From inside (document excerpt):
1 Instruction Manual EJ-50U Terminal Node Controller Unit Ver.01 ALINCO,INC Thank you for purchasing this fine Alinco product. This unit enables data communication when it is properly installed in designated Alinco transceivers. Please read this manual, print the contents if necessary, and keep this disk for future reference. Since this device is also capable of being used in commercial applications, some of the pages in this manual are intentionally left blank to accommodate those uses in other regions.
Although we attempt to explain the features of this unit in a simple and comprehensive manner, unless you have some knowledge about packet communications and APRS, you may have difficulty understanding the contents of this manual. We apologize, but Alinco cannot provide basic information on how packet and/or APRS functions in general. Please consult your favorite Ham radio stores for books on the subject and/or web-sites that support your area of interest regarding those communication modes. You may also find assistance through a local amateur radio club. You can explore the exciting world of data communications, and we believe that this is a most interesting part of the king of hobbies, Amateur Radio. APRS® is a registered trademark of Bob Bruninga, WB4APR Notice · This unit should be used with ALINCO transceiver DR-620T/E. · The parameter settings are retained by the built-in lithium battery. If the settings return to their default values, the battery may be depleted. Should this occur, consult your Alinco dealer. Please refer to the Alinco transceivers’ instruction manual for the proper installation of this unit. Index 1. Description — 5 2. Commands 6 2-1 command mode and converse mode – 6 2-2 general use of commands — 6 2-2-1 Direct commands 6 2-2-2 Setting parameters – 6 2-2-3 Reconfirming