Created: Mar 09, 2014
No description available.
This circuit is a two-channel baseband video switcher. Buffer amplifiers U1/Q1, U4/Q4, and associated components produce a buffered 75-Ω video signal, which is routed to switching network relays RY1/RY2/RY3. Relay RY1 selects either of these two video amplifiers and feeds J7. RY2 also routes the output of either video amplifier to RY3, which passes the selected video channel to J8 or connects J9 to J8.
U2 and J3 are audio amplifiers, which drive U7 and J8 to route audio from J1 and J2 to either J14/J15, or J10/J11. Also, audio from J12/J13 can be routed to these jacks.