Sunday, October 23, 2011

UHF TV booster preamplifier with a transistor

Booster, preamplifier or signal boosters, maybe people have a lot to know, especially for TV Booster. usually much less satisfied if it is not equipped with a TV antenna with Booster. for those who like to experiment or hobby electronics, electronics projects please just try this one. the circuit is not too complicated. tolerable if so it can be used for UHF TV antenna at home. UHF antenna booster can be used for the purpose of better reception, especially if you are away from the TV stations / transmitter relay. UHF antenna booster works in the range 400-850 MHz.
Here is a UHF antenna booster circuit diagram : 

The circuit uses only one transistor, with the strengthening of between 10 to 15 dB, good enough for many situations. The most important part is that the transistor circuits must be protected from the input circuit, as shown in the schematic diagram by a dotted line (metal shield / protective metal). it aims to avoid interference. 

Circuit is supplied from a separate power supply via the signal cable (similar to the booster UHF systems that are sold in stores, the power supply inside the house or placed near a TV), because this booster circuit should be as close as possible to the antenna. This is very important because the amplifier must amplify the signal obtained by the antenna, not the noise being picked up by cable between the antenna and the circuit.

Antenna and booster circuit can be mounted on the roof of your house. 75 ohm coaxial cable length can be used from this booster circuit output to the power supply unit is located close to the TV.

Construction is very simple power supply, use a 50-100 uh inductor or RF choke between the output and power supply cables. Small ceramic capacitors 100pF are used to block DC voltage from the power supply. Adjust P1 to get the best reception, and this is to set the current consumption during use which is about 5-15 mA.

No comments:

Post a Comment