Picture display device comprising a power supply circuit and a line deflection circuit

Claim 1

A power supply and scanning line deflection circuit for a picture display device, said power supply circuit comprising the series arrangement of a first switch (T r1 ) switchable at the scanning line frequency and a first inductance (L 1 ) connected between the terminals of a first voltage source, said first inductance forming part of a first resonant network during the cutoff period of said first switch; said deflection circuit comprising a line deflection coil (L y ) and, connected across the terminals of a second voltage source, the series arrangement of a second switch (T r2 ) switchable at the scanning line frequency and a second inductance (L), the line deflection coil and the second inductance forming part of the second resonant network during the cutoff period of said second switch, the cutoff period of said second switch substantially coinciding with the scanning line retrace period; a transformer winding coupled to one of said inductances; a rectifying circuit including a rectifier connected to said transformer winding for rectifying pulses produced across such winding during the cutoff period of the one of said switches which is in series with the one of said inductances which is coupled to said transformer winding, such rectifying circuit generating from such rectified pulses a supply voltage for a load which may be connected thereto; and means for connecting said transformer winding to the other of said inductances, said connecting means being substantially non-conducting during the scanning line trace period but conducting during at least a portion of the scanning line retrace period to then supply a current to said other inductance which stabilizes the supply voltage produced by said rectifying circuit against variations in a load connected thereto.