Does this support 'Smart search' i.e. search for a change in a particular part of a picture from a camera
This System does not support any analytic search functions, it has standard Motion Detection and alarming function.
Are these HD cameras?
Yes, these are 2 mega pixel AHD (Analogue HD) Cameras.
How do you connect an IP camera to this DVR?
Firstly you will need to login to the unit , go to System -> Digital -> Channel type, then select the configuaration that supporst IP. An IP camera is then connected to this unit via it's RJ45 (lan port) using a network switch or POE switch.
can you use analogue cameras lower than 960h capability on this dir?
Yes these will be compatible with this DVR.
Price per pair or single?
TT-105a is sold as a pair, Price displayed will be for a pair.