Limiting Transmission Range

Listen Technologies recommends transmitting no more than six (6) simultaneous FM channels on 72 MHz and three (3) simultaneous FM channels using the 216 MHz frequency band, in the general vicinity of each other. However, there are some projects (educational facilities or large buildings) where more frequencies are required in a large area, but not all in the same room. For example, some educational facilities may have classrooms scattered over a large building. If transmitters are placed in each of these rooms, the frequencies may have interference if they are placed too close to each other.

The purpose of this post is to show an alternate approach for allowing more frequencies in a general area by limiting the range of each Stationary Transmitter. The LT-800 Stationary Transmitter has the ability to decrease the transmission power, but the range on the lower setting may still be too large. By drastically minimizing the range of the Stationary Transmitter, more units can be placed a general area. This note will describe how to minimize the range without altering the electronics of the unit.

Watch this video to understand how to achieve limiting the transmission range.