Wanted: Killer Indoor FM Antenna

We bought one from a forum sponsor here at AK. Works fine.

Omegaman said:

I read somewhere on the innerwebs that an antenna folded into a FRACTAL pattern increased reception

search for "Fractal antenna design"

Is there some need for a ground also, to be safe maybe?

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Thanx for the suggestion. I did a quick search for "Fractal Antenna" and it brought up some interesting reading. I'll look into it further. My tuner does have an HD band.

I have done a fair amount of research, software modeling, design and measurement of fractal antennas.

Not all of the information on the internet is correct.

Below is the result of one of my efforts. The name rabbit ear fractal antenna is just a little funny thing. I was posting the results of some of my efforts on AK in an antenna thread and someone mentioned rabbit ear antenna.

If you look at the diagram of the antenna, it somewhat resembles a stylized rabbit. The elements that make of the eyes, the nose and the mouth do not really contribute much to the operation of the antenna. Again just a little funny thing.

However the measured performance and the software modeled performance are true.

I used 4nec2 as the antenna modeling software.

An antenna with gain on the FM broadcast band is not going to be a small antenna.

In general a fractal antenna can provide a wider bandwidth and either a smaller antenna for the same gain or a little bit of gain in a full size antenna.

The so called star type fractal antennas, which one will find on the internet, perform more as what is called a meandering wire antenna than a true fractal antenna.

I spent some time designing, software modeling, building and measuring some designs and posted the results in other threads on AK, but there seemed to be little interest, so I stopped.

One style of antenna that may provide some advantages is the Hoverman or Gray-Hoverman style antenna. They are not small antennas, but the elements are in a single plane and the antenna could be hung a wall facing the station(s) of interest.

Most of the designs as found on the internet are for the UHF TV band with a few that will work somewhat okay down into the VHF TV Band but all most all of them are very poor at FM broadcast band frequencies.

BTW, for those of you that take a close look at the picture you will note that in the comment section, I list 300 Ohms as the feed point impedance, I changed to 75 Ohms but neglected to change the comment section.

In terms of " My tuner does have an HD band.", it is the same frequency range as standard FM broadcast band signals. Advertizements that say an antenna is digital ready are just using so much jargon.

An RF signal is an RF signal and the antenna does not care if the signal is analog or some form of digital modulation.

All the antenna cares about is the actual RF frequency of the signal and direction if the antenna is a directional antenna.

Gfedery I put on my rabbit ears So far THAT has made a noticeable improvement. made a 90 degree bend, and set each arm @ 26"

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For simple a antenna it is hard the beat the good old rabbit ear style antenna. Of course it is just a rigid dipole antenna.

Make the elements longer for stations at the bottom of the FM broadcast band and shorter for stations at the top of the FM broadcast band.

Starting at about 32 inches at the low end of the band to about 26 inches at the high end of the band for each antenna element in general round numbers.

Experimentation with the length and the angle formed by the elements is your friend.

JBL GUY said:

There is no substitute for full size resonant frequency antennas.

When it comes to RF signal reception it is location, location, location.

A particular recommendation for a particular antenna does not mean a lot, unless the actual RF field strength that the antenna sees is specified.

This BIC BeamBox antenna is less than a full sized antenna and is not as sensitive as a full sized antenna. Its claim to fame is that it is electrically directional and one version has a not real narrow, adjustable passive band pass filter.

They may work okay in areas of moderate to strong RF field strength for the station(s) of interest.

One thing to remember, most of the population of the US lives in areas of moderate to strong RF field strength for local FM broadcast band stations.


In general, the better the performance of a tuner or receiver, the less an amplified or powered antenna will help, unless the amplification is used to overcome feed line and splitter loss.

Did your Terk antenna work okay for you? If so you could just replace it.

Or are you looking for something that works better than the Terk antenna?

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I agree, no substitute for a full size antenna.
Omni's are good, directionals even better with a rotor.
most indoor antenna's have at the most the same gain as a folded dipole antenna.
In one set up I had 2 of these on opposite walls and switched between them depending on the station location.
As mentioned rabbit ears work fine in some locations-just as good as a Terk.
I currently use on of the a half wave Omni that is basically two car antennas on top of each other-mounted outside.
It would work inside as well.
You would be surprised how much better the work outside vs inside if you can manage it.