Introduction to DAMM


Introduction to DAMM

The DAMM system is developed as an audio surveillance system utilising the mains network of houses and buildings as the intelligence transport media. By design, the DAMM makes use of very short, but extremely powerful spread spectrum type pulsations at very low frequencies in the HF area. The technique and modulation scheme used makes the carrier signal from the DAMM transmitter interrelate into any conducting metal in its vicinity – i.e. telephone wires, audio cables, TV cable cabling, water pipes, gas pipes, fire escape ladders, metal staircases and other types of conducting metal.
The transmitter injects an audio modulated complex RF signal across an arbitrary neutral/phase pair of 120/240  60/50 Hz mains power lines at the monitoring site this RF signal travels through the mains wiring to the mains outlets in the neighbourhood of the monitoring site and can be picked up at the listening post by the DAMM RX or via the DAMM mainstay adapter

Working principles of DAMM

Posts Burst Time Modulation

The DAMM system relates to a novel pulse modulation principle PBTM (Pulse Burst Time Modulation) designed by the manufacturer in which both the transmitter and receiver are free running as per the design.

This is an extremely complex method of communication in which only very short and widely separated pulses of energy are transmitted on a low-frequency, enabling very high peak power transmission. Our DAMM pulse modulation system provides a low susceptibility to noise and interference and is very difficult to detect and intercept by third-party technical surveillance countermeasures (TSCM).

The DAMM system has a high degree of noise immunisation and multipath rejection provided by closing off the receiver sensitivity to incoming signals of any kind during the interval between incoming system pulses. In this pulse modulation system, audio information is conveyed by varying the interval between the spaced pulses of translated energy.