why is it that i can only hear the trains (engineer's) on my scanner when they are within a half mile of me, but i can hear Dispatcher that is all the way in Boston? I live in North Attleboro pretty close to the tracks, and i can hear the trains talk when they are in my area. there is a radio tower in Attleboro where the Middleboro Sec. connects to the NEC. but i don't think the radio tower is in use anymore, the actual building isn't being used
Railroad Forums
Radio and Train distances
- Discussion related to railroad radio frequencies, railroad communication practices, equipment, and more.
Moderator: Aa3rt
Perhaps the dispacher's channel has a repeater, so the signal you are listening in on may be only a short distance away.
Most Railroads have a central dispatcher who is connected to a series of high powered towers placed along the tracks every 20 or 30 miles. Train radios are not as powerful as the dispatch transmitters and.... train antennas on the engines are obviously not nearly as high as the dispatch towers. But the dispatch antenna towers being high, can hear the train traffic quite well for some distance. That is why you can't hear the trains unless they are very close to you, because their antennas are too low. To hear the trains farther out, you will need to put up an antenna tuned to 160-161 mHz as high as possible to hear them. I have an antenna mounted about 40 feet up on my ham radio tower and can hear NS dispatch transmissions 50-75 miles up and down the line between Cincinnati and the Tennessee border. I can hear the trains themselves about 10-15 miles up or down the line. The dispatches on the NS in our area come out of Knoxville, TN or Atlanta, GA...both well beyond normal VHF distance, but by means of linked towers along the line, the dispatcher can communicate with the trains as the travel from one area to another. The CSX around here dispatches from Jacksonville, FL through a series of towers along their lines here in KY. Hope this helps.
:D :D :D
:D :D :D
Tom, KR4BD
Lexington, KY
Lexington, KY
yes, that did help, thanks for the info.....there is a radio tower in Attleboro, and i guess it is still in use then
kr4bd wrote:Most Railroads have a central dispatcher who is connected to a series of high powered towers placed along the tracks every 20 or 30 miles. ... The dispatches on the NS in our area come out of Knoxville, TN or Atlanta, GA...both well beyond normal VHF distance, but by means of linked towers along the line, the dispatcher can communicate with the trains as the travel from one area to another. The CSX around here dispatches from Jacksonville, FL through a series of towers along their lines here in KY.Just to expand on your info, the way that CSX and all other Class 1's that have a centeral dispatch work is that instead of the signal being repeated by VHF to the towers, they are connected through lease lines (or now, sometimes DSL) that are run through the Phone Company. It's a dedicated line that is always open, making a direct connection betwen the dispatch center and the broadcast towers along the subdivision. I've heard of them being able to turn on specific areas (towers or sets of towers) of the subdivision so they don't broadcast to the whole line (thus talking over local radio broadcasts or Defect Detectors). That's why you may hear them say that they don't have that channel, it's because they are off in some other area, and their system is only set up for the Road channel and maybe another sub channel. I have heard this before from the UP dispatcher in Spring, TX.
NK tower on the Lehigh Line in Newark, NJ was replaced by a remote link a couple of years ago. This is the portion used by NJ transit for Raritan Valley Line (ex CNJ) trains a mile or so west of the NEC Hunter Interlocking. A 60 or 70 foot or so radio antenna tower and an equipment shack were constructed and a lease line used for this remote base. Seems to work fine.
~Ken :: Fairmont ex-UP/MP C436 MT-14M1 ::
Black River Railroad Historical Trust :: [/url]
Black River Railroad Historical Trust :: [/url]
I have the same issue with G up here in Haverhill.
The dispatchers are transmitting from high locations, the trains are not.
The only thing you can do is to improve your antenna system and you will be able to hear the trains further away.
Recommend also that you have the delay setting for the railroad channels involved turned off. As soon as the dispatcher stops talking the train usually will respond on a different channel. If that is the case you want your scanner to go right over to the channel the trains talk on.
A scanner antenna outside and as high as possible will work a lot better than the antenna that comes with the scanner.
Fortunately or unfortunately, around here, if you want to hear reasonably well and aren't way up on a mountain you have to optimize your antenna system.
The dispatchers are transmitting from high locations, the trains are not.
The only thing you can do is to improve your antenna system and you will be able to hear the trains further away.
Recommend also that you have the delay setting for the railroad channels involved turned off. As soon as the dispatcher stops talking the train usually will respond on a different channel. If that is the case you want your scanner to go right over to the channel the trains talk on.
A scanner antenna outside and as high as possible will work a lot better than the antenna that comes with the scanner.
Fortunately or unfortunately, around here, if you want to hear reasonably well and aren't way up on a mountain you have to optimize your antenna system.
Un-like all the other railroads around here, Guilford does not use the same channel for two-way transmissions. The train crews talk on one, and the dispatcher talks on another. So to get the whole discussion, you will need both frequencies.
Dispatch will talk through a repeater, or series of them, usually at 40 to 100 watt output. Many trains will have portable radios which only push 4 watts, and even if they have the hard installed mobiles, they are 40 watt and as previously stated operating at ground level.
If you are near a repeater, you will hear that, but not always the reply.
As far as double frequency TX/RX, you have to have the frequency pairs to be able to hear both conversations. (this is because a series of repeaters will "flip-flop" the TX/RX along the line.) (you transmit on one freqency, listen on another)
In addition, most will have a PL code which means they are not operating on open (carrier) squelch. There are DPL and TPL codes. (digital and tone)
If you are near a repeater, you will hear that, but not always the reply.
As far as double frequency TX/RX, you have to have the frequency pairs to be able to hear both conversations. (this is because a series of repeaters will "flip-flop" the TX/RX along the line.) (you transmit on one freqency, listen on another)
In addition, most will have a PL code which means they are not operating on open (carrier) squelch. There are DPL and TPL codes. (digital and tone)
Bring back the Slumbercoaches!!
I am curious as to the arrangement for long distant trains, such as the Calif. Zephyr or the Empire Builder.
Do the long distance trains use telephone lease lines, as roee mentioned on the CSX? Are there repeaters all along the long distance routes? If regular transmiitter towers, are there towers at regular intervals along the route...or just at station stops?
With the Empire Builder, there is a lot of distance between the stops, especially through N. Dakota and northern Montana. I wonder about the power output of the transmitters..and what kind of reception distance one could expect.
Richard
Do the long distance trains use telephone lease lines, as roee mentioned on the CSX? Are there repeaters all along the long distance routes? If regular transmiitter towers, are there towers at regular intervals along the route...or just at station stops?
With the Empire Builder, there is a lot of distance between the stops, especially through N. Dakota and northern Montana. I wonder about the power output of the transmitters..and what kind of reception distance one could expect.
Richard
In 1998, my family and I traveled from Chicago to Portland on the Empire Builder. From Portland to Emeryville, CA, we took the Coastal Starlight and then it was the California Zephyr Eastward to return to Chicago. I am a "radio nut" (ham) and prior to the trip, I found all the frequencies for all the Roads involved on the internet and programmed them into my scanner. Amtrak uses the various "Road" frequencies of the lines it operates over as well as some of their own frequencies for use within the train itself. The frequencies used do change from district-to-district, but I had them all plugged into my scanner, so I don't think I missed much on the trip. There are communication towers all along the tracks which keep the train in constant contact with a dispatcher. I remember when we were on UP track in Nevada and Utah, the dispatcher was relayed out of Omaha to towers near our train. Going across Montana, the temperature was VERY HOT (it was July) and I even copied several "slow orders" as rails tend to buckle in hot weather!
As for power on the train radios: I believe most of the radios in the cabs are in the 40-50 watt range. Handheld radios generally are under 5 watts. My wife, kids and I are all hams and we communicated among ourselves throughout the train on the two meter ham band (146 mHz) with no problems using just 2 or 3 watts. I saw other folks on the train with scanners and the Amtrak people had no problem with us using our radios.
The range of a 50 watt VHF radio to a 200' tower can be 40-50 miles over flat terrain. In mountainous areas, towers are located closer together and/or on higher ground (mountain tops) to increase the effective range. By using directional yagi (multi-element, high gain) antennas on the towers, the coverage can be further enhanced along the rails.
Sorry, I no longer have the list of frequencies I used while on these trains, but I am sure you can find them on the internet like I did.
Have fun!
Tom, KR4BD
Lexington, KY
Lexington, KY
Sounds like you had a really great trip, Tom, on the Empire Builder from Chicago to Portland, and then on down on the Coast Starlight. I'm sure plugging in the frequencies, into your scanner, beforehand made it a lot easier and more fun.
I took the Coast Starlight up to Portland, then the Empire Builder from Portland to Whitefish, Mt, this past summer. It was a great trip, except for the fact we were 2-3 hrs late getting into just about every major stop.
I also am a ham operator (WA6ZFM). I purchased a Yaesu VX-5R hand-helf last spring..had a lot of fun with it on the train. I did try a few RR fequencies, but did not hear a thing (I will have to admit I didn't try the RR freq's very often..my main concern was working ham 2 meter repeaters along the way). A friend of mine suggested using an elongated rubber duck antenna instead of the one that comes with the VX-5R. I think it was good advice. I bought a Diamond SRH999 extended HT antenna (around 19 inches long) and it did make a big difference in receive amd makng repeater access. The cost of the thing (around $60) seems a little excessive, however.
Regarding reception distance for RR transmitter towers, there is a "rule of thumb" for 2 meter repeaters which can give you a rough extimate of maximum distance for acceptable receiving. I think it would apply to 160 mHz, as well.
If you take the square of the transmitter height and of the receiver height, add them together, then multiply times 1.4, you can get a rough idea of transmitter receive distance, in miles. For example, if you have 200 ft RR transmitter, the square of 200 is 14.1. Multiplying x 1.4 gives you around 20 miles (assuming you are receiving with a hand-held ..the receiver antenna height can be tossed aside).Again, this is a rough estimate and does not take into consideration transmitter power or antenna gain. If you had a transmitter antenna at 100 ft and you were using a receiver antenna at 9 feet, the max distance would be 10 (sq of 100) + 3 (sq. of 9 ft) = 13 x 1.4 or 19 miles.
There is a chart at:
http://www.artscipub.com/simpleton/simp.range.html
It figures in transmitter power and gain of the transmitter antenna, as well as the receive antenna, as well as height above ground for both.
Using the chart, at 50 watts and with a RR transmitter at 200 ft, you get about 24 miles range, figuring in no db antenna gain. (This is close to just figuring the square of 200 ft x 1.4). However, when you add antenna gain (you go up 1 line for every db gain) it sure makes a difference. The antennas for 2 meters offered by HRO, for example, seem to range from around 10 db gain up to 18 db gain. If the range for the 200 ft tower is up to 40 miles, it looks to me like you need close at least a 16 db gain, for the RR transmitter antenna, to get a 40 ft range. I wonder what sort of antennas they use? To get to a 45 mile range, it would go up to around 21 db. Do you know if the tower height varies? I am assuming the power output is no more than 100 watts (50 watts in the example). Of course, if the tower is higher than 200 ft the range would be significantly greater.
I guess you could say, in decliing order of importance for receive distance, the most important factors are 1. Height of the transmitter antenna 2. gain of the transmitting antenna 3. power.
73's
Dick
I took the Coast Starlight up to Portland, then the Empire Builder from Portland to Whitefish, Mt, this past summer. It was a great trip, except for the fact we were 2-3 hrs late getting into just about every major stop.
I also am a ham operator (WA6ZFM). I purchased a Yaesu VX-5R hand-helf last spring..had a lot of fun with it on the train. I did try a few RR fequencies, but did not hear a thing (I will have to admit I didn't try the RR freq's very often..my main concern was working ham 2 meter repeaters along the way). A friend of mine suggested using an elongated rubber duck antenna instead of the one that comes with the VX-5R. I think it was good advice. I bought a Diamond SRH999 extended HT antenna (around 19 inches long) and it did make a big difference in receive amd makng repeater access. The cost of the thing (around $60) seems a little excessive, however.
Regarding reception distance for RR transmitter towers, there is a "rule of thumb" for 2 meter repeaters which can give you a rough extimate of maximum distance for acceptable receiving. I think it would apply to 160 mHz, as well.
If you take the square of the transmitter height and of the receiver height, add them together, then multiply times 1.4, you can get a rough idea of transmitter receive distance, in miles. For example, if you have 200 ft RR transmitter, the square of 200 is 14.1. Multiplying x 1.4 gives you around 20 miles (assuming you are receiving with a hand-held ..the receiver antenna height can be tossed aside).Again, this is a rough estimate and does not take into consideration transmitter power or antenna gain. If you had a transmitter antenna at 100 ft and you were using a receiver antenna at 9 feet, the max distance would be 10 (sq of 100) + 3 (sq. of 9 ft) = 13 x 1.4 or 19 miles.
There is a chart at:
http://www.artscipub.com/simpleton/simp.range.html
It figures in transmitter power and gain of the transmitter antenna, as well as the receive antenna, as well as height above ground for both.
Using the chart, at 50 watts and with a RR transmitter at 200 ft, you get about 24 miles range, figuring in no db antenna gain. (This is close to just figuring the square of 200 ft x 1.4). However, when you add antenna gain (you go up 1 line for every db gain) it sure makes a difference. The antennas for 2 meters offered by HRO, for example, seem to range from around 10 db gain up to 18 db gain. If the range for the 200 ft tower is up to 40 miles, it looks to me like you need close at least a 16 db gain, for the RR transmitter antenna, to get a 40 ft range. I wonder what sort of antennas they use? To get to a 45 mile range, it would go up to around 21 db. Do you know if the tower height varies? I am assuming the power output is no more than 100 watts (50 watts in the example). Of course, if the tower is higher than 200 ft the range would be significantly greater.
I guess you could say, in decliing order of importance for receive distance, the most important factors are 1. Height of the transmitter antenna 2. gain of the transmitting antenna 3. power.
73's
Dick