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TV signal amplifier 470Mhz-860Mhz

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This amplifier can amplify to 10dB the RF signal from antenna working as class A and is based on transistor BFQ34 of Philips. The transistor comes in case SOT122A. You may find the BFQ34T in market but better do not use it as it has different characteristics.
TV signal amplifier 470Mhz-860Mhz



Input signal should be about 10mW if we want 10dB output. So with 0.5mW we get 5dB. Do not overdrive the transistor because the signal will be distorted full of lines, without color etc. So use 12Volts with 1A stabilised power supply. The circuit should be enclosed in a small metal box.


Datasheet file1: Click here to download BFQ31.pdf datasheet.


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