Raymarine SL72 Owner's Handbook Manual page 104

Chapter 5: Standard Chart Operations (SL72RC PLUS only)
3. Edit the Loran parameters as required, using:
i. The CHAIN soft key, which enables selection of both the Chain and it's
ii. The ASF1/ASF2 soft key, which presents two soft keys for editing ASF 1
iii. The SET TD 1 and SET TD 2 soft keys, which enable editing of each TD's
Note: Except for the CHAIN setting, parameters are edited using the trackpad
as described in Editing the Waypoint Details on page 5-13.
4. When editing is complete, press the ENTER key to save the waypoint or
CLEAR to cancel the operation; the display returns to the New Waypoint
screen.
Press the ENTER or CLEAR to return to the Waypoint List.
WPT POSITION (LORAN TDs)
Slave:
WPT POSITION (LORAN TDs)
and ASF 2 parameters independently :
parameters independently.
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