Substitute : A255D , TDA2591 , TDA 2593
Functions :
- Sync Separator
- Vertical Sync Separator
- A.F.C
- Horizontal sync Separator
- Burst gating and Horizontal blanking pulse generator
| Pin No. | Functions | Voltage |
| 1. | Positive (+Ve supply voltage) | 12 |
| 2. | Positive (+Ve supply voltage) output stage (Trigger pulse input) | 12 |
| 3. | Horizontal trigger pulse output (15625 Hz.) | 1.2 |
| 4. | Selection of output pulse duration | 0 |
| 5. | Decoupling capacitor | 6.5 |
| 6. | Horizontal flyback (blanking)pulse (15625 Hz.) for 2nd phase comparator | 0.2 |
| 7. | Sandcastle (Horizontal blanking pulse) output (15625 Hz) | 1.8 |
| 8. | Vertical Sync output (50 Hz.) | 0.2 |
| 9. | Sync pulse input | 1.6 |
| 10. | Noise separator input | 2.2 |
| 11. | VCR switching ( Coincidence ) | 5.7 |
| 12. | Time constant switching ( third phase coparatior ) | 2.2 |
| 13. | First phase comporator output | 6.1 |
| 14. | Ramp ( sawtooth ) oscillator capacitance | 6 |
| 15. | Horizontal frequency ( 15625 Hz. ) adjust (H-Hold) | 6 |
| 16. | Ground (-Ve supply voltage ) | 0 |
