Per HDTVPrimer website model, Silver Sensor has Raw Gain ~ 7 dBi
across entire UHF Band....which is more than a 2-Bay Bowtie (e.g. Mohu Leaf, WallTenna) and much more than a simple Loop used with most Rabbit-Ear Antennas. If you look at the detailed Azimuthal Pattern chart for the Silver Sensor, you'll also see that it has a very broad Beamwidth with significant suppression of Multipath coming in from the rear:
For more Gain, you're gonna need a bigger Boat....err Antenna.....
However, a higher Gain Antenna also means a narrower Beamwidth, which means it will have to be more carefully pointed toward signal sources. Perhaps located in the top of a convenient closet....
FF4, Free-Form 4-Bay Bowtie provides UHF Raw Gain = 9.7 to 12.6 dBi
in a simple DIY project that can be as easy as AWG10 wire or even metallic or aluminized tape on Cardboard (perhaps hidden behind a Picture if the direction to stations permits). It also provides Hi-VHF Raw Gain = 3.5 dBi
, with only a slightly higher than desirable SWR:
If you have room for it, adding a Reflector to the FF4 can increase Gain by about 3 dB, with much more suppression of Multipath from the rear. The only Reflector I've modeled for the FF4 is a HUGE Double Angled Reflector:
For a "flatter" FF4, you might want to consider using a 36"Hx36"W FLAT Reflector 5.5-inches away from the Bowties, made from either a piece of Cardboard covered in Aluminum Foil or METAL "Mesh Hardware Cloth" which should be available in your local hardware store, such as:
UHF Quad Trapezoid Loop with 15 Reflector Rods
provides UHF Raw Gain = 10.1 to 11.8
. [Without RR's Gain isn't much higher than Silver Sensor.] This SIMPLE DIY project is useful when the station directions make it difficult to mount the antenna on a wall, since it has a very wide Beamwidth of 60+ degrees all across the UHF Band. It also provide Hi-VHF Raw Gain ~ 6 dBi
, but with excessive SWR that may *or may not) limit it's usefulness to strong local signals. Instead of 15 Reflector Rods (RR), you could use the same overall size Alum. Foil or Metal Mesh Hardware Cloth: