User guide

MS-DMT Guide v1.04
Released 05-30-2014
71
wider filter installed. For reliable performance at data rates of 1200bps and higher the
transmitting station must be using filters of 2.7-2.8kHz.
Above is the passband display of an old TS-450 captured while monitoring a 4Mhz channel
where its 2.4kHz first IF filter is selected and the 2nd filter is in the THRU position and the IF Shift
set at the normal 1500hz center during the intercept of MS110A from a station using 3kHz
filtering on TX. The passband displayed below is the same TS-450 being and the same station
transmitting, the difference being the IF Shift is now adjusted to above center to pass beyond
3kHz.
The vertical yellow marker in both images depicts the MS110A standard 1800Hz PSK carrier in
the passband. Even the old TS-450 and is 2.4kHz filter when using IF shift can be adjusted to pass
a full 3Khz 110A signal on RX for good decode. However this particular TS-450 will suffer as to
the maximum data rates on TX as the passband will be restricted to the installed 2.4kHz filter.