http://members.wideband.net.au/gzimmer/ More anon Zim VK3GJZ ___ 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.
