Different decoding parameters can be selected in each MMTTY and/orĢTone instance to cover a wide range of reception conditions such as QRN, QSB,Ĭhoice of AFSK vs. One of the decoders will have clear copy, eliminating the need to request Up multiple, parallel decoders is “free” and provides a higher probability that
#HAM RTTY SOFTWARE#
With your logging software used for CW and SSB will be a likely first step to ForĮxample, the logging capability in MMTTY is very minimal, so MMTTY integration This starting point, refinements can be made to enhance your RTTY operation. MMTTY configuration, reception and transmission of RTTY is achieved. Then, use MMTTY standalone to complete the system.
#HAM RTTY PC#
Summary, the simplest way to get started in RTTY is to connect a stereo receiveĪudio cable and a monaural transmit audio cable between the radio and PC The Mark signal is the higher RF carrier transmitted and received. The MarkĪnd Space logic can be swapped with Invert checkboxes in a couple places to ensure Or FSK is selected in the MMTTY encoder, or TX, configuration windows. Most FSK users start with using the MMTTY
#HAM RTTY SERIAL#
Hardware UART in the Serial interface, or via an outboard dedicated processor If the PC has no legacy Serial COM ports.Īre three methods of generating the FSK bit timing: software within MMTTY, Level translator to the radio’s FSK input. It isĪ cable connected from a PC Serial COM port through a simple NPN transistor Requires a keying interface, which is identical to a CW keying interface. Make the higher RF frequency the Mark signal. Radio configuration menu has a parameter to swap these definitions if needed to Voltage is usually defined as the Mark and low, or ground, is the Space. Input is “keyed” similar to the Key input for CW transmission. AnotherĪudio cable, typically monaural, is then connected from the soundcard to theĬan be used if the radio has an FSK input (most modern radios do). Space are generated by MMTTY and sent to the soundcard playback output. For AFSK, the two audio tones for Mark and Lower audio tones are more comfortable to listen to,Įspecially over extended operating periods. Partners can each use different local audio tones without knowing what the The tone choice only affects the local operator, similar toĬhoosing the audio sidetone frequency, or pitch, for CW reception. Two MMTTY instances can run inĭefault audio tones are 21 Hz but can be changed to the operator’s On which receiver is desired for decoding. In MMTTY, theĬonnected soundcard is selected as well as the left or right channel depending Usually, a stereo audio cable is used toĪccommodate both the main and sub receivers in the radio.
A simple audioĬable between the radio and PC is all the hardware needs. Input, which is then accessed by decoder software such as MMTTY. RTTY requires that the receiver audio is connected to the PC soundcard recorder Another popular RTTY decoder/encoderįreeware application is 2Tone, introduced in 2012 by G3YYD. Logging software such as DXLab Suite, N1MM+, etc. This RTTY software is usually integrated with Introduced by JE3HHT, almost all decoding (and encoding for transmission) hasīeen done in software on a PC. If any, humans are skilled at decoding RTTY signals in their head, so hardware The Mark signal depending on whether the radio is in LSB or USB mode. Therefore, either the higher or lower audio tone will be The higher audio tone on one’s headphones will be the lower RF frequency if the This is how spots should be expressed, for example. The standard for specifying an RTTY frequency is to use the Mark The higherįrequency RF carrier is called “Mark” and the lower one is called “Space.” The MarkĪnd Space are often referred to as “tones” because they are two audio tones in The “shift” and is commonly 170 Hz in almost all amateur RTTY today. Two RF carriers have a fixed frequency difference between them. The two carriers are exactly symmetrical and therefore The RTTY signal itself consists of two RF carriers that are switched on and It helps to have a clear picture in one’s mind of how the mode works in order to solve the inevitable configuration issues that are frequently encountered, even by experienced RTTY operators.
Just following instructions is often not successful. Getting started in the RTTY mode can be confusing and frustrating.
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