Editing SimTX Transmitter

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This page describes the legacy Java client. The SimTX app is the recommended client; start with [[Getting Started]] and the [[SimTX Guide]].

'''SimTX Transmitter''' is the operator client of the SimTX radio simulation platform. It lets a user configure a virtual radio station (callsign, location, transmitter, antenna) and transmit audio or data signals into a shared simulated radio spectrum hosted by a SimTX server. Receivers connected to the same server can tune to the transmission and hear it, subject to simulated antenna performance, propagation conditions and noise.

== Start with one task ==
New to SimTX? Follow [[Getting Started]] for downloading, account sign-in, and an audio-file transmission. No knowledge of antenna formulas or Lua is required.

The basic path is '''audio source → transmitter → simulated radio path → receiver'''. The transmitter app controls the station. A separate receiver lets a listener choose a frequency and hear the result. Both use the same server.

For a control you cannot identify, use [[Transmitter Interface]]. For a term you do not recognize, use [[Radio terms]].

All transmissions are simulated; no physical radio equipment is required.

== Overview ==
A transmitter session works as follows:

# The operator starts the application and signs in to a SimTX account, then selects an official server.
# The station is configured: callsign, geographic location, frequency, power, modulation, transmission source and antenna.
# The operator presses '''Start TX'''. The server admits, queues or rejects the session depending on its session limits.
# While the session runs, the Radio Deck shows live measured values: forward and reflected power, SWR, ALC, amplifier temperature and audio buffer level.
# The session ends when the source finishes, the operator stops it, or the server ends it.

== Main topics ==
* [[Getting Started]]: installation, connecting to a server, first transmission
* [[Transmitter Interface]]: reference for every control in the application window
* [[Modulation Modes]]: supported modes and their bandwidths
* [[Transmission Sources]]: audio files and URLs, microphone, white noise, PipeWire, GNU Radio IQ
* [[Lua extensions]]: modulation modes, audio add-ons, tools, themes, and libraries
* [[Extension catalog]]: shared extensions and complete station presets
* [[Radio Presets]]: built-in transmitter characteristics, from clean lab exciters to overdriven CB rigs
* [[Advanced Transmitter Settings]]: the fifteen fine-tuning parameters
* [[Station Configuration]]: callsign, location and saving station presets
* [[Antenna System]]: how antennas behave and are configured, with a page per antenna type
* [[Antenna Calculations]]: resonant lengths, SWR, gain and loss arithmetic
* [[SWR and Transmitter Protection]]: what happens when the antenna is mismatched
* [[Power Amplifier Behaviour]]: heating, power foldback and permanent damage
* [[Sessions and Queueing]]: admission, queue positions, rejections and kicks
* [[Propagation Basics]]: what determines whether a signal is heard at a distance

== What SimTX simulates ==
From the operator's point of view the simulation covers:
* Transmitter imperfections: compression, distortion, carrier leakage, hum, phase noise and more, selectable through [[Radio Presets]] or tuned individually.
* Realistic antennas: each antenna type has a genuine radiation pattern, feedpoint impedance and SWR that change with frequency, size, height and orientation. Custom antennas can be imported as NEC decks, see [[NEC File Import]].
* Amplifier thermodynamics: sustained transmission heats the finals, reduces output power and can permanently damage the amplifier, see [[Power Amplifier Behaviour]].
* Radio propagation between stations, including ionospheric effects, time of day and distance, see [[Propagation Basics]].

[[Category:SimTX]]