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How to convert the new digital on air signal for old tv system?

  1. Mar 22, 2013 #1
    I always record all my tv programs and watch it in much later time. I am actually like a year and half behind the current schedules ( I just started the 2011-2012 season!!). The advantages are I can skip commercials and the most important thing, I can watch the coat hanger season finale and watch the result without waiting!!!:rofl: Without a big antenna up on top of the roof, the tv reception in my area is bad. Currently I have Direct tv with 4 stations so I can set up to 4 DVD recorders at one time. But in reality, 90% of the show I watch are available on air. I am thinking about putting some money to install a roof antenna and buy a converter box so I can tape some of the show directly from air and cut down on the number of Direct tv stations as they raise the price for each additional station. I don't exactly want to get into DVR using hard drive as it is too important that I don't want to risk one hard disk failure and lost the whole season's recording, I rather have them in separate DVDs. So..........

    I want to install a new Digital antenna and convert the signal so I can use it for the older VCR and non HD DVD recorders. I know I need to first install a HD digital tv antenna, then buy a converter box.

    My question is if I have multiple VCRs and DVD recorders in different room, do I need to buy multiple converter boxes one for each room. How does the converter box work? Do you need to tune the converter box to particular channel to watch ( eg. channel 7 for ABC here). Or the converter box just convert the RF signals of all channels and feed it to the tv tuner, then you can tune to a particular channel with the VCR or tv.

    If I need one converter box in each room, then the cost is going to have to add on top of the antenna. I am first doing a cost analysis to see whether it's even worth considering.


  2. jcsd
  3. Mar 22, 2013 #2

    jim hardy

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    Digital TV mostly uses the old UHF frequencies plus some a bit higher.
    A very few stations stayed on their old VHF channels.
    So your old antenna will do fine.
    At my place in Idaho i made a simple folded dipole and mounted it to rooftop airconditioner unit. No holes in the roof.
    At those frequencies a half wave is only about ten inches. Used 1" PVC pipe and #10 solid copper wire, and a 300::75 ohm balun TV antenna transformer(50 cents at thrift shop, $5 at Radio shack).
    I made mine 3/2 wave for average of my local stations, because most of them were tolerably close in frequency. Folded dipole is fairly broad. That way it worked out ~1/2 wave for one of them that was way lower.
    My antenna is about 27 inches.
    Works great. Gets about ten stations.

    However - the TV stations kept their old channel number - the channel number is no longer associated with the frequency.
    So you need to find on web a listing of stations in your area and what is the actual frequency they broadcast on.
    This site used to be great. Not what it used to be but I just tried it - give it your address and it tells you what direction to the stations and gives both their true RF channel number and the channel number they pretend to be.


    Google used to have a page for aiming your antenna that gave you a satellite view of your house with pointers to local stations but I cannot find it anymore.

    In my neck of the woods, old channel 19 is now on RF channel 20 but channel 8 stayed on RF channel 8 . So here in Arkanasas I still need a looonnggg antenna.

    I had a $39 GE converter box that scans and tells you what actual frequencies it found stations on.
    The converter box receives one channel and puts out RF or NTSC composite.. You tune it with a remote. If you find a box with buttons it's handy because the remotes always hide someplace.

    You might find your local channel seven on the old channel 7 VHF frequency
    or you might find it anywhere else.

    If antennaweb isn't helpful, try these...

    this one looks pretty good ! gives same as antennaweb but easier.



    good luck

    old jim
  4. Mar 22, 2013 #3
    Thanks Jim for all the info.

    I don't have an antenna on the roof, so that money has to be spent. From what you described, the converter box actually is the one to tune to the specific channel. This mean if I have 4 recorder stations, I do need 4 individual converters to tune to 4 individual channel.
    Last edited: Mar 22, 2013
  5. Mar 22, 2013 #4

    jim hardy

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    Yes, I am unaware of a tuner that'll receive multiple channels at once.
    Check local thrift shops.

    Don't buy an expensive antenna until you experiment. Mine cost under $10 buying everything new at Ace hardware.
    Reception was iffy indoors so I put it on the roof. Used conduit clamps to mount it. The 50 foot cable cost way more than the antenna...
    The neighbors were awed - they have expensive manufactured yagis and no better reception.
    Unless you're way out in the fringe , keep it simple...

    have fun - I sure did.
    Last edited: Mar 22, 2013
  6. Mar 23, 2013 #5
    Ha ha!!! I am extremely afraid of height. In my book, they earn the money!!! I know indoor won't work as I tried before they change the system, so it has to be up 20ft high on the chimney above the second floor!!:eek:

    Thanks for the info, now I know a lot better how much it will cost......say $250 for the antenna installation, $40 per station. Most likely they are going to piggy back the signal into the coax of the Direct TV.


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