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+# Calibration
+HOWTO calibrate an Alfaspid RAS with a
+Green Heron Engineering RT-21 Az/El.
+
+See also documentation from Green Heron:
+"RT-21 Az-El Controller: Manual addendum to RT-21 -- August, 2021"
+
+
+This assumes all cabling is set up and complete.
+See documentation about wireharnesses in main Mighty docs.
+
+# Procedure
+
+* Plug in everything.
+
+* Power on.
+
+* Go to SETUP/CALIBRATE.
+
+* Turn panel knob until actual value matches "NEW VALUE".