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can you use a fractal antenna on a older tv (Tube tv) or does it work only on hdtv? Answered

Hi  there
Can a fractal antenna work on a ordinary TV  or do you need to use a HDTV 




7 years ago

All antennas do the same thing. When transmitting they excite magnetic vibrations given electric energy. When receiving they do the reverse. Neither the magnetic waves nor the electrons care in the least what type of information they carry. All that counts is the frequency and strength of signal.

The single proviso with respect to information is that higher frequencies can pack in more information than lower ones. You can do Morse code at audio frequencies but that isn't much. Video is a LOT of information and so is only practical at VHF and up (unless you don't mind waiting several minutes for one still frame).

Other than that, it doesn't matter. So if a TV station is still broadcasting on channel 3 in the VHF or on channel 53 in the UHF then it has not changed its transmission frequency and the same antenna will work now as worked before with one small consideration. Digital signals will be packing more information. So if you had a slightly snowy picture before with a given antenna you may get nothing now due to the same level of loss being now more significant. You may now need additional gain to compensate for those losses. Let me explain at some length.

Frequency determines antenna size. The higher the frequency the smaller an antenna's elements can be. The smaller those elements can be the more complex and elaborate you can make it for the sake of increasing gain. By gain is meant how directional it is.

In short, any kind of antenna can be used for any kind of signal. The weaker that signal the more gain you require to be able to capture it clearly. The further away the signal source the higher the receiving antenna has to be because of how the earth curves. So the limitation is how big an antenna it is practical to make for a given frequency and for how high above the ground it must be. A huge dish antenna at the top of a big tower would be blown down by the wind.

Other extremely high gain antennas would be difficult to point because blowing wind would make them flutter. Think of trying to view an object with a high power telescope and how still you need to hold it.

Also there are losses in the lead wire. The higher the frequency the greater those losses because effective length is measure in wave lengths. Lower frequencies have longer wave lengths, higher ones shorter. Think of a tall person taking his longest step versus a short person. Like that.

So it is only a trade off of practical factors, not of the "information" that signal contains.

Paging through my copy of the Antenna Engineering Handbook I have lately been thinking to try and build a directional 3-element, terminated rhombic for 2.4 GHz for my XBee modules.

Sorry if I've been too verbose.



8 years ago

The TVs are receiving signals in the same sort of frequency-range. A good aerial for either will be better tuned, but you should still be able to do this no problem.
The other half of the receiver is in the TV, so the aerial isn't everything.



8 years ago

.  A lot depends on the quality of the antenna (some HDTV antennae are designed more for looks than performance) but it should work well - at least on the UHF channels.


8 years ago

If it works with an hdtv then it works with a tube tv.  The tube tv will still have to have a converter box and the converter box is what receives the signal from the antenna.  The box then converts that signal to something that the older tv's can use.