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#1
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How important are time and frequency references to amateur radio
operators? I've been working on a radio controlled clock design that would be capable of generating a 32.768 kHz, 60 kHz, 240 kHz, 1 MHz and 10 MHz frequency references in addition to providing the time and date. Initially it would be capable of receiving the 60 kHz transmissions of WWVB and MSF. With minor tweaks other stations could be received. Would this be useful to others? -- Rick |
#2
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In article , rickman
wrote: How important are time and frequency references to amateur radio operators? I've been working on a radio controlled clock design that would be capable of generating a 32.768 kHz, 60 kHz, 240 kHz, 1 MHz and 10 MHz frequency references in addition to providing the time and date. Initially it would be capable of receiving the 60 kHz transmissions of WWVB and MSF. With minor tweaks other stations could be received. Would this be useful to others? Rick- Anyone who would use your frequency reference might be interested if it is less expensive than other methods. I believe GPS-trained references are available. I have a rubidium-controlled oscillator I bought on E-Bay. For routine Ham Radio use, I depend on 20 MHz WWV to periodically check the calibration of my transceivers. By switching between CW and CW-R, I can adjust the equipment so the CW pitch is the same for both. I am confident that I can adjust a radio so it is within one Hz at 20 MHz. That puts me within 0.05 parts per million, at least at the moment I make the adjustment. I expect the equipment to drift over time and temperature. Most Amateur Radio Operators do not worry that much about frequency. Some of the people I talk to on higher frequencies, drift over a few minutes time. Nobody seems to care! Fred K4DII |
#3
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On 18/04/2016 15:39, rickman wrote:
How important are time and frequency references to amateur radio operators? I've been working on a radio controlled clock design that would be capable of generating a 32.768 kHz, 60 kHz, 240 kHz, 1 MHz and 10 MHz frequency references in addition to providing the time and date. Initially it would be capable of receiving the 60 kHz transmissions of WWVB and MSF. With minor tweaks other stations could be received. Would this be useful to others? A good frequency standard has many uses for the radio amateur. There are many designs around many using GPS as the reference source as well as MSF and the like. -- Peter Crosland Reply address is valid |
#4
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On 18/04/16 15:39, rickman wrote:
How important are time and frequency references to amateur radio operators? I've been working on a radio controlled clock design that would be capable of generating a 32.768 kHz, 60 kHz, 240 kHz, 1 MHz and 10 MHz frequency references in addition to providing the time and date. Initially it would be capable of receiving the 60 kHz transmissions of WWVB and MSF. With minor tweaks other stations could be received. Would this be useful to others? Anyone who wants high accuracy off air time and frequency standards would use GPS these days. Even that is almost two decade old technology in amateur radio usage: http://www.tapr.org/kits_tac2.html Also note that cross-posting to a moderated newsgroup will delay the posting in the unmoderated group and cross-posting to two moderated groups will, almost certainly, stop it being distributed at all. |
#5
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#6
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On 4/18/2016 5:43 PM, David Woolley wrote:
On 18/04/16 15:39, rickman wrote: How important are time and frequency references to amateur radio operators? I've been working on a radio controlled clock design that would be capable of generating a 32.768 kHz, 60 kHz, 240 kHz, 1 MHz and 10 MHz frequency references in addition to providing the time and date. Initially it would be capable of receiving the 60 kHz transmissions of WWVB and MSF. With minor tweaks other stations could be received. Would this be useful to others? Anyone who wants high accuracy off air time and frequency standards would use GPS these days. Even that is almost two decade old technology in amateur radio usage: http://www.tapr.org/kits_tac2.html Is there something about GPS that is inherently superior for a frequency reference? For setting a time, GPS can provide a smaller offset, but I don't see where it has any advantages over WWVB or similar station broadcasts where you can receive them. The main limitation of a GPS receiver is the need for an outside antenna for many installations. A WWVB receiver is self contained and much lower cost. -- Rick |
#7
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In article rickman writes:
On 4/18/2016 5:43 PM, David Woolley wrote: On 18/04/16 15:39, rickman wrote: How important are time and frequency references to amateur radio operators? I've been working on a radio controlled clock design that would be capable of generating a 32.768 kHz, 60 kHz, 240 kHz, 1 MHz and 10 MHz frequency references in addition to providing the time and date. Initially it would be capable of receiving the 60 kHz transmissions of WWVB and MSF. With minor tweaks other stations could be received. Would this be useful to others? Anyone who wants high accuracy off air time and frequency standards would use GPS these days. Even that is almost two decade old technology in amateur radio usage: http://www.tapr.org/kits_tac2.html Is there something about GPS that is inherently superior for a frequency reference? For setting a time, GPS can provide a smaller offset, but I don't see where it has any advantages over WWVB or similar station broadcasts where you can receive them. The main limitation of a GPS receiver is the need for an outside antenna for many installations. A WWVB receiver is self contained and much lower cost. GPS allows accurate locking to frequency, WWVB no longer does, since they use phase modulation on the WWVB signal. The "low cost" WWVB receivers never could do that, they are only able to be used for clock setting, not accurate frequency determination. The WWVB signals are much more affected by the ionosphere, as daytime absorbtion can make the signal unusable to small receve antennas. Also, WWVB does need an antenna for good performance, especially compared to small indoor antennas. WWVB suffers from occasional interference on the east coast from MSF. Alan |
#8
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rickman wrote:
On 4/18/2016 5:43 PM, David Woolley wrote: On 18/04/16 15:39, rickman wrote: How important are time and frequency references to amateur radio operators? I've been working on a radio controlled clock design that would be capable of generating a 32.768 kHz, 60 kHz, 240 kHz, 1 MHz and 10 MHz frequency references in addition to providing the time and date. Initially it would be capable of receiving the 60 kHz transmissions of WWVB and MSF. With minor tweaks other stations could be received. Would this be useful to others? Anyone who wants high accuracy off air time and frequency standards would use GPS these days. Even that is almost two decade old technology in amateur radio usage: http://www.tapr.org/kits_tac2.html Is there something about GPS that is inherently superior for a frequency reference? For setting a time, GPS can provide a smaller offset, but I don't see where it has any advantages over WWVB or similar station broadcasts where you can receive them. The direct-sight UHF radio link provides less jitter and uncertainty than the VLF signal that suffers from propagation effects. The main limitation of a GPS receiver is the need for an outside antenna for many installations. A WWVB receiver is self contained and much lower cost. Sure it can be easier to place an antenna for a VLF station, but on the other hand there is much more interference, mainly from switchmode powersupplies these days (in the old days it was from CRT computer monitors), but also from lightning. |
#10
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On 4/20/2016 12:01 PM, Rob wrote:
rickman wrote: On 4/18/2016 5:43 PM, David Woolley wrote: On 18/04/16 15:39, rickman wrote: How important are time and frequency references to amateur radio operators? I've been working on a radio controlled clock design that would be capable of generating a 32.768 kHz, 60 kHz, 240 kHz, 1 MHz and 10 MHz frequency references in addition to providing the time and date. Initially it would be capable of receiving the 60 kHz transmissions of WWVB and MSF. With minor tweaks other stations could be received. Would this be useful to others? Anyone who wants high accuracy off air time and frequency standards would use GPS these days. Even that is almost two decade old technology in amateur radio usage: http://www.tapr.org/kits_tac2.html Is there something about GPS that is inherently superior for a frequency reference? For setting a time, GPS can provide a smaller offset, but I don't see where it has any advantages over WWVB or similar station broadcasts where you can receive them. The direct-sight UHF radio link provides less jitter and uncertainty than the VLF signal that suffers from propagation effects. That is important if you are looking for microsecond timing. But it has very little impact on use as a frequency reference. The main limitation of a GPS receiver is the need for an outside antenna for many installations. A WWVB receiver is self contained and much lower cost. Sure it can be easier to place an antenna for a VLF station, but on the other hand there is much more interference, mainly from switchmode powersupplies these days (in the old days it was from CRT computer monitors), but also from lightning. I guess you aren't familiar with the extremely narrow band timing signals, 1 bps. I'm working on a receiver with a 30 Hz bandwidth to exclude environmental noise. -- Rick |
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