Question about TV channels

[Kanchou]

A lot of the channels and shows I watch on my TV often have a really nasty afterimage that ruins the quality of the picture...

Is this normal? It primarily happens during anime shows on certain channels (Like TBS and TV Tokyo), but it also happens on some live-action shows too.

Are there anyway ways to fix it, or is it completely 'shou ga nai?'

[Big Booger]

Are you sure it is not your TV? I don't get that crap with either skyperfect TV or the basic TV (NHK and all the rest)...

[Charles]

I will guess you're using terrestrial TV with an antenna. This is a classic effect known as "multipath interference." There is some nearby huge object, like a mountain or a large building, that is partially reflecting the TV signal. The reflected signal is delayed slightly from the direct signal, causing a weird intereference pattern in the direct signal, which distinctively appears as a ghostly afterimage a bit offset from the main image.
There used to be elaborate antenna rigs and attenuators to reduce the effect, you could buy them at any TV store, but nowadays, TV antennas are a lost art. The solution: move to some place that doesn't have a nearby object to interfere with the signal. Or just get cable/sat TV and ditch the antenna.
Let me know if my guess about your antenna is correct. There is also a possibility you're just watching a show with really a bad telecine job, in which case there is nothing you can do about it.

BTW, can you tell I'm an old TV hacker that used to make my own antennas to deal with multipath distortion? They worked pretty well, I used to pick up stations from 500 miles away, at night when the local stations went off the air. As far as I'm concerned, TV hardware has gone downhill continuously since the days when you could remove all the tubes and take them down to Woolworth's and stick them in the tube tester.

[GuyJean]

I will guess you're using terrestrial TV with an antenna. This is a classic effect known as "multipath interference." There is some nearby huge object, like a mountain or a large building, that is partially reflecting the TV signal.

You seem to know a lot obout 'reception'.. I have a question:

I'm still living around the same train station and area, but I moved to a new apartment a couple weeks ago. At my old apartment, I could receive channel 2 and 5, which, I believe, are local Yokohama channels. At my new place, those same channels are nothing but static. Could this be because my new place doesn't have a UHF or VHF antenna, whereas my old apartment building had both? Would it be best to contact the stations themselves?... I think one station was called MX Tokyo, or something.

Thanks in advance..

GJ

[Taro Toporific]

...At my old apartment, I could receive channel 2 and 5, which, I believe, are local Yokohama channels. At my new place, those same channels are nothing but static. Could this be because my new place doesn't have a UHF or VHF antenna, whereas my old apartment building had both? Would it be best to contact the stations themselves?...

The TV stations could not give a sheeeeee-it, EXCEPT the kind folks at NHK. If you are paying for NHK, you could call NHK and they would be more than happy to check your place out, hee, hee.

Seriously, your area by the station is a VHF/UHF reception chamber of horrors. It's in sort of a hollow with a lot of steel construction all around. Without a building antenna, you cannot expect any reception.

I assume, your new apartment has Tokyu Cable as most buildings by your station. You're gonna have to pay to get real reception since building landlords DETEST giving permission for you to put up your own VHF/UHF antenna.

As a warning to other folks, many old apartment buildings have trashed common antennas. Simple things like a bad cabling or junction box can kill your reception. Often it takes just 1,000 yen for new connectors to fix your problem and many fudo-san will get this fixed for free for you if complain when you first move into a new building. Also as I said before, NHK will troubleshoot reception problems for "free" and do a damn good job about it --- the problem is they will want you to pay for NHK.

[Charles]

I'll defer to Taro since he seems to know your local conditions. Not much you can do in the middle of a canyon, be it metal buildings, or rock. In fact, that's why they invented cable TV in the first place.
The usual ways to address your reception problem are simple: get your antenna up higher than the obstructions (impractical in most cases), or buy highly directional antennas, one for each broadcast source (which won't work if the line-of-sight to the broadcaster is obstructed). Most people just get an omnidirectional antenna, which picks up everything, including multipath distortion signals which can kill weak signals. Directional antennas reject signals from off-axis, so it eliminates the bounce. Unfortunately, you need one directional antenna pointed at each TV station, so this begins to add up to some bucks quickly. I don't even know where I'd begin to look for specialized TV antennas nowadays, like I said, it's becoming a lost art.

[GuyJean]

Thanks guys.. I realize it has a lot to do with local surroundings; I was raised in the woods of Oregon, and got 2 and a half channels, in black and white, most of my life... I thought it might be a quick fix by purchasing either a UHF or VHF antenna.

It's an old apartment building, so maybe I'll speak with the manager.. Cable's an option, but I'm not impressed with most the channels offered. BS has just enough bs to keep me happy; sports, West Wing, Monk, Nightline, and the movies keep me happy enough..

GJ

[Taro Toporific]

[Charles]

Oh.. I forgot one cool solution. My grandmother's house was way out in the boonies and she could not get good reception with an omni antenna, so she had a single directional antenna up the roof, with a motor so you could point the antenna different directions. There was a little box with a dial marked like a compass, it sent control signals up to the antenna motor to rotate the antenna mast so the directional antenna could point in any direction. This eliminates the need for multiple antennas, but at a cost of complexity in another area. Fortunately, it's a lot simpler (and cheaper) to rig the motor than to integrate multiple antennas. I don't know if anyone sells stuff like this anymore, that antenna rig surely dated back to the early 1960s.

[Taro Toporific]

Oh.. I forgot one cool solution... it's a lot simpler (and cheaper) to rig the motor than to integrate multiple antennas. I don't know if anyone sells stuff like this anymore, that antenna rig surely dated back to the early 1960s.

Rotators are still sold in Akihabara for ham radio. Come to think of it, Akihabara has a few specialized antenna shops.

[Kanchou]

The TV is plugged into a cable outlet in the wall, but I don't know if my building has an antenna or is using cable.

If it has a roof-top antenna there shouldn't be many problems since the building is 9 stores tall, and not close to many other buildings taller than it (within a few hundred meters at least). The nearest station is also a little over a kilo away.

Now it seems to be ok, except for most of the anime shows...

[Taro Toporific]

The TV is plugged into a cable outlet in the wall, but I don't know if my building has an antenna or is using cable....

Call your fudo-san rental agent. This is one of few things you can get fixed for free. Most likely it's a simple connector/outlet problem, so of course check your own connections first.

Besides asking one of your neighbors how their connection is, you ought to try a different cable/connnector to your cable outlet. If that doesn't work, you could borrow someone's small TV and test your reception with a different cable/connnector. Also open and look into the cable outlet for rust and corrosion---scrape all the connections clean. Bad COAX cable connections are a common problem everywhere. Because of the standard CRAP construction methods in Japan, water condensation rusting out the cable outlet in the walls is a major problem.

[omae mona]

Besides cable... since you're apparently in Tokyo, you're in one of the three zones in Japan that has terrestrial digital broadcasts since last December. You should be able to run over to your electronics store and pick up a digital tuner (or a whole new digital-ready TV) . This should give you the same channels, in hivision, without the ghosting problem. I get these digital broadcasts via cable, so I haven't tried that hardware combination myself, but I believe the above is how it's supposed to work.

Anybody priced out these tuners yet? Anybody have experience on whether the digital signal comes through clean on a home-mounted antenna?

[Taro Toporific]

Anybody priced out these tuners yet? Anybody have experience on whether the digital signal comes through clean on a home-mounted antenna?

You'll have to pry my analog HiVision out of my cold dead fingers.
Digital TV means I would have to pay for NHK (the digital NHK signal is scrambled).
I'm sure the reception is better and much stronger than analog but digital TV is going to include all sorts of nasty DRM. There's a couple FGs here who have been nailed by NHK when they bought a new digital TV. However, sooner or later, we all we will need to buy flat-screen TV for the huge energy savings and the fact that analog broadcasting will end around 2010.

[omae mona]

You'll have to pry my analog HiVision outfrom cold dead fingers.
Digital TV means I would have to pay for NHK (the digital NHK signal is scrambled).

Maybe it's because I was getting it delivered via cable, but even with the B-CAS card inserted, it was never scrambled for me during the time before I started paying. Granted, the screen eventually started showing an annoying message saying "please call NHK". Around the same time, I decided to pay the NHK guy anyway (not because of the message on the screen, but because the 5-times-a-day doorbell ringing was getting annoying).

I'm sure the reception is better and much stronger than analog but digital TV is going to include all sorts of nasty DRM.

Yes, but remember the DRM only can affect digital copying. If you're content to do analog copies - which is no worse than sticking with the analog broadcast in the first place - there's nothing they can do to stop you (so far as I can tell!)


FYI, I recently discovered one actual benefit to the digital broadcasts besides the picture quality and data channels. Namely, they can split their bandwidth across channels when they decide to, thereby increasing the number of available channels at different points in the day. Lately it's not uncommon for NHK Kyoiku (normally analog channel 2 I guess) to be split into channel 21, 22, and 23, each showing different shows at the same time (but not in hivision). This feature is true of all the channels, not just NHK, but NHK is the only one that seems to do it regularly.

[Kanchou]

Well, my building (a dorm) has an NHK emblem, which I assume means that the company pays it's NHK fees...

So maybe I'll look into the digital tuner thingy...

[Taro Toporific]

Well, my building (a dorm) has an NHK emblem, which I assume means that the company pays it's NHK fees...
So maybe I'll look into the digital tuner thingy...

Nooooooo. If it's company dorm, you can ask around for help and they will straight out everything for free: IT'S THEIR JOB.

[Kanchou]

No... the dorm's company. It's a private dorm ran by a dorm company. Not a company dorm.

I'm not a salaryman just quite yet... thank god...