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Discussion Starter · #1 ·
Is there a way to wirelessly transmit an antenna signal say 150 feet? I see a lot of products such as the terk leapfrog, but I don't know if it would work with an antenna. Sorry if this was already mentioned somewhere.


Thanks
 

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Not really.
 

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Good question. If a leapfrog simply tunes a broadcast channel, filters it, and heterodyne converts it to a higher frequency for rebroadcast, it just might work with a digital channel, since the filtering in such a device would be primitive and unlikely to damage the digital waveform, but I've never tried it. I haven't seen any consumer device actually marketed as a digital, single channel repeater yet.


I think the "X factor" in this would be frequency stability and lock. Analog tuners have "capture ranges" that allow them to lock onto any signal within a couple of MHz of the selected one, and they look for the visual carrier. If a consumer repeater has AFC on its input but doesn't find a visual carrier, it might not end its scan of that frequency range right on the nose as far as the tuned frequency is concerned, or it might react to a failure to lock by rescanning every so many seconds. Twenty five years ago, when cable TV boxes and TV tuners were even more primitive than they are now, I did business with a sportsbar that used Jerrold Starcom 7 cable boxes and Sony TVs. The Starcoms would put out a channel 3 that was a MHz or two low, and while the Sony TV would briefly settle on it, about once every fifteen seconds, it would rescan that range, probably looking for a better frequency match.


The other prospective problem is that if the leapfrog receiver output is not sufficiently precise, it might not be precise enough for the tuner in a digital TV, because I don't think that the digital TV tuners have anywhere near the "capture range" of the analog TV tuners. If I set an analog TV to "cable" and connect it to a broadcast TV antenna, it will find UHF 26 and call it Cable 77, and will call UHF 32, Cable 83, even though they are each two MHz off-frequency, but no TVs I have tested will lock onto a digital UHF broadcast frequency channel when the input channel plan of Cable TV has been selected, even if its tuner is capable of processing 8VSB when found on Cable TV frequency channels, as the current LG sets can. In other words, if I set an LG TV on cable in and connect it to a broadcast antenna and scan it, it will find no channels, but if I electronically shift one or more of the broadcast channels by 2 MHz to a cable channel, the LG will find it AND demodulate it, even though it is 8VSB rather than QAM, but most consumer TVs won't even do that.


At this point, we need to have someone with a leapfrog try it in this application.
 

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The LeapFrog (at least the one I found on Google) transmits on 2.4 GHz. It transmits composite video plus stereo audio. You need a corresponding LeapFrog receiver to pick up the signal. The output from the receiver is composite video, or alternatively to coax - but that's almost certainly the old channel 3/4 NTSC modulated video (though I cannot see a 3/4 selector switch).


I do not think you can attach a LeapFrog directly to an antenna. It needs a composite video source - like a DVD player or VHS machine.


I don't know of any consumer product that you can use like an ATSC broadcast repeater or channel-shifter.
 

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What about an old UHF converter from the 1960's. If tuned to the frequency of an ATSC UHF channel would it convert to the selected VHF channel as ATSC?

Another idea is a block cable converter from the 1980's. They took the entire cable band used at that time VHF, midband and a few channels above 13 and converted it to UHF.

Probably not, I wish I had kept some of these old things or I would try it out myself.
 

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Quote:
Originally Posted by Mister B /forum/post/16854804


What about an old UHF converter from the 1960's. If tuned to the frequency of an ATSC UHF channel would it convert to the selected VHF channel as ATSC?

Another idea is a block cable converter from the 1980's. They took the entire cable band used at that time VHF, midband and a few channels above 13 and converted it to UHF.

Probably not, I wish I had kept some of these old things or I would try it out myself.

They both have been tested to work by others here seveal years ago, but that doensnt address the original poster's need to transmit from one location to another.


I didn't realize that the leapfrog used A/V inputs rather than an RF tuner, so it would not work in this application.


As far as nybler's observation regarding the digital pilot carrier, that may cause a problem for converters in general, since it is not at the same frequency within the channel as the aural carrier, so it might move the channel a couple hundred KHz where the TV tuner might not recognize it.
 

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you could source the leapfrog with a dtv tuner (like a CECB) and watch that selected channel. you need to make a mechanism to change the channel on the dtv tuner. you could hack an rf or laser remote interface to change channels, if you used a CECB that had channel buttons on it then it could be done easier. you would need power and an enclosure with external antennas at the antenna.


the expense and complexity of the project is large.
 

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Welcome to the forum wiscsportsfan.


Using just the CECB to transmit the signal on RF 3 or 4 would work but it isn't legal and the FCC would be on your case if you caused interference.


Connecting the CECB to the Leapfrog, as previously mentioned, would work. It does have remote control extension but it isn't always 100 percent reliable. From Crutchfield review:
Quote:
Although the Leapfrog works great transmitting the DVR's remote signals into the other room, the remote has to be pretty close to the unit in order to get the signal sent, which for us means leaning forward from the bed to change channels, choose recorded shows, etc.

Other Crutchfield reviews:
http://www.crutchfield.com/p_209LF30...w&rvm=ShowAllt


Other devices, such as a wireless router or cordless phone, that also operate on 2.4 GHz might cause interference to the Leapfrog. Amazon reviews:
http://www.amazon.com/Terk-Technolog.../dp/B00009UHXR


You would need to have AC power for the CECB and the Leapfrog unless you run the CECB and Leapfrog on battery power.


What is keeping you from running a wire from the antenna to the TV?

Where are they located?
 

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Discussion Starter · #11 ·
First of all, thanks for all the replies.


Considering the fact that it sounds like an expensive project, it might be out the window for me. As far as my antenna, when it is in the attic the reception is beyond terrible. I built one of the antennas on the forums and the reception was really good, but it had to be close to a window. I have a problem though in the fact that I run a diplexer 100-150 feet away. My only option is to run the diplexer close to the tv where the antenna is. My cable signal is affected a great deal with it. I have to run two amplifiers to make the signal decent...


I wish I could wirelessly use the antenna signal to run the diplexer where it should be and my cable signal be a lot better.
 

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Quote:
Originally Posted by rabbit73 /forum/post/16855001



Using just the CECB to transmit the signal on RF 3 or 4 would work but it isn't legal and the FCC would be on your case if you caused interference.

Had a friend with in-house Cable service that wanted to watch TV on her back porch.


Picked off the channel 3 STB signal with a 2:1 splitter, built a low power class A amplifier (gain = 25 dB) and connected it to a dipole antenna.


Worked perfectly (only issue was that changing channels had to be done at the STB).


Walked her property with a hand held TV and found the range to be well within her property boundaries.
 

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Quote:
Originally Posted by MarioMania /forum/post/16864987


How do you build a low power class A amplifier?? and how far did it reach too

It's illegal, and could cause interference for others in your area.
 

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Quote:
Originally Posted by MarioMania /forum/post/16866666


I have a UHF transmitter that only reaches 4 houses down

And how did those four neighbors feel about it?



If one of my neighbors built a transmitter that interfered with my TV reception, I'd have a word with him about it. Hopefully that would resolve the issue without my having to complain to the FCC.


(This is for channels for which I am within the FCC's protected service contours, of course... I know that with the FCC's sanction of "white-space" devices the other channels are up for grabs.)
 

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Quote:
Originally Posted by MarioMania /forum/post/16866748


they have Pay TV anyways..I took off the antanna anyways so it's only reach the other TV in the other room

It can still interfere with others, even if a receivable signal is only in the same room.
 
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