Tested, Warranted To INSTAL / CHANGE the battery --Battery would sit in the tray facing up(positive up) /SEE PIC 1MB BLANK RAM Card for use with HP 48GX Expandable Graphic Calculators Checking the RAM Card 1--Make sure the write protect switch is in NO position 2--Turn the calculator ON 3--Insert the Ram card in PORT 2 (in port one, you will get a black screen) 4--If the calculator goes OFF, simply turn it back ON with the Ram card in it 5--Ignore Invalid Card Data OR Low Batt (P2) Warning messages 6--Press and hold the ON key, Press the 4th menue key (' D '), Then release both 7--Three vertical line will appear ( You might have to do step6 a few times to get the 3 vertical lines) --Now press the up-arrow key --After a while (hash screen) , you will see the 1st block (128KBytes) on the.
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