TV aerial gizmo

If I understand your question correctly, the answer is "no". What you're wanting to do is to rebroadcast the RF ssignal from your TV antenna. Not a good idea, since the retransmitted signal would severely intefere with the real broadcast signal, killing all reception. What you need is a transmitter/receiver pair that translates the signal to a much higher frequency than the TV signals. This avoids any interference with the original broadcast signals. However, this approach requires that you have a set-top box to convert the broadcast signals to video and audio, retransmit them to a receiver at each TV set, where the video & audio are demodulated and sent into the TVs. Look at the description at

to get more details. Google for "wireless digital tv transmitter" and see the products available. Read their capabilities carefully.

The best approach would be to connect your TV antenna to a distribution amplifier, then run coax cables (RG-59) to all the TVs in your house. A very good distribution amp is at

(CM3414)&c=Amplifiers&sku=. It works quite well in just about any environment, is very low noise, and has connections for up to four TVs and a cable modem for your computer. Avoid the cheapie amps such as you would get from Walmart.

--
David
dgminala at mediacombb dot net

Well, yeah, sort-of, but it's a bad idea.

In order to do this, you'd need a broadband amplifier, and an indoor antenna which would retransmit the whole TV spectrum.

The problem with this approach is that if you amplify the signal from the aerial enough to reach the bedroom TVs with a useful strength, there's a *very* good chance that it would be strong enough to reach back up to the aeriel and be picked up again (mixing with the incoming signal from the TV transmitters). At best, this would cause image degradation and "ghosts" (if analog) or a higher bit-error rate with video dropouts (if digital). If worse, it would create a horrendous RF feedback problem which would obliterate television reception throughout your house, and possibly affect nearby houses as well.

It's sort of the radio-frequency equivalent of using a PA system, with the microphone too close to one of the speakers... it lets out a terrible "howl" of feedback. This is not what you want.

Also, it's probably illegal to do this in your jurisdiction, since you would in effect be creating an unlicensed over-the-air television transmission system.

You're much better off using a "wired" signal distribution system... typically, with 75-ohm coaxial cable... and running a coax to each individual television set. You would need a signal splitter (passive), or a powered "distribution amplifier" if your aerial signal isn't strong enough.

You can (in almost all cases) disconnect the set-top aerial, and connect the coax to the TV instead (some have 75-ohm coax inputs, and others have a pair of screw terminals for a 300-ohm connection - you would need a 75-to-300-ohm "balun" to make the connection).

--
Dave Platt                                    AE6EO
Friends of Jade Warrior home page:  http://www.radagast.org/jade-warrior
  I do _not_ wish to receive unsolicited commercial email, and I will
     boycott any company which has the gall to send me such ads!

Sure! It is called a splitter.

Insert it between your antenna and your living room TV and run coax from it's other outputs to the cable inputs of your other TVs.

--Winston

If you find running coax through your house unappealing enough that you would settle for selecting a program in your living room and watching it in another room, or rooms, a few companies sell a 2.4GHz link for that purpose.

Winston wrote in :

Although if yer in a weak reception area, you may need an amplifier. Splitting the signal makes it weaker for all the TVs.

Growing up, we wired each room for TV. Since we were in a remote area, we only got three channels, and all of them were weak.

We had a huge TV antenna on a 100' crank-up tower (75' of tower, 25' of drilling rig pipe at the top), with a pre-amp at the antenna (voltage to run it was injected into the coax leading to the antenna by the distribution amp), and a distribution amp down at the living room TV, where all the other TVs were fed from.

Even with all that, we still had to rotate the antenna to get a better signal. My dad bought a surplus prop-pitch motor off a WWII airplane, wired it up so it could be controlled from the living room, lowered the tower, tilted it over, mounted the prop-pitch motor, and it worked a treat.

Then we got satellite... a big 10' dish.

It's so much easier nowadays. .

A friend of my grandparents lived in Kitchener, Ontario. The first TV signals in their area came from Buffalo, New York, but he was eager to see the modern miracle. I forget the height of the tower he put in his backyard -- it was still there when we visited them in my youth -- but if memory serves it was fifty feet high.

You should have lived in the central US. Friends who farmed out by Peoria needed only a six-foot dish, mounted on the ground. When they wanted to change satellites they just walked outside and handcranked it.

ial

to

I lved in Florida on the east coast, Fort Pierce. Worked in a tv store summers home from college. In 1953, tv transmitters were only in Miami and Jacksonville, 135 and 225 miles away. We used crank-up and tilt-over towers 40' tall to get Miami, with vacuum tube preamps on the towers and 300 ohm twinlead to the sets. When lightning hit, as it frequently did, we got fried tuners and amplifiers and melted downlead. We could only work on antennas in the mornings due to lightning danger from noon onwatrds. When West Palm Beach got tv, it was great, only 50 miles to the nearest station, we didn't have to use amplifiers on the 40' towers.

snipped-for-privacy@att.net wrote in :

erial

t to

My dad was a big believer in proper grounding.

We had a half-mile long-wire antenna that seemed to drain off most static buildup before it got to the point of a lightning strike. On each pole supporting the long-wire antenna, there were big lightning rods that we took great pains to sharpen to a needle-point. These ran into 6' x 6' x 1" copper plates, buried 10 feet in the ground at the base of each pole. I think he got the copper plates from military surplus.

The long wire antenna was almost always charged with static... there were times when it would jump a 12" spark during heavy snow storms or high winds. We kept it grounded to the same ground as the TV antenna tower was grounded to, except when Dad was using it to transmit, or we lost power, then we hooked up a 40 watt fluorescent light to it so we could see.

The TV antenna tower also had lightning rods spaced at 25 feet intervals up its height, grounded through a braided copper line about half the size of my arm that was buried 10 feet down around the perimeter of the house then run to a 10' x 10' x 1" copper plate buried 20 feet in the ground, right above the water table.

The lightning rods on the roof (spaced every 10 feet, along the peak of the roof, and along the perimeter, along with 4 lightning rods on the chimney) also went into that same ground.

We had quite a few direct hits... never blew out any electronics, though.

(...)

But if yer in a strong reception area, you've solved the problem for ~$20. If signal strength is insufficient, yer money's not wasted because you can insert yer distribution amp between the antenna and the input of the splitter.

(...)

And watching the shows from 'way back is pretty painful now because most of the magic was in the experience of watching a real television rather than the quality of the production.

:)

--Winston

It's called "twinlead" or "coax".

Buy a splitter and some cable.