Futaba 10J - Manual (Page 141)

When a governor (CGY750/GY701/GV-1,
etc.) is used, the speed can be adjusted from the
transmitter. CH7 or CH8 or CH9 can be selected as
the speed setting control channel.
When using a separate ON/OFF switch (cut
switch), ON/OFF control uses CH8. In this case,
CH7 or CH9 controls speed setting.
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