Distribution
Amplifier (VDA)
Installations that require the viewing of one video source from
multiple locations in a building must use a device that duplicates the
original signal, a video distribution amplifier (VDA).
This device reproduces the original video signal into multiple copies,
one for each monitor in your system.
Most people will not notice signal degradation (a loss of picture details)
in up to 400 foot runs of coax cable.
Video signals in your home system and in security or CCTV equipment
have common traits;
The signal that travels through the cable is one (1) volt peak-to-peak.
It can be viewed on any monitor or TV with a video input.
It has a characteristic impedance of 75 ohms.
It can be degraded by ground loops and long cable runs.
Equalizing Amplifier
A camera to monitor distance of over 750 feet through RG59 coax
will display a weak and degraded picture on the monitor. This effect
gets worse as the cable gets longer. A simple fix passes the weak signal
through an equalizing amplifier and after making the required adjustments,
you will have a strong signal that will produce a good picture.
A post-equalizing amplifier is a device that is installed close to the
monitor (as opposed to close to the camera). AC power is usually more
readily available at the monitoring location and only one person is
required to view the monitor and at the same time make the required
adjustments to the equalizing amplifier, for the best picture. |
Home Page > Video Only Distribution Amplifiers 
