diff --git a/doc/user_guide/en/measurement_tools.adoc b/doc/user_guide/en/measurement_tools.adoc
index 1dc367c7d..d7718aa46 100644
--- a/doc/user_guide/en/measurement_tools.adoc
+++ b/doc/user_guide/en/measurement_tools.adoc
@@ -27,11 +27,16 @@ of WWV at 2.500, 5.000, 10.000, 15.000, and 20.000 MHz, and CHU at
 3.330, 7.850, and 14.670 MHz.  Similar shortwave signals are available
 in other parts of the world.
 
+- In most cases you will want to start by deleting any existing file
+`fmt.all` in the directory where your log files are kept.
+
+- Enter `0.0` for both *Slope* and *Intercept* under _Frequency
+Calibration_ on the *Settings -> Frequencies* tab.
+
 - To cycle automatically through your chosen list of calibration
 frequencies, check *Execute frequency calibration cycle* on the
 *Tools* menu.  _WSJT-X_ will spend 30 seconds at each frequency,
-writing its measurements to the file `fmt.all` in the directory
-where your log files are kept.
+writing its measurements to file `fmt.all` in the log directory.
 
 - During the calibration procedure, the radio's USB dial frequency is
 offset 1500 Hz below each *FreqCal* entry in the default frequencies