Synchronization Separator Schematic Circuit Diagram
Television Receiver Sync Signal Separator Circuit
Synchronization Separator: This circuit serves the purpose of isolating synchronizing pulses from the video signal within a television receiver. The sync signal separator, with its straightforward design, effectively breaks down the composite sync signal into distinct horizontal and vertical sync signals. The resulting composite signal can be directly utilized to drive the monitor’s horizontal sync input.
Functionality of the Synchronization Separator Circuit
Acting as the vital intermediary between diverse video sources and a multisync monitor, this circuit is constructed using discrete components. Its primary function is to extract composite synchronization, a combination of horizontal and vertical components, from a composite video signal with an amplitude of approximately 1 Vpp. The output sync signals are provided in both true and inverted forms, catering to the requirements of your monitor.
Positive Composite Video Signal Processing
To extract sync components, the positive composite video signal undergoes filtration through R1-C2 and clamping via a Schottky diode, D1. The resulting CSYNC signal is directed to XOP crate N2, which acts as an inverter when S1 is closed.
Two-Stage L-C Filter for Sync Signal Separation
The CSYNC signal is further channeled through a two-stage L-C filter, effectively suppressing the line sync component and retaining the raster sync. The VSYNC signal, available at the inputs of opamp IC lb, mirrors the characteristics of CSYNC and can be obtained in true or inverted form. The circuit’s power consumption is around 200 pA at a 5 V supply voltage, and the output signals are TTL-compatible.
Parts list
Resistors:
- Ri, R6 = 11kΩ
- R2 = 1 MΩ
- R3, R5, R8 = 22 kΩ
- R4 = 220 kΩ
- R7 = 10 kΩ
Capacitors:
- C1 = 15 nF
- C2 = 330 pF
- C3 = 10 uF, 16 V, radial
- C4 = 47 uF, 16 V, radial
- C5 = 33 nF
- C6 = 2.2 nF
- C7 = 68 nF
- C8= 1.5 nF
- C9 = 33 nF
Semiconductors:
- D1 = BAT85
Integrated circuits:
- IC1= TL,C272
- IC2 = 4030BE
Miscellaneous:
- L1. L2 = 47 mH choke, radial
- K1, K2, = phono socket for PCB mounting
- S1 and S2 are miniature on-off switch
- PCB Ref. 914077