Indoor antenna for FM radio
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Take a 1.5 Meter long peice of Coax cable with an F connector on one end and strip ~1meter of the outer layer and sheilding off leaving the white insulator and core wire. Screw the F connector onto the AVR's FM ant jack and raise the rest of the cable up and attach the end to a wall with tape or a tack, finish nail etc. You can even let it hang down if it works there also.
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I would like to know the result too.
I would like to know the result too.
I've used a variety of antennas of this variety and they generally work far better than Rabbit ears, if for no other reason due to the probability that they will be located more advantageously. Most FM modern FM tuners have very sensitive front ends that come within a few dB of theoretical maximum possible performance. That means that any further gains will come from improved antennas. A simple antenna that is raised up above local disturbances to the RF field can provide stunning performance.
Active amplification of antennas only makes real sense if the amplification serves to overcome losses in the signal distribution system. Therefore a single antenna driving a single receiver over a low loss line will show minimal actual improvement in performance with the addition of an amplifier.
I've used a variety of antennas of this variety and they generally work far better than Rabbit ears, if for no other reason due to the probability that they will be located more advantageously. Most FM modern FM tuners have very sensitive front ends that come within a few dB of theoretical maximum possible performance. That means that any further gains will come from improved antennas. A simple antenna that is raised up above local disturbances to the RF field can provide stunning performance.
Active amplification of antennas only makes real sense if the amplification serves to overcome losses in the signal distribution system. Therefore a single antenna driving a single receiver over a low loss line will show minimal actual improvement in performance with the addition of an amplifier.
The length of the antennae is determined by the frequency you are trying to tune and since the FM band of broadcast Radio ranges from 88MHz to 108Mhz the wavelength ranges from 3.41 m - 2.78 m. So you cut the unsheilded portion of the cable to the middle of the range of wavelengths you are trying to tune which is 3.1 meters.
And yes it works better than rabbit ears which are designed to tune in different wavelengths.
Edit: Having the 1st half meter of cable sheilded just gets the antennae away from the other electronics. Most antennaes that come with AVRs desktop radios don't even do this and they work well.
Edit 2: 3.1m is a full wave antennae. 1/2wave = 1.55m and 1/4wave = 0.775m so choose any one of these 3 lengths.
Just for fun I measred the little antennae that came with the new Pioneer receiver and it measured 58inches and has a piece of plastic with a hole in it at the end of the wire to mount it on the wall with a tack or nail.
And yes it works better than rabbit ears which are designed to tune in different wavelengths.
Edit: Having the 1st half meter of cable sheilded just gets the antennae away from the other electronics. Most antennaes that come with AVRs desktop radios don't even do this and they work well.
Edit 2: 3.1m is a full wave antennae. 1/2wave = 1.55m and 1/4wave = 0.775m so choose any one of these 3 lengths.
Just for fun I measred the little antennae that came with the new Pioneer receiver and it measured 58inches and has a piece of plastic with a hole in it at the end of the wire to mount it on the wall with a tack or nail.
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Does the reduction of length result in reduction of signal reception?
Yes it does but the 1/2 wave 5ft antennae is just fine. Heck, mine is draped over a chair.
Edit: I was googling for a quick explanation and everything I found was about transmitting over antennaes but your antennae needs to be "tuned" to the wavelength of the frequency you wish to receive. Either full wave, 1/2 wave or 1/4 wave. Anything else will still work just not as well. If you have room for a 10ft full wave then go for it otherwise the 5 footer is what comes with receivers. The wall of your house will reduce the reception (gain) of the antennae by about 6dB. A window will only reduce the reception by 3dB so just having the antennae outside is a big improvement. Unless you live far away from town the 5 ft should work well.
Edit: I was googling for a quick explanation and everything I found was about transmitting over antennaes but your antennae needs to be "tuned" to the wavelength of the frequency you wish to receive. Either full wave, 1/2 wave or 1/4 wave. Anything else will still work just not as well. If you have room for a 10ft full wave then go for it otherwise the 5 footer is what comes with receivers. The wall of your house will reduce the reception (gain) of the antennae by about 6dB. A window will only reduce the reception by 3dB so just having the antennae outside is a big improvement. Unless you live far away from town the 5 ft should work well.
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Incorrect...
The FM tuner circuit within present day AVRs delivers worst RF performance compared to previous tuners. Today an integrated circuit handles the majority of tuner functions that includes a digital synthesizer front end for tuning and presets, unfortunately its actual performance for sensitivity and selectivity is not very good. The audio brands can get away with this marginal performance as the tuner specs ranks low on the consumer's preferences, plus 80% of the AVR users are located in/or near a major city so the FM station's signal strength is adequate. This is easily confirmed by comparing present day electronic digital tuner specs versus those of a good analog tuner especially one with a multi-gang tuner, starting with 50dB stereo quieting...
Just my $0.05... 👍😉
Incorrect...
The FM tuner circuit within present day AVRs delivers worst RF performance compared to previous tuners. Today an integrated circuit handles the majority of tuner functions that includes a digital synthesizer front end for tuning and presets, unfortunately its actual performance for sensitivity and selectivity is not very good. The audio brands can get away with this marginal performance as the tuner specs ranks low on the consumer's preferences, plus 80% of the AVR users are located in/or near a major city so the FM station's signal strength is adequate. This is easily confirmed by comparing present day electronic digital tuner specs versus those of a good analog tuner especially one with a multi-gang tuner, starting with 50dB stereo quieting...
Just my $0.05... 👍😉
Forgot to add that an F to RCA connector and an RCA patch cord ( 6ft cut to 60 inches or 3ft cut to 30 inches) will make a good antennnae if you don't feel like cutting up an old cheapie RG59 coax cable that used to come with VCRs or whatever. Just about any wire, it's the length that's important.
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