2.5.3 Audio signal input
RCA Audio input.
The input impedance is high so the tone arm must be active.
The audio signal line should be firm and away from the electro magnetic Interference and connected
credible which avoid false and joint welding and oxidation. The high voltage current should be avoided
especially.
2.5.4 Audio signal output
Commonly the output parameter of DVR audio signal is greater than 200mv
1KΩ (BNC) which can
connect the low impedance earphone and active sound box or other audio output equipments through
power amplifier. If the sound box and the tone arm can not be isolated, howling phenomena is often
existed. There are some methods to deal with the above phenomena.
1. Adopt better directional tone arm.
2. Adjust the sound box volume to be under the threshold that produces the howling phenomena.
3. Use fitment materials that absorb the sound to reduce reflection of the sound.
4. Adjust the layout of the sound box and the tone arm.
2.6 Speed dome connections
1. Connect the 485 lines of the speed dome with the DVR 485 interface.
2. Connect the video line with the DVR video input.
3. Electrify the speed dome.
RS485 Connector
