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BASIC Radio Question
On Mon, 15 Dec 2003 07:05:02 GMT, (Steven
Shelikoff) wrote: On Mon, 15 Dec 2003 05:06:35 GMT, (Bob) wrote: On Sun, 14 Dec 2003 17:31:13 GMT, (Steven Shelikoff) wrote: On Sun, 14 Dec 2003 11:29:19 -0500, Jean Dufour wrote: VHF waves work "line of sight". They may be slightly curved around the horizon but they won't be much. So, whatever the power of the transmiter is, they won't reach more than 25 miles before getting lost in space. Well, not really. It all depends on antenna height. From the Jersey shore, not only can I talk to the Cape May CG station, but also to Baltimore and Chincoteague, Virginia. I have fairly reliable communications with CG stations up to over 100 miles. ducting...dangerous to rely on for reliable communications... It must be a pretty reliable duct because I hear the Baltimore CG station almost all the time from the Jersey Shore. It's faint of course, but perfectly readable. there are 2 considerations here. 1 is that hearing is not necessarily communications. that you can hear them doesn't mean you can reliably communicate the 2nd is that the ducting responsible for this can disappear, literally, in a second. --------------------------- to see who "wf3h" is, go to "qrz.com" and enter 'wf3h' in the field check my blog at: http://www.bobview.blogspot.com/ |
BASIC Radio Question
On Mon, 15 Dec 2003 07:05:02 GMT, (Steven
Shelikoff) wrote: On Mon, 15 Dec 2003 05:06:35 GMT, (Bob) wrote: On Sun, 14 Dec 2003 17:31:13 GMT, (Steven Shelikoff) wrote: On Sun, 14 Dec 2003 11:29:19 -0500, Jean Dufour wrote: VHF waves work "line of sight". They may be slightly curved around the horizon but they won't be much. So, whatever the power of the transmiter is, they won't reach more than 25 miles before getting lost in space. Well, not really. It all depends on antenna height. From the Jersey shore, not only can I talk to the Cape May CG station, but also to Baltimore and Chincoteague, Virginia. I have fairly reliable communications with CG stations up to over 100 miles. ducting...dangerous to rely on for reliable communications... It must be a pretty reliable duct because I hear the Baltimore CG station almost all the time from the Jersey Shore. It's faint of course, but perfectly readable. there are 2 considerations here. 1 is that hearing is not necessarily communications. that you can hear them doesn't mean you can reliably communicate the 2nd is that the ducting responsible for this can disappear, literally, in a second. --------------------------- to see who "wf3h" is, go to "qrz.com" and enter 'wf3h' in the field check my blog at: http://www.bobview.blogspot.com/ |
BASIC Radio Question
On Mon, 15 Dec 2003 08:56:49 -0500, "Jeff Morris"
wrote: Group Boston has their primary on the Hancock tower in Boston, plus repeaters in Plum Island north, and Marshfield south. Baltimore has a repeater at the C&D Canal (as well as south); and Chincoteague has one in Ocean City and one to the south. Both are within about 60 miles of the Jersey coast. These are all on high towers, and broadcast at much higher than 25 watts. If there is any ducting to be had, these signals will find it. In Boston I often hear Portland and Woods Hole, where the repeaters are 50+ miles away. Sometimes I get Bar Harbor. generally coast guard repeaters are not for public access. they are for public safety and CG use only. repeaters operate in 'duplex' mode (cf channels 20 and 24). for example, there are no CG repeaters accessible to the public in the NY city/n. NJ area. it's certainly possible to hear, from hundreds of miles away, CG stations that have 'high site' antennas (that's what they're called). but these are not repeaters. --------------------------- to see who "wf3h" is, go to "qrz.com" and enter 'wf3h' in the field check my blog at: http://www.bobview.blogspot.com/ |
BASIC Radio Question
On Mon, 15 Dec 2003 08:56:49 -0500, "Jeff Morris"
wrote: Group Boston has their primary on the Hancock tower in Boston, plus repeaters in Plum Island north, and Marshfield south. Baltimore has a repeater at the C&D Canal (as well as south); and Chincoteague has one in Ocean City and one to the south. Both are within about 60 miles of the Jersey coast. These are all on high towers, and broadcast at much higher than 25 watts. If there is any ducting to be had, these signals will find it. In Boston I often hear Portland and Woods Hole, where the repeaters are 50+ miles away. Sometimes I get Bar Harbor. generally coast guard repeaters are not for public access. they are for public safety and CG use only. repeaters operate in 'duplex' mode (cf channels 20 and 24). for example, there are no CG repeaters accessible to the public in the NY city/n. NJ area. it's certainly possible to hear, from hundreds of miles away, CG stations that have 'high site' antennas (that's what they're called). but these are not repeaters. --------------------------- to see who "wf3h" is, go to "qrz.com" and enter 'wf3h' in the field check my blog at: http://www.bobview.blogspot.com/ |
BASIC Radio Question
On Mon, 15 Dec 2003 16:53:00 GMT, Gary Schafer
wrote: The proper term is "remote base station". A Coast guard station may have several radio stations that they operate from one point. Those remote stations are tied to the operation point by phone line. Your signal does not get "repeated" over their system. that's correct. there are also 'high site' locations where an antenna is located on a high hill or tower, as opposed to the station's own tower and antenna. it's used as a last resort since it can be heard for quite a distance. the CG does have a repeater system (as does the auxiliary), but these are not for public use. They may transmit on more than one of those remote stations at the same time. They also listen to all of them at the same time. A repeater requires two frequencies ot operate. One to receive and one to transmit on. Channel 16 is only a single frequency. yep. also correct. --------------------------- to see who "wf3h" is, go to "qrz.com" and enter 'wf3h' in the field check my blog at: http://www.bobview.blogspot.com/ |
BASIC Radio Question
On Mon, 15 Dec 2003 16:53:00 GMT, Gary Schafer
wrote: The proper term is "remote base station". A Coast guard station may have several radio stations that they operate from one point. Those remote stations are tied to the operation point by phone line. Your signal does not get "repeated" over their system. that's correct. there are also 'high site' locations where an antenna is located on a high hill or tower, as opposed to the station's own tower and antenna. it's used as a last resort since it can be heard for quite a distance. the CG does have a repeater system (as does the auxiliary), but these are not for public use. They may transmit on more than one of those remote stations at the same time. They also listen to all of them at the same time. A repeater requires two frequencies ot operate. One to receive and one to transmit on. Channel 16 is only a single frequency. yep. also correct. --------------------------- to see who "wf3h" is, go to "qrz.com" and enter 'wf3h' in the field check my blog at: http://www.bobview.blogspot.com/ |
BASIC Radio Question
On Tue, 16 Dec 2003 02:45:14 GMT, (Bob) wrote:
On Mon, 15 Dec 2003 07:05:02 GMT, (Steven Shelikoff) wrote: On Mon, 15 Dec 2003 05:06:35 GMT, (Bob) wrote: On Sun, 14 Dec 2003 17:31:13 GMT, (Steven Shelikoff) wrote: On Sun, 14 Dec 2003 11:29:19 -0500, Jean Dufour wrote: VHF waves work "line of sight". They may be slightly curved around the horizon but they won't be much. So, whatever the power of the transmiter is, they won't reach more than 25 miles before getting lost in space. Well, not really. It all depends on antenna height. From the Jersey shore, not only can I talk to the Cape May CG station, but also to Baltimore and Chincoteague, Virginia. I have fairly reliable communications with CG stations up to over 100 miles. ducting...dangerous to rely on for reliable communications... It must be a pretty reliable duct because I hear the Baltimore CG station almost all the time from the Jersey Shore. It's faint of course, but perfectly readable. there are 2 considerations here. 1 is that hearing is not necessarily communications. that you can hear them doesn't mean you can reliably communicate I hear them almost all the time. The only times I've talked to the baltimore station, they heard me. the 2nd is that the ducting responsible for this can disappear, literally, in a second. I talked to the baltimore station a couple of times over the course of a few hours. They heard me. The point is that VHF signals *always* can go further than the calculated straight line of sight horizon, and frequently can go much further. Steve |
BASIC Radio Question
On Tue, 16 Dec 2003 02:45:14 GMT, (Bob) wrote:
On Mon, 15 Dec 2003 07:05:02 GMT, (Steven Shelikoff) wrote: On Mon, 15 Dec 2003 05:06:35 GMT, (Bob) wrote: On Sun, 14 Dec 2003 17:31:13 GMT, (Steven Shelikoff) wrote: On Sun, 14 Dec 2003 11:29:19 -0500, Jean Dufour wrote: VHF waves work "line of sight". They may be slightly curved around the horizon but they won't be much. So, whatever the power of the transmiter is, they won't reach more than 25 miles before getting lost in space. Well, not really. It all depends on antenna height. From the Jersey shore, not only can I talk to the Cape May CG station, but also to Baltimore and Chincoteague, Virginia. I have fairly reliable communications with CG stations up to over 100 miles. ducting...dangerous to rely on for reliable communications... It must be a pretty reliable duct because I hear the Baltimore CG station almost all the time from the Jersey Shore. It's faint of course, but perfectly readable. there are 2 considerations here. 1 is that hearing is not necessarily communications. that you can hear them doesn't mean you can reliably communicate I hear them almost all the time. The only times I've talked to the baltimore station, they heard me. the 2nd is that the ducting responsible for this can disappear, literally, in a second. I talked to the baltimore station a couple of times over the course of a few hours. They heard me. The point is that VHF signals *always* can go further than the calculated straight line of sight horizon, and frequently can go much further. Steve |
BASIC Radio Question
I can hit quite a few repeaters some of them 20+ miles
away on 2m just using a handheld with a rubber duckie antenna. Clearly line-of-sight is not quite the case. Repeater antennas are generally mounted high on towers or buildings but my antenna is only 6' or so. Doug, k3qt s/v Callista "Steven Shelikoff" wrote in message ... On Tue, 16 Dec 2003 02:45:14 GMT, (Bob) wrote: On Mon, 15 Dec 2003 07:05:02 GMT, (Steven Shelikoff) wrote: On Mon, 15 Dec 2003 05:06:35 GMT, (Bob) wrote: On Sun, 14 Dec 2003 17:31:13 GMT, (Steven Shelikoff) wrote: On Sun, 14 Dec 2003 11:29:19 -0500, Jean Dufour wrote: VHF waves work "line of sight". They may be slightly curved around the horizon but they won't be much. So, whatever the power of the transmiter is, they won't reach more than 25 miles before getting lost in space. Well, not really. It all depends on antenna height. From the Jersey shore, not only can I talk to the Cape May CG station, but also to Baltimore and Chincoteague, Virginia. I have fairly reliable communications with CG stations up to over 100 miles. ducting...dangerous to rely on for reliable communications... It must be a pretty reliable duct because I hear the Baltimore CG station almost all the time from the Jersey Shore. It's faint of course, but perfectly readable. there are 2 considerations here. 1 is that hearing is not necessarily communications. that you can hear them doesn't mean you can reliably communicate I hear them almost all the time. The only times I've talked to the baltimore station, they heard me. the 2nd is that the ducting responsible for this can disappear, literally, in a second. I talked to the baltimore station a couple of times over the course of a few hours. They heard me. The point is that VHF signals *always* can go further than the calculated straight line of sight horizon, and frequently can go much further. Steve |
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