I have never been to this forum, and am at the very dawn of anything that could be considered knowledge of antennas. Up until this point in my life, I've never really thought much about it. I live near a fairly major metro area, and pretty much plug any old antenna in and it works (TV, radio). However, in the last year or so I for some reason or another I've started thinking about amateur radio, CB and antennas; the start of a hobby. But, that's a roundabout way of getting to my point.
On several sites (non-forum, instructional) I was reading about homemade FM antennas. I seldom listen to the radio at home, mostly CDs, and have not really had a need for "good" reception. On a whim, I decided to find out what would happen if I made an antenna from solely 16 ga speaker wire that I had an abundance of. Following instructions for a dipole antenna, I made the legs of a 'T' approximately 75 inches each (end to end 150 inches). This length came from doubling the minimum half-wave for 98 MHz and taking multiples thereof. Each leg is even, though a different instruction indicated to shorten one leg and lengthen the other to reduce interference in the transmission line. The transmission line (vertical leg of the T) is then selected as a multiple of the half wave length as well (but doesn't necessarily correspond to the horizontal length multiples). Now I think as far as construction, I should be good. Several sites gave conflicting means to determine half-wave length, that would result in differing by several inches one way or another. I chose one and stuck with it.
One common item throughout the various dipole antenna instructions was the 300 ohm twin lead wire for either using in the antenna part and/or the transmission line. I don't have any of that, and made the entire thing from the 16 ga speaker wire. I have a late 90's av/receiver that has a spring fitting for bare wire at 75 ohm unbalanced; the receiver does not have a 300 ohm balanced connection. I did some searching and understand the difference, but couldn't find any reason not to connect my new antenna to the only connection.
The result was it worked, extremely well, and in a basement setting (antenna elevation approximately 12" below grade). Not only that, but I barely cracked the volume and it was coming through loud and clear. With an auxiliary source volume would be 25% on the dial for the same decibel level. I decided to check the resistance of my antenna without knowing what it "should" be other than the labels of 75 unbalanced, 300 balanced, ... My reading was about 1 ohm.
If you're still here, my questions are:
1. Is there a danger of actually collecting too much RF energy with this setup connected to my receiver?
2. Could I make a variety of antennas typically using speaker wire? I really have way too much that I bought for a song many moons ago; it would be convenient to use it up.
A sincere thanks for any discussion provided. I feel certain these are basic questions or even nonsensical that probably aren't worth forum server space. However, after 24 hours of various internet searches, I am no more educated about the questions than when I started.
On several sites (non-forum, instructional) I was reading about homemade FM antennas. I seldom listen to the radio at home, mostly CDs, and have not really had a need for "good" reception. On a whim, I decided to find out what would happen if I made an antenna from solely 16 ga speaker wire that I had an abundance of. Following instructions for a dipole antenna, I made the legs of a 'T' approximately 75 inches each (end to end 150 inches). This length came from doubling the minimum half-wave for 98 MHz and taking multiples thereof. Each leg is even, though a different instruction indicated to shorten one leg and lengthen the other to reduce interference in the transmission line. The transmission line (vertical leg of the T) is then selected as a multiple of the half wave length as well (but doesn't necessarily correspond to the horizontal length multiples). Now I think as far as construction, I should be good. Several sites gave conflicting means to determine half-wave length, that would result in differing by several inches one way or another. I chose one and stuck with it.
One common item throughout the various dipole antenna instructions was the 300 ohm twin lead wire for either using in the antenna part and/or the transmission line. I don't have any of that, and made the entire thing from the 16 ga speaker wire. I have a late 90's av/receiver that has a spring fitting for bare wire at 75 ohm unbalanced; the receiver does not have a 300 ohm balanced connection. I did some searching and understand the difference, but couldn't find any reason not to connect my new antenna to the only connection.
The result was it worked, extremely well, and in a basement setting (antenna elevation approximately 12" below grade). Not only that, but I barely cracked the volume and it was coming through loud and clear. With an auxiliary source volume would be 25% on the dial for the same decibel level. I decided to check the resistance of my antenna without knowing what it "should" be other than the labels of 75 unbalanced, 300 balanced, ... My reading was about 1 ohm.
If you're still here, my questions are:
1. Is there a danger of actually collecting too much RF energy with this setup connected to my receiver?
2. Could I make a variety of antennas typically using speaker wire? I really have way too much that I bought for a song many moons ago; it would be convenient to use it up.
A sincere thanks for any discussion provided. I feel certain these are basic questions or even nonsensical that probably aren't worth forum server space. However, after 24 hours of various internet searches, I am no more educated about the questions than when I started.