Video amplifier splitter by transistor BD137-BC547-BC557

This is the video amplifier circuit or the video splitter circuit, it is designed to take video signal is stronger. Compensate for the loss of signal, and is video splitter video, which can connect up to three outputs. so is suitable for display on several television screens, or video tapes recording at the same time too. (Now may will no video tape.)
The advantage of this circuit is cheap, easy and the results are detailed in the circuit below.
How it works
Technical specifications
- Increasing rate Typically, the circuit video amplifier is designed to have low amplifier rates. (it different with the common pre-amp circuit) For our the circuit has the maximum gain ratio is only 4 times.
- Impedance is 75 ohms on both the input and output.
- Bandwidth of this circuit wide is 5 Mhz.
It can be seen that the circuit contains only three transistors. By Q1 (BC547), Q2 (BC557) acts as a signal amplifier, and Q3 (BD139 or BD137) serves as the output circuit of common emitter follower.
The input impedance of circuit is determined by the value of R1. The input signal entered through C2 to the base of Q1. By the VR1 is the set the level of the signal swing.

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