Hi All!
I made a quick prototype of a fractal type antenna to receive digital broadcast television form one of many designs found on line & in text books. I am curious about the wiring:
In all of the designs I viewed, one of the lead wires is connected to the center wire of the coaxial cable and the other is connected to the shield. (With or without passing through a balun, depending on the particular author's description.)
The left column of the attached photo (of a really quick prototype) is attached to the center wire and the right to the shield.
I took apart a television and saw that the shield connector is connected to the case of the tuner.
The Main Question-
I am wondering if the right column (attached to the shield) is actually doing any work receiving broadcast signals, or if I would have even better reception if the two columns were connected together to the center coax wire so both columns capture signals. The coax's shield would then be simply dead ended.
A Balun Question-
I think I still remember the purpose of a balun from the olden days of parallel cable lead in wires. As I remember, hopefully correctly- if not balanced, one of the conductors will radiate signal away from the receiving components, hence the need for a 75-300 ohm balun.
In some of the homemade designs, a balun is used to connect coaxial cable to the lead wires on the antenna. In this one, I tried with and without the balun. In each, I received the same channels and the same signal strength bar rating on the weaker stations. (Actually lots more stations than I expected.)
Is a balun actually helpful in such a short lead wire setup?
Thanks Very Much for explaining & educating! It's always good to learn & understand new things.
Enjoy This Day!
Paul
I made a quick prototype of a fractal type antenna to receive digital broadcast television form one of many designs found on line & in text books. I am curious about the wiring:
In all of the designs I viewed, one of the lead wires is connected to the center wire of the coaxial cable and the other is connected to the shield. (With or without passing through a balun, depending on the particular author's description.)
The left column of the attached photo (of a really quick prototype) is attached to the center wire and the right to the shield.
I took apart a television and saw that the shield connector is connected to the case of the tuner.
The Main Question-
I am wondering if the right column (attached to the shield) is actually doing any work receiving broadcast signals, or if I would have even better reception if the two columns were connected together to the center coax wire so both columns capture signals. The coax's shield would then be simply dead ended.
A Balun Question-
I think I still remember the purpose of a balun from the olden days of parallel cable lead in wires. As I remember, hopefully correctly- if not balanced, one of the conductors will radiate signal away from the receiving components, hence the need for a 75-300 ohm balun.
In some of the homemade designs, a balun is used to connect coaxial cable to the lead wires on the antenna. In this one, I tried with and without the balun. In each, I received the same channels and the same signal strength bar rating on the weaker stations. (Actually lots more stations than I expected.)
Is a balun actually helpful in such a short lead wire setup?
Thanks Very Much for explaining & educating! It's always good to learn & understand new things.
Enjoy This Day!
Paul
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