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Go to the link below,
Fill out the location information (that won't be shown for public view)
Scroll down to the bottom of that page, and enter the height that the Antenna will be placed.
When the Analysis Page is shown, copy the bold address line shown near the top of the page,
and paste that into your reply here.
Once we have that, and look at the information, we can continue this discussion.
In Myrtle Beach there are multiple signals coming from multiple directions. I did check and saw that there are both high VHF signals and UHF signals. The best type of antenna will be dependent on your location and what stations you want to receive. So please post the URL to the radar plot for your TVfool report.
I agree with the suggested Stellar Labs 30-2440. At first glance at the TV Fool report antenna aiming to receive all major networks would seem to be a difficult choice with so many good signals coming from different directions. After looking up WMBF and finding that it is an NBC affiliate. I would suggest to try aiming at 347 degrees. Keep in mind a small dual band antenna like the 30-2440 will have some reception off the back and sides. As with all antennas, and locations you will need to experiment with aiming, and placement of the antenna. You really are not going to know until you try. With a TV Fool report that looks as good as yours does with some time, money, and experimentation you could probably put together an antenna system to receive everything on your report down to WITV providing you don't have excessive nearby blockage.
Stay away from the ebay antenna you linked to. Even when they do work it's often for a very short period of time. The built in rotor often fails within days and has no way to indicate which way the antenna is pointing. The cheap amplifier will overload in strong signal areas, and there is no way to bypass it. When placed outside they fall apart in few months time.
If you wish to continue looking at other antennas I can certainly offer advice on other antennas I would consider for your area. Some signals in your area are predicted to be very strong the use of anything amplified is very likely to overload. You need an antenna with high VHF/UHF capabilities. Your signals are strong enough that you don't need a real monster of an antenna. With that in mind the other antennas I would consider for your area are.
The Winegard HD7694P which would probably be my first choice if I wasn't so cheap.
The next one that comes to mind is the RCA ANT751 while I feel it can be a bit lacking in UHF performance it is a very good little antenna for areas with good strong line of sight signals, and no nearby blockage.
The other one that comes to mind is the Antennas Direct ClearStream 2V. A very good UHF antenna with some high VHF capability added on for use in areas with strong high VHF signals. Some of the VHF signals that should be easy to receive in your area are from over 50 miles away. What I see when I look at a C2V is a UHF double loop driven element, a UHF reflector, and a pair of rabbitears added on for VHF.
Where does the Stellar Labs 30-2440 fit into all of this. First the price is good. The reviews, I read on this forum, other forums and sales sites have been good. The Stellar Labs 30-2440 uses a compromise dual band driven element and some added VHF reflectors. The gain claims for the Stellar Labs antennas are a bit questionable, but become a bit less so when you look at the design frequencies which possibly have peak gain occurring outside the current US broadcast television bands, should still work quite well in this country. What I see when I look at the 30-2440 is a compromise dual band UHF/VHF driven element, a set of UHF corner reflectors, a tri-boom set of UHF directors, and a pair of VHF reflectors. An Asian copy of an older European Televes design.
With the loss of Antennacraft there are not a lot of good choices left in the U.S. market place. While to the best of my knowledge Winegard antennas are still U.S. made. It's gotten hard to avoid using imported antennas. To the best of my knowledge the RCA ANT751 is built by Winegard.
Stay away from amplified antennas - you have several strong stations and amplifiers may overload your tuner. You can always add one later IF NEEDED. And let me repeat what's been said: stay away from the antenna listed on eBay and others like it. Claims of reception from over 100 miles are outright lies - the curvature of the Earth limits reliable reception to about 80 miles or so. If it seems too good to be tru, it probably is.