Hi all, "Echo" mode, which recently started to appear in WSJT-X, is for users who want to test their station's EME capabilities by measuring their own self-echoes from the Moon.
When you click "Tx Enable" in Echo mode the program goes into a repeated 6-second cycle as follows: - transmit a 1500 Hz tone for 2.3 s - reset the dial frequency to account for EME Doppler shift - receive the echo about 2.5 s later - compute spectrum of received signal - plot spectrum on expanded scale, centered at 1500 Hz For general interest, I've posted two screen shots that show WSJT-X running in Echo mode: 1. Station K1JT at 144 MHz (4x14 element yagis, 1100 W): http://physics.princeton.edu/pulsar/K1JT/EchoTest_4.png 2. Station G3WDG at 10 GHz (3m dish, 100 W): http://physics.princeton.edu/pulsar/K1JT/100Wechomode.jpg The "Wide Graph" is the usual waterfall, typically covering 2.5 kHz or more. The new "Echo Graph" (top left) is a full-resolution spectrum of the received echo. At 10 GHz the measured "Doppler spread" (different Doppler shifts from different parts of the lunar surface) is more than 100 Hz, as shown by the red curve on the Echo Graph. Lots of fun! WSJT-X is slowly becoming a powerful tool for our VHF-UHF-Microwave friends, as well as the HF crowd. -- 73, Joe, K1JT ------------------------------------------------------------------------------ _______________________________________________ wsjt-devel mailing list wsjt-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/wsjt-devel
