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Ferrite vs wire antenna for MW

Pjdd

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Assuming that each is reasonably matched to a receiver input, which is likely to be more sensitive for the 0.5 - 1.6 MHz band - a 1x10 cm ferrite antenna or an outdoor 30-ft wire with a 15-ft downlead? To be more specific, say the ferrite antenna is to be used inside a wooden house without massive wiring on the walls. Is one a clear no-contest "winner" over the other or does it depend on other factors?
 

BradtheRad

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The commercial AM band. For long wavelengths it's better (theoretically) to have a longer antenna high in the air as is practical.

But then thinking back to my boyhood (living in Phila. in the 1960's)...
It's remarkable that my little pocket transistor radio was able to bring in 'superstations' such as:
WABC New York
WKBW Boston
WLS Chicago

The antenna was just a ferrite 2 or 3 inches long.
Darkness assisted radio broadcasts to bounce off the ionosphere of course.

Over the years light dimmers and computerized appliances have created more noise on the AM band. Better reception might come from whichever antenna which is far from a house.
 

betwixt

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I used to listen to New York and Boston stations here in the UK years ago, before the noise pollution became to great. That was on a long wire antenna.

An outdoor antenna will undoubtedly work better but a Ferrite rod has the advantage of being easy to rotate, both are directional and in some instances it may be better to null out interference than peak the desired signal.

Brian.
 

Pjdd

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I'm thinking more about efficiency in collecting RF energy than with selective pick up of distant stations. For example, there's a 540 kHz AM station about 1.5km from my house. The Tx antenna is in LoS except for the trees near my house. I was wondering which antenna will collect the strongest signal from that station.
 

betwixt

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The wire will win easily but if this is an energy harvesting experiment you should be aware that a few microwatts of power is all you are likely to get.

Brian.
 

Pjdd

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I see that my wording could have been misleading. It's not about harvesting free power for application to something else. Allow me to explain further.

Some 40-50 years ago, I designed and built several receivers fixed-tuned to the local station and gave them away to friends. No two designs were the same. Some were basically crystal receivers with the output to be fed to an existing amplifier. Others had a single-stage rf amplifier with AGC and an audio amp. Even the crystal receivers worked fine with a 1-foot antenna when fed to a ceramic pick-up phonograph amp. Now I'm wondering, with better optimization of the design, how powerful a reception I can get before or without amplification.
 

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All evidence favors the long wire antenna. I suppose we would say the longer the better...
And then I wonder if we should add, within reason? Because I'm starting to wonder about the effect of, say, 10 photons on a larger antenna, versus a smaller antenna. Shouldn't we expect the larger antenna to generate less voltage amplitude, due to having greater number of atoms, or greater electrical inertia, or greater inductance?
 

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