Large Phased Array of the P.N. Lebedev Physical Institute is the most sensitive in the world at the metre waveband. It allows simultaneous observation of two independent diagrams each consisting of 16 beams. We are planning to introduce a program of monitoring interplanetary and ionospheric scintillation using observations of radio sources by one multi-beam diagram. The methods of observations and data reduction are discussed. We present the first results of seven day test observations for a strip of the sky in a region with declinations between 28^° and 32^° by using an eight-beam diagram.