User guide

MS-DMT Guide v1.04

Released 05-30-2014

Military radios run their receivers wide open, they do not provide the type of receiver features

found in most Amateur and some Commercial radio equipments. In taking some of those non-

Military radio receiver features into consideration the following settings are recommended:

 IF BW as close to 2.8kHz on TX as possible and no more than 3.0kHz on RX.

 IF Shift if equipped, set to 1800Hz instead of 1500Hz center if using filters under 2.8kHz.

 The longest receiver time constant of the automatic gain control (AGC) circuit must be

used to prevent rapid gain changes arising from channel fades. More than 10ms on

desensitization and less than 25ms on resensitization is required. Thus if AGC is

selectable, SLOW or MEDIUM or perhaps even OFF should be used depending on the

characteristics of the make/model radio being used.

 Receiver NOISE BLANKER for pulse type noise that is not DSP based can usually be ON if

really required, but on some radios it may need to be OFF, experimentation with the

given radio in actual use of the DMT tool will be required.

 All receiver DSP features such as NOISE REDUCTION, DUAL WATCH etc. should be OFF.

 Receiver NOTCH FILTERING of any type must be OFF.

 Receiver SQUELCH should be wide open. However it can be adjusted so as to quiet

channels where the user suffers from a high noise floor to the point where the channel

with the lowest noise level is squelched except when the system is being used for ALE

for linking prior to the use of this software.

 Receiver RF GAIN should be full open, especially for unattended use, however the user

can adjust it to quiet the receiver if needed. The same is true of using an ATTENUATOR.

 Some receivers that have additional IF stage filer selections where filters are at a low IF

frequency and a high IF frequency, if selectable for bypass, the higher frequency IF filter