Apple Disk II Technical Procedures

5. Type LOCK HELLO and press to re-lock the file.If you have replaced all of the ICs on the analog card andthe file still does not unlock, perform the COMPARATOR OFFSETADJUSTMENT located in the calibration procedures of the Disk][ Technical Procedures section. If the analog card stillfails to function properly, place all original ICs in theirsockets and return the card to Apple. Otherwise, go on tothe next procedure.Write-Protect Switch Circuit Malfunctions1. Place a write-protect tab on the DOS 3.3 System Masterdiskette and insert the diskette in drive 2.2. Repeat steps 2 and 3 above (DRIVE HAS TROUBLE WRITING).The video screen should display WRITE PROTECT ERROR. Ifthis does not occur, replace the following device (unlessit has been replaced previously), and repeat this test.- IC at B4 (labelled 74LS125)If the screen still does not display WRITE PROTECT ERROR,place all original ICs in their sockets and return the analogcard to Apple.Disk ][ Analog Card rev Jun 84 Page 5.13