Terrestrial antennas are cheaper than satellite ones and their configuration is not difficult to manipulate. It is enough to have a direct line of sight with the transmitting center, a high-quality TV signal amplifier and a good TV cable. On the territory of our country, the main channels of terrestrial television are easily received by such antennas.
Instructions
Step 1
Select the correct direction to the TV transmitting center and point the antenna at it. Aim over an antenna that has a narrower radiation pattern, i.e. on the UHF range, and choosing the weakest channel in it. Take the TV cable with the thickest center core. Connect to a level meter to a decimeter antenna and, while measuring the signal level, find its maximum: for MB1 (1-5 channel) - 74 dB, for MB2 (6-12 channel) - 60 dB, for UHF (21-69 channel) - 50 dB. If you don't have a meter, get a better picture. A defect in the image may occur due to insufficient signal level, then “snow” appears on the screen, or due to insufficiently high signal-to-noise ratio.
Step 2
Align the levels between the ranges. Unfortunately, this procedure is practically impossible to do without a measuring device. Traditionally, the first range is accepted quite strongly and often an attenuator should be introduced into the circuit. On the second band, channel 8 (Russia) has a powerful signal, and this usually requires the installation of a rejector on channel 8, it can even be adjustable. Using the same scheme, level the decimeter range using notch filters, in this case you may need a UHF preamplifier.
Step 3
After that, connect all cables with prepared bands to the multibend (multi-input amplifier), where the signals are summed, equalized and amplified using the range controls to the required level for feeding into the network. Keep in mind that the TV requires 60dB to 90dB, and a signal that is amplified over 100dB can create intermodulation (over-amplification). As a result, shadows appear in the picture when the picture of the second channel or "crosses" shines through through one channel. When the levels are lower, then you should change the antennas to more powerful ones or raise them higher.
