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Originally Posted by odog
I think I might be able to get these rabbit ears to work with some tweaking? I have them facing mostly west slightly south and actually right outside my bedroom window. I might be able to try to get them higher up as I have a little extra cable. Is there any other little tweaks that might work like adding something to the dipoles?
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That may be possible, though you may not care to keep the results indoors. Since Ch 4 is your only VHF station of any kind, your needs are simplified somewhat (other than the physical size required by this long wavelength).
The wavelength of Ch 4 is about 160". So, a half-wavelength dipole will need to be about 5% less than 80" wide, and even less with capacitance hats at the ends. So, your 36" is right in the ballpark. Fortunately, you have a moderate to strong signal, and your stations of interest form a fairly narrow grouping.
The gain and directivity of your dipole can be improved by adding director and reflector elements (collectively known as parasitic elements), turning your basic dipole into a classic Yagi-Uda antenna. The reflector is on the opposite side from the transmitter, about two tenths of a wavelength behind, and it is a bit longer than the dipole. In contrast, the director(s) are on the side towards the transmitter and are shorter than the dipole.
Also, you could start with an twinlead FM folded dipole antenna to form the Yagi driven element, or build it from wire or tubing. This requires a balun for attachment with the 75-Ohm coax cable. There are number of places describing the design and contruction of Yagi-Uda antennas on the Internet, such as these:
A cheap and easy TV antenna
Dimension_Table
http://www.k7mem.com/Electronic_Notebook/antennas/yagi_vhf.html
There are trade-offs to be made, so there are several strategies around for the exact size and arrangement of the parasitic elements. Roughly speaking, doubling the length of the Yagi boom will give almost 3
dB of extra gain. But, for your signal strength, you probably only need 3 or 4 elements (unless you suffer from multipath or other interference problems). Even if you build something else, you should be able to use your rabbit ears for experimentation. If you can find more rabbit ears or other bits of metal, they can serve as the reflector and director elements.
The few commercially available single-channel VHF Yagis tend to be a bit pricey. So, a combo VHF/UHF antenna will be more cost effective.
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If not, it looks like I'm needing a rooftop antenna possibly?
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Possibly. The single channel Yagi-Uda is a two dimensional array of wires, so it might be mounted along the surface a ceiling. This would require combining with a UHF antenna, possibly the one you already have, using a UVSJ (UHF/VHF Separator/Joiner) device, such as this:
Pico Macom UVSJ UHF VHF Band Separator/Combiner for Antenna (UVSJ) | UVSJ [Pico Macom]
The VHF/UHF combo antennas have UHF corner reflectors that stick out above and below the main boom, so they would have to go outside or in the attic. You have enough signal that you probably can get away with the attic mount, if that is feasible at your place.
As always, EV's suggestion of the CM 3016 (a VHF/UHF combo) for your TVFool data looks good. Here is a comparison chart of CM antennas:
Channel Master Antenna Reference Chart | Solid Signal
While looking for a VHF/UHF combo antenna, be sure to get one with adequate gain in the VHF-lo band. There are few of those stations remaining, so many antennas on the market are VHF-lo/UHF combos.
If you install outdoors, be sure to follow your local codes for mounting and grounding.
Good luck!