Hello! After getting into "better than most consumer grade audio" audio about a year ago, I have today wanted to listen to some FM radio on a receiver I have. Now for all of my life using FM I had just used the single wire attached to a high place going to your adverage consumer garbage stereo, but I find this receiver I have is much more complicated.
There is connections for 300 and 75 ohm FM antennas, and I don't know what to do with either of them. I don't have special wire, just normal wire, what can I do to get some radio playing?
There is connections for 300 and 75 ohm FM antennas, and I don't know what to do with either of them. I don't have special wire, just normal wire, what can I do to get some radio playing?
Ummm, I don't currently have any sort of antenna, just wire, and I'm not really sure what to do with it.
Can you explain more about this T thing?
Using twin core speaker wire, tear one end apart to make a "T" shape.
The width of the "T" needs to be approximately (300 000 000 / f / 4) metres. Where f is the frequency in Hz of the staion you are trying to receive.
The two wires that are still adjacent to each other are connected to the 300R aerial input.
The width of the "T" needs to be approximately (300 000 000 / f / 4) metres. Where f is the frequency in Hz of the staion you are trying to receive.
The two wires that are still adjacent to each other are connected to the 300R aerial input.
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I want to receive a wide range of frequencies.
I don't understand why I have to do all of this if a normal consumer grade stereo requires just me placing one wire in a suitable spot to get all of the stations.
Well I just made one of those with maybe 6 foot on each end of the T and it is barely giving me anything more than static on any station.
Hi-End receivers are often less sensitive than cheapie ones, they rely on a higher signal strength at the input to reduce FM noise.
Your T aerial will be directional so you will need to turn it round so that it is perpendicular to the transmitter. (ie if you were holding it, you are facing the transmitter).
If the arms of the T are too long or two short it will not be tuned to the station that you are trying to receive. For 90MHz each arm should be about 33 inches.
Your T aerial will be directional so you will need to turn it round so that it is perpendicular to the transmitter. (ie if you were holding it, you are facing the transmitter).
If the arms of the T are too long or two short it will not be tuned to the station that you are trying to receive. For 90MHz each arm should be about 33 inches.
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Facing the transmitter! Oh god this is getting really picky now, I don't even know where some of these stations are in respect to me.
And the thing is, this is facing one of the transmitters now, and I'm getting a garbage signal.
So I guess every time I buy a receiver with a built in tuner I could just forget about it.......
Take about 6' of wire, shove it into the center terminal of the 75 Ohm coax input on the receiver, tape it to the wall, and see what happens. Or go to Radio Shack and buy a set of 'rabbit ears' like >>AXIS 10-8120/41704 Indoor Antenna; Model: PET10-8120 Catalog #: 55068910; $5.99<< and see where that gets you.
My 75 ohm hookup are the little things like on speaker jack hookups. I put a wire in there and it did about the same as that dipole T thing on 300Ohm, which is not much.
I"ll check out some more stuff online for homemade stuff and maybe get that radio shack antenna you recommended.
No, you just really need a REAL antenna. Using a piece of wire is kinda a hit or miss proposition. Go down to a good electronics(Hi-fi shop) store & ask for a 300 Ohm Ribbon Dipole antenna. They are just a carefully crafted, specific (piece of wire) that is tuned to pick-up FM stations. They are rather cheap, call around. I think when you get the thing you'll get all the stations you want. Question: Do you get acceptable reception on your car FM radio while parked close to your home? If so, you should get identical or better reception with this 'ribbon' antenna on your home tuner. Simply tape it to the wall behind your tuner, hide it behind something perhaps, the antenna won't "see" that it's behind anything. Arrange this antenna as a big "T" on the wall, it may be that you don't need it "up" the wall, often down just a few inches above your tuner but "spread out" as the "T".
## Radio Shack ## No. 42-2385 ## $8.99 Dipole antenna ##
______________________________________________Rick.............
## Radio Shack ## No. 42-2385 ## $8.99 Dipole antenna ##
______________________________________________Rick.............
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I just don't see whats so different between my wire and this other wire (I have seen I t and I know what wire your talking about specifically). Perhaps I'll buy some and make a dipole.
And yes, a car, and even a car radio I had inside my house, with JUST a 1 foot long piece of wire for an antenna, got pretty good reception.
What's the difference?........A lot, trust me a WHOLE lot.
Think about what this little piece of wire is trying to do...It's trying to "capture" electromagnetic radiation flying thru the air & covert it into some useful amounts of voltage to be "descrambled" thru your tuner into an audio signal. If your interested, look up "Transmission Line Theory" Heavy stuff it is.
___________________________________________________Rick................
Think about what this little piece of wire is trying to do...It's trying to "capture" electromagnetic radiation flying thru the air & covert it into some useful amounts of voltage to be "descrambled" thru your tuner into an audio signal. If your interested, look up "Transmission Line Theory" Heavy stuff it is.
___________________________________________________Rick................
I know a fair bit about electronics and electrical and I can tell you, copper is copper. The only differences are insulation, spacing, capacitance, conductance, inductance, and resistance, so it must be one of those.
I can appreciate the shape of what you make with the wire affecting the signal but you can't tell me that the wire is somehow different without at least giving an explanation of in what way it is different.
I know impedance is a big problem, I've got a few ohms, not 75 or 300, however I've taken a roughly 10FT long piece of wire and put it in the 75ohm connection with a 1k resistor in series and I can pick up one station pretty clearly however the volume is very low and it is actually clearer on a frequency that is near but not exactly the stations broadcasting frequency.
I have no idea how my local stations are polarized.
And after you get a perfect antenna with perfect reception, you'll hear the dreadful processing your stations do to the signal. You folks complain about loudness wars on the CDs but that's nothing compared to what the radio stations do to the audio.
Many years ago a friend told me about a pirate station in my neighborhood. The operator connected his CD player to the transmitter with no processing. He obviously knew how to set it up because that was the best sound I ever got out of that H-K Citation 15 tuner. The programming was eclectic and very enjoyable. I still have the tuner. I wish I still had the pirate.
G²
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