diff --git a/doc/user_guide/en/new_features.adoc b/doc/user_guide/en/new_features.adoc index 93a104092..d5fa56193 100644 --- a/doc/user_guide/en/new_features.adoc +++ b/doc/user_guide/en/new_features.adoc @@ -1,15 +1,27 @@ [[NEW_FEATURES]] === New in Version {VERSION} -_WSJT-X 2.4.0_ introduces *Q65*, a new digital protocol designed for -minimal two-way QSOs over especially difficult propagation paths. On -paths with Doppler spread more than a few Hz, the weak-signal -performance of Q65 is the best among all WSJT-X modes. +_WSJT-X 2.5.0_ introduces an enhanced Q65 decoder that measures and +compensates for linear frequency drifts of Q65 signals. Activate this +feature by setting a spinner control *Max Drift* on the _WSJT-X_ main +window to a number greater than 0. We suggest a setting of 10 for +submode Q65-60A, the recommended submode for EME on 50 and 144 MHz, +which will accommodate drift rates up to 20 Hz/minute. Similarly, we +suggest *Max Drift* = 40 for submode Q65-15C, used for for 10 GHz QSOs +(up to 900 km) via aircraft scatter and drift rates up to about 20 +Hz/s. -Q65 uses message formats and sequencing identical to those used in -FST4, FT4, FT8, and MSK144. Submodes are provided with a wide variety -of tone spacings and T/R sequence lengths 15, 30, 60, 120, and 300 s. -A new, highly reliable list-decoding technique is used for messages -that contain previously copied message fragments. Message averaging -is provided for situations where single transmissions are too weak or -signal enhancements too sparse for a signal to be decoded. +On the Windows platform only, _WSJT-X 2.5.0_ installations now include +an early version of _MAP65 3.0_. This program works together with +suitable hardware that converts RF to baseband. The hardware/software +combination implements a wideband, highly optimized receiver for the +Q65 and JT65 protocols, with matching transmitting features that +require a standard SSB transceiver. _MAP65_ is effective in both +single-polarization and dual-polarization systems. If two +polarization channels are available, _MAP65_ determines and matches +the linear polarization angle of each decodable signal. This +capability provides a major advantage for efficient EME communication +on bands up to 432 MHz. A single-channel _MAP65_ system works +extremely well for EME on 1296 MHz and higher bands, displaying all +signals in a 90 kHz sub-band and decoding all the Q65 and JT65 +signals.