Ditigal TV reception on trains
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Why would you want to watch TV when there is so much to see out the window?
I have a hand held tv (analog, useless now) that I used along the Auto Train route. I found that I could get a decent signal as we approached and moved away from major cities (Richmond, Jacksonville, etc.). When the train was right near downtown, the signal strength was about what I could get at home with the rabbit ears adjusted properly.
Ispolkom
Engineer
I have to use a directional tuner at home to pick up signals. Would you have to move the laptop to continue to receive?
Upstate
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Yeah, scenery this and scenery that. If I really wanted to see something I would go backpacking and look off a mountain that no one can see off of unless they hike up there and earn it. Here is the deal, Amtrak has great prices between Atlanta and New Orleans and I like good coffee, good food and drinking from a plastic cup while walking down the street. I am not taking this train so I can grope the window.Why would you want to watch TV when there is so much to see out the window?
Upstate
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The antenna that came with it is a remote collapsible upright. It can pick up a few stations inside at home, I just wonder if anything can get through the train car.
wayman
Engineer
To be fair, there are a few Amtrak routes that pass through mountains which are many, many miles from any roads or trails--the only way to see them actually is by train, unless you're willing to hike and/or raft for days off-trail.Yeah, scenery this and scenery that. If I really wanted to see something I would go backpacking and look off a mountain that no one can see off of unless they hike up there and earn it. Here is the deal, Amtrak has great prices between Atlanta and New Orleans and I like good coffee, good food and drinking from a plastic cup while walking down the street. I am not taking this train so I can grope the window.Why would you want to watch TV when there is so much to see out the window?
But you're right, none of them are between Atlanta and New Orleans
Nor in my neck-of-the-woods, the southern half of the NEC--I spend nearly every minute of every PHL-WAS or PHL-NYP trip reading, typing, or eating. I always go for a window seat, but only so I can have easier access to the power outlets 
Not to be sarcastic or holier than thou, but some of the tree top airlines have cheap fares and
Greyhound(LOL)also probably can get you to the Big Easy (no nurt feelings for natives in
NOL please!)cheap if not quick! You could always watch movies or even write a trip report
for us to enjoy since possibly you read this forum cause you enjoy/like trains!Theres not much
scenery between Atlanta and NOL but there are people to meet,cool drinks to enjoy, a bite
or two in the diner and a chance to unwind while cruising the rails!And what possibly could
be on in the summer that you couldnt do without for a few hours?I dont get this,have you
ridden a LD before, this is not the NEC or the CZ across Wyoming!Enjoy the trip,give us a
report since you have the computer capability!Oh yeah, the new phones get TV also but
Im not a techie, perhaps our tech mavens can advise about this?
Greyhound(LOL)also probably can get you to the Big Easy (no nurt feelings for natives in
NOL please!)cheap if not quick! You could always watch movies or even write a trip report
for us to enjoy since possibly you read this forum cause you enjoy/like trains!Theres not much
scenery between Atlanta and NOL but there are people to meet,cool drinks to enjoy, a bite
or two in the diner and a chance to unwind while cruising the rails!And what possibly could
be on in the summer that you couldnt do without for a few hours?I dont get this,have you
ridden a LD before, this is not the NEC or the CZ across Wyoming!Enjoy the trip,give us a
report since you have the computer capability!Oh yeah, the new phones get TV also but
Im not a techie, perhaps our tech mavens can advise about this?
Upstate
Lead Service Attendant
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- Feb 21, 2009
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- 405
A quick check of Travelocity and Greyhound finds that the only price that beats Amtrak is a 21 day advance non refundable Greyhound and even then its only 18 bucks you are saving. On top of that Greyhound is usually pretty nasty and the seats are just as cramped as the airlines. Airlines are wanting about 200 RT before taxes. Its pretty easy to find a low bucket 58 dollar fare for ATL-NOL on Amtrak. Now since my brother is traveling with me we have invested in a roomette which can easily be had for 47 bucks between these cities and we get all three meals for both of us (if it is on time at ATL). Airlines can beat Amtrak on time between these cities, but other than that Amtrak is holding all the cards.
Ispolkom
Engineer
That's a great price, since you'd almost break even on meals with just one person in the roomette. With 2 passengers you're coming out far ahead!
From a technical standpoint, my guess would be that in urban and suburban areas you would have a chance of reception, but given that almost all of the HDTV signals are UHF, the motion of the train would create a very rapid flutter on the incoming signal, made worse by moving between tall buildings. Signal peaks and valleys occur as a result of exact distance, in quarter-wavelengths, between the transmitting and receiving antennae. So at a given relative velocity toward or away from the transmitting station, the higher the transmitted frequency, the faster, in quarter-wavelengths per unit of time, are the peaks and valleys of received signal strength. Add to that a bunch of tall buildings either breaking the signal path or substituting a bounced signal path, and I would expect a lot of momentary unlocks in the digital data stream that the HDTV signals are made of. Which, since the HDTV displays the most recently received digital frame (frame buffer), would probably result in a lot of stutter, where the picture would jerk from one frame to another several seconds later, or to a lot of partially updated frames, where some of the pixels from a succeeding digital frame are updated into a preceding complete frame. There would also be some Doppler shifting going on, depending not on the speed of the train but on the relative velocity of the train car to or from the transmitting antenna. I don't know if that would be sufficient to cause trouble or not. I would expect better reception from the upper deck of a Superliner car, as it would mostly be above foliage. Heavy foliage attenuates UHF signals more than VHF (or lower) signals. Even given all that, if you are traveling within line-of-sight of a mountaintop or very tall (1,500'+) HDTV transmitting antenna site, and do not have heavy foliage or other intervening obstacles obstructing the path, you would probably have some sort of reception. The concern we have down here in "hurricane country" is that our battery-powered portable TVs are now useless pieces of junk that will no longer provide us with weather info (like radar and satellite pix) from our local tv broadcast stations) during hurricane power-outages, and I haven't seen much in the way of battery-powered small HDTVs yet. I do have a HDTV USB dongle from Pinnacle that works pretty well on a fast laptop, but the laptop obviously requires frequent recharging - it can't use AAs or Cs or D batteries that you can have a prepurchased stash of for emergency use.
I've been a licensed ham operator now for 40+ years and also worked in NASA and theU.S. Navy in commo.
I've been a licensed ham operator now for 40+ years and also worked in NASA and theU.S. Navy in commo.
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guest00
Guest
Considering that digital TV is far less powerful than analog, and you're going to be a distance from cities - I'd say no.
Here, 50 miles from Atl., analog got about 8 stations. Now that we're all digital: 3 (2 PBS, 1 GPTV) no news, sports, soaps, or anything.
And if anything moves in the room, the pix locks up for a few seconds.
So, in a moving, metal car, miles from the transmitter?
What are your chances of that working?
Here, 50 miles from Atl., analog got about 8 stations. Now that we're all digital: 3 (2 PBS, 1 GPTV) no news, sports, soaps, or anything.
And if anything moves in the room, the pix locks up for a few seconds.
So, in a moving, metal car, miles from the transmitter?
What are your chances of that working?
That's interesting. With analog and living near Lexington, KY I could only pick up Lexington stations. Now, with digital I can also pick up some of the Louisville stations, 70 miles away! I do have a little altitude where I live but not so much it should make much of a difference.
T
Tony
Guest
Because the keep turning off the scenery right after sunset. :angry:Why would you want to watch TV when there is so much to see out the window?
had8ley
Engineer
For $39.95 you can get the much bigger accessible "H" room 15 days before train departure if no one else has booked it and every other room is booked.
How about DVD's? Or if you can download a few movies from Itunes. This would be more reliable viewing than TV. Now if you are counting on watching a specific TV show on the day of travel, I would not do that. I would Tivo it and hope that somebody did not tell you about it like my sister told me the score to the Bear's game a few years back. I cussed her for about 5 minutes that day. LOL
Also, I think it is important to remember that not everybody who posts on here has the same enthusiasm for trains as we do. They might appreciate some aspects, but could careless about the scenery even if they are riding the CZ through Glenwood Canyon. I think it is important to respect all types when they post. We informally represent rail travel, and we need to do better than we did with this person.
Also, I think it is important to remember that not everybody who posts on here has the same enthusiasm for trains as we do. They might appreciate some aspects, but could careless about the scenery even if they are riding the CZ through Glenwood Canyon. I think it is important to respect all types when they post. We informally represent rail travel, and we need to do better than we did with this person.
Exactly. Next time you are on a train look around and see how many people are not looking out of the window, even if the scenery is amazing.
the_traveler
Engineer
But some nights, they turn on the moon!Because the keep turning off the scenery right after sunset. :angry:Why would you want to watch TV when there is so much to see out the window?
I seem to recall that a certain California town has just recently turned OFF the "moon"........ :lol: :lol: :lol: :lol:
Even if you can get a good enough signal through the windows, it is likely not to work very well, if at all, when the train is moving at much speed. The 8-VSB modulation scheme for ATSC (digital) TV broadcasting was not designed to handle any significant doppler shift. It has been known since the ATSC format specs were defined in the mid-90s that it would not work well for digital tuners and TVs in moving cars or RVs. of course, there is also the issue of having to do a channel scan as you move through different areas, but if you know the physical RF channel of the local stations and have a tuner that allows manual entry, you can try to get stations one at a time. There is a mobile TV standard that has been grafted on top on 8-VSB which does allow reception while moving, but stations will use this for low Rezz SD broadcasts to cell phones or portable devices. Of course, the mobile TV broadcasts embedded in the ATSC signal will take away bandwidth from the HD sub-channel, but the picture quality of HD broadcasts have been going downhill for years as stations cram in more sub-channels.
There are several other common mis-conceptions in this thread I wish to correct.
1. Digital TV broadcasting is not weaker than analog. Many analog UHF stations have increased their coverage area because the FCC allowed digital UHF to have a 1000 kW max power to help the low VHF stations moving to UHF compensate for the loss in coverage. Analog UHF had a maximum power of 5000 kW, but because digital ERP (Effective Radiated Power) is calculate differently than analog, the digital equivalent of 5000 kW was approx 350 kW (~16:1 ratio in ERP). A UHF station that had a 2000 or 3500 kW analog signal has a far stronger signal if they managed to snag a 1000 kW digital ERP level. The biggest problem in digital reception has been with the stations that moved their digital broadcast back to their upper VHF (7-13) analog channel, but ended up with inadequate power levels because of other stations that also got VHF channel assignments. The issue with digital reception is the cliff effect and a lot of people who were satisfied with noisy analog pictures found themselves on the wrong side of the cliff. A better antenna setup often fixes that.
2. Digital TV broadcasting is hardly almost all on UHF. Now that the transition is over and some 500+ stations flash cut back to their analog channel this year, the breakdown for the 1823 full power digital stations by their physical RF channels is: low VHF (2-6) = 40 stations, upper VHF (7-13) = 449 stations, and UHF 14-51 = 1334 stations. Few stations opted to go to low VHF for digital broadcasting because low VHF is prone to impulse interference which breaks up digital reception. BTW, the channels that were taken away from full power TV broadcasting were UHF 52 to 69 (the 700 MHz auction people may recall reading about). Post transition digital TV broadcasting is from channels 2 to 51.
the_traveler
Engineer
If it is known that it does not work well in moving cars or RV's how does things like Direct TV work in planes? :huh: I assume Direct TV broadcast digitally, and I have yet to see an RV moving as fast as a 757!
Bierboy
OBS Chief
Wow....amen to that.Why would you want to watch TV when there is so much to see out the window?
Ka and Ku satellite broadcasts using DVB-S protocol are an entirely different beast than a 6 MHz wide ATSC broadcast signal.If it is known that it does not work well in moving cars or RV's how does things like Direct TV work in planes? :huh: I assume Direct TV broadcast digitally, and I have yet to see an RV moving as fast as a 757!
And if you travel in December, they turn on the Christmas lights.But some nights, they turn on the moon!Because the keep turning off the scenery right after sunset. :angry:Why would you want to watch TV when there is so much to see out the window?
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