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Tv in space

  1. Aug 4, 2006 #1
    if i were to turn on a tv on the hidden side of the moon, what would it look like?
    would the moon block the tv transmition?
    if it did, what would it still look like a snow storm?

    if not, then what if i turned on a tv in deep space?
    would i see just a small snowstorm?

  2. jcsd
  3. Aug 4, 2006 #2


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    I would think that even on the near side of the moon the signal would be to weak for your off the shelf TV receiver to get a useful signal.

    Any where outside of about 100km from a TV transmitter you would only see a "snowstorm" with a off the shelf TV. TV signals are very directional, to get a good signal you need to have very nearly a line of sight on the transmitting antenna. So the far side of the moon could not receive a meaningful signal. Therefore you would only see the "snowstorm".

    I guess you were not around for the early days of TV. We finally got a TV in 1956 when a transmitting tower was built on the top of a hill about 5mi from our home. WE could see the tower and got a beautiful signal. My cousin OTOH lived 15 miles away and was behind a hill which shadowed their home from the transmitter. They did not receive any signal from that station. This is why you see satellite dishes in areas many rural areas. It is not possible to receive a transmitted signal.
  4. Aug 4, 2006 #3


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    And more recently (but still before skywolf was born), the Apollo astronauts would lose communications when orbiting around the backside of the moon. I don't think there's any way to avoid that. Well, unless we learn to make neutrino transceivers that fit on a spacecraft. That would be a fun project to work on.....
  5. Aug 4, 2006 #4


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    Over-the-air (OTA) TV reception can be very difficult for people living in mountain valleys, because the mountains get in the way. Most of the stations that serve western North Carolina operate several low-power "translators" that re-broadcast their signal to serve specific towns. I'm sure this is common in other mountainous areas.

    The back side of the moon would be a great place to put a radio telescope because the moon would block most of the interference from terrestrial sources!
  6. Aug 5, 2006 #5


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    You'd still get a snowstorm, because that static is largely made from the Cosmic Background Radiation.

    If attemting this on the far side of the Moon; get Cable!
  7. Aug 5, 2006 #6


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    Assumed: All tvs have CRTs.
    Do all tvs have antennas? I always think of the television as just the CRT part, and not a cable descrabler in addition or something like that.
  8. Aug 5, 2006 #7


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    I've read that here in the USA, about 85% of the population uses cable or satellite as their primary source of TV. I'm among the other 15% that uses only terrestrial broadcasts. But I don't get any "snow" even though most of my stations are > 60 miles (100 km) away, because for the last year I've been using digital TV (including high-definition) instead of analog. If you can keep the signal strength above a certain threshold, reception is perfect. I have to use a good antenna on the roof for this, but I had to use one anyway for a halfway decent analog picture.
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