Help for Noob - Rail Propagation Questions

[i-Scan]

I am thinking of adding an antenna dedicated to receive rail frequencies. My home is located on flat land about 5 miles from CSX/Amtrack lines and within the last 15 miles of rail in Newport News, VA. I'm using SDRs (Multiple RTL and an Air Spy with and without the SpyVerter for general scanning all omnidirectional and wide-band antennas.) and getting only a bit of rail radio traffic which is only from a dispatcher.

I'm thinking to put up a directional antenna dedicated for rail. Should the design be Uda-Yagi for 161-ish MHz that is vertically polarized, pointed in the direction of the longest course of travel? From how much distance could I expect to receive? I welcome suggestions what to do to receive radio from rail running to and from Norfolk from home (STARTS about 30 miles from home.) Is all or part of this about a hopeless waste of effort?

 

[trap5858]

You might just give it a try with the current equipment you are using. Most transportation systems have good coverage.

 

[reconrider8]

I wouldn't do a yagi as trains are constantly on the move and railroads don't use repeaters. I would get an omnidirectional up as high as possible.

 

[N5XTC]

I am thinking of adding an antenna dedicated to receive rail frequencies. My home is located on flat land about 5 miles from CSX/Amtrack lines and within the last 15 miles of rail in Newport News, VA. I'm using SDRs (Multiple RTL and an Air Spy with and without the SpyVerter for general scanning all omnidirectional and wide-band antennas.) and getting only a bit of rail radio traffic which is only from a dispatcher.

I'm thinking to put up a directional antenna dedicated for rail. Should the design be Uda-Yagi for 161-ish MHz that is vertically polarized, pointed in the direction of the longest course of travel? From how much distance could I expect to receive? I welcome suggestions what to do to receive radio from rail running to and from Norfolk from home (STARTS about 30 miles from home.) Is all or part of this about a hopeless waste of effort?

we are in the same area. i am in hampton and i hear railroad just fine using an internal antenna on many of my scanners. my pro 197 is hooked to an external antenna and pulls them in nicely. not much to listen to IMOP. not much chit chat. kind of like military air. but, to each his own. we all cant wear black and ride the same motorcycle. lol. it is good to meet another LOCAL scanner enthusiast.

 

[i-Scan]

Getting off the ground

OhhhKay... I might still become a railfan as soon as I figure it out. One or two people on two rails moving megatons of time-tested transportation technology through miles of nowhere so seemingly alone, how more fascinating can it get?

Thanks to trap5858, reconrider8, and N5XTC
Not a HAM, so I have stuff to learn. Who knows how tall an antenna mast clears the roof of a house on a slab? My antennas are not so elevated. All are inside a 2 story-home and I would like to erect a new Tram 1410 Broad Band Discone/Scanner Base Antenna to stay in the weather. I typically hear scant chit chat from an engineer to dispatcher, no more than once a day there is a call to throw a switch in Lee Hall and confirm. So I thought I was just not hearing anything that was not in the last few miles of line. It seems there should be some talk from switching yards around all these marine ports and naval stations but I haven't found it.

Maybe some old unwanted or junked analog VHF TV antenna wants new life mechanically tuned just below Channel 7. I think director elements decrease spacing along with frequency and shortening lengths of "driven," and reflector elements. That's kind of what I had in mind to put under a new Tram 1410.

N5XTC, there are other things to hear while waiting. It is great to find others who are local. Curious, do you log receptions other than amateur radio? If so, do you use pen and paper form log pages? Cool call sign!

 

[radionut44]

You can buy a Baofeng UV82 for less than $30.00. Not likely you will need to program more than a few frequencies, but I think you will find it receives better than a scanner. It will not scan as fast as a scanner, but for just a few frequencies mine does fine.

 

[i-Scan]

Thank you Radionut44,

Buy a Baofeng UV82 for less than $30.00 I had no idea it could be so painless to get into. Use it as a portable rail scanner that could be dedicated to rail frequencies while I use other receivers to scan anything else. Plus I could just go take some exams and truly wear the thing out. Now here's a really fine deal.

 

[cbehr91]

Actually, a Yagi may help in your case if you are looking to receive transmissions in a given direction. If you are close enough there is usually enough on the rear lobes to receive transmissions in the opposite direction.

 

[i-Scan]

Yagi

That's exactly what I was thinking. It is 14 or so miles into the opposite direction lobe. I'm going to build these myself. I also thought of putting mirrored elements back to back on one boom to share the reflective element. Maybe use a few more director elements in the forward direction. I'm thinking that more reception traffic may be from the reverse direction if reception of Norfolk ports reaches this far. BUT, my only reception was from the opposite lobe direction and has been scant. (Were the application not about scanning, a rotator might have served.)

I have seen some pre-made J-pole and Slim Jims in the Rail band range from the internet. I don't think that they are at all directional. Though it may not matter so much in comparison with the above antenna of my design/thinking.

 

[N9JIG]

Just to throw a little wrench into the works: Some railroad lineside bases use directional antennas to groom the signal along the tracks. This might mess with you if you are broadside to these antennas. While you may still here them at some distance, even off the sides of the antenna the distance would be quite a bit less than in line.

Hotbox and other detectors usually transmit with lower power and often with very basic antennas so their range is limited even if the radiation patterns are fairly omni-directional. Sometimes it is just a quarter-wave style mobile antenna mounted on the equipment cabinet but sometimes they are more substantial.

Locomotive radios often have inefficient antennas as well so their range is pretty limited at times but again, YMMV.

I usually have a radio scanning all the VHF railroad channels. While RR activity here is somewhat limited I do find a new channel here and there and when conditions arise I start hearing stuff from greater distances.

You are right to focus on your antenna. Nothing beats a good antenna other than a good antenna at a higher elevation. If all your railroad activity is from the same direction then a yagi will help but if it is from multiple directions a good omni antenna works better.

 

[i-Scan]

Decisions?!?

Just to throw a little wrench into the works: Some railroad lineside bases use directional antennas to groom the signal along the tracks. This might mess with you if you are broadside to these antennas. While you may still here them at some distance, even off the sides of the antenna the distance would be quite a bit less than in line.

Hotbox and other detectors usually transmit with lower power and often with very basic antennas so their range is limited even if the radiation patterns are fairly omni-directional. Sometimes it is just a quarter-wave style mobile antenna mounted on the equipment cabinet but sometimes they are more substantial.

Locomotive radios often have inefficient antennas as well so their range is pretty limited at times but again, YMMV.

I usually have a radio scanning all the VHF railroad channels. While RR activity here is somewhat limited I do find a new channel here and there and when conditions arise I start hearing stuff from greater distances.

You are right to focus on your antenna. Nothing beats a good antenna other than a good antenna at a higher elevation. If all your railroad activity is from the same direction then a yagi will help but if it is from multiple directions a good omni antenna works better.

I want to put them near to 40 feet high. I have a Tram 1410 Broad Band Discone/Scanner Base Antenna, Omnidirectional, that's been waiting for a mast and put my Air-Spy and Spy-Verter on that feed.

Bi-Directional yagi tuned for rail... I think I will try to roll my own Yagi that two sets of driven and director elements share the same reflector and feeds will run separately to two RTL-SDRs.

Or Tuned Omni... Then there are all-tuned-up-for-rail commercial J-Pole ideas...tuning on my side on with a second omnidirectional...I could buy either of those and skip time-consuming design and construction projects!

I have a question for amateur radio guys... For rail frequencies where should I put the balun, on the antenna? Or on the SDR? (I could sidestep and put SDRs on the antenna. Just run 50 feet of USB-with boosters or run Ethernet from a Raspberry Pi on the antenna instead of 50-foot feed lines. But that all sounds way too extravagant for what I expect may not be much reception at all.) Yagis have 400-ohm impedence and RTL-SDRs are 75-ohm, designed for TV. Is the best signal available from a run of more 400-ohm twin line or more 75-ohm coax? And then, if you have experience with J-Poles or Slim-Jims...yeah.

 

[i-Scan]

Baofeng UV82 for less than $30.00

You can buy a Baofeng UV82 for less than $30.00. Not likely you will need to program more than a few frequencies, but I think you will find it receives better than a scanner. It will not scan as fast as a scanner, but for just a few frequencies mine does fine.

Here we go, I did it. It's on the way to arrive tomorrow. Sooo many thanks!

 

[i-Scan]

Progress to report...

You can buy a Baofeng UV82 for less than $30.00. Not likely you will need to program more than a few frequencies, but I think you will find it receives better than a scanner. It will not scan as fast as a scanner, but for just a few frequencies mine does fine.

Thought you should know... Along with your suggestion, I have a Baofeng UV82 programmed (with transmitting defeated) to scan local Rail frequencies. It is running absolutely great just as you said! Further, I discovered that a better or more elevated base antenna will most likely help somewhat. A few drives near the railyard with the UV82 turned up that there is more than I had been receiving but not so much more to hear as I had suspected.

SO, your suggestion has had the most dramatic practical impact upon my railroad monitoring of anything that I have tried.

PLUS, I have the UV82 as a portable scanner for trips.

PLUS, I'm ready to take the ham Technician's exam and studying for the ham General exam, then maybe the Extra as I wait for a volunteer exam session to open up. (I over accessorized the UV82 with no idea whether I really want to pursue a ham hobby. But then, rail relates more to some deep inward feeling than to my intellect and has not changed much since I was about 4-years old. I probably just need more rail.)

 

[radionut44]

Same path

I bought my UV82 to listen to railroads, but then decided to take tech test to be able to use 2 meters and 70cm. Bought radio in June, passed Technician test in July, passed General and Extra tests in August and rewarded myself with an Icom IC-7300 HF radio. Having a great time with both hobbies!
Ron

 

[N5XTC]

great that you got your ticket and advanced past technician level. definitely more to do with the general class license as far as band privileges are concerned if you are into HF. not all "hams" are. I surely am.