The Technisonic TBS 100/200/300 series of Desk top base stations are high performance, synthesized, six channel transceivers which cover the VHF/AM aeronautical band from 117.975 MHz to 138.000 MHz with 25 KHz channel spacing. Operating frequency for each channel can be programmed in the field by service personnel via an internal jumper matrix. Optional TLI-203 Line Interface card (Part No. 923051-1) provides for remote operation via a two or four wire interface supporting 2175 Hz Tone keying, DC keying (15 ma) or Ground keying. The TBS series offers exceptional adjacent channel rejection and superb receiver sensitivity. Nominal transmit power is 7 Watts for the TBS-100, 15 Watts for the TBS-200 and 25 Watts for the TBS-300. These transceivers provide a trickle charge output from the rear panel of the radio for purposes of maintaining a battery (not included). In the event of a power failure, the transceiver (if connected to the battery) will automatically change over to operate on battery power.