* For TDR-2209 there are only 9 camera Inputs and 9 Loop through outputs on the back board. For TDR-2204 there are only 4 camera Inputs and 4 Loop through outputs on the back board. 1. Camera Inputs 2. Loop Through output 3. Reserved 4. CCTV Monitor output 5. Alarm Inputs 6. Alarm Outputs 7. Audio In 8. Microphone Jack 9. Audio Out 10. COM series port 11. Printer (LPT) port 12. PC Monitor Output 13. Mouse (PS/2) 14. Keyboard (PS/2) 15. Network port (RJ-45) 16. AC Power Input 17. 115/230 VAC Powe