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| cURSOR JUMPS TO BACK TO HOME POSITION. | cHECK u7 (6510 mpu) |
| aBNORMAL COLORS APPEAR IN THE LETTERS. | cHECK u6 (2114 ram) u16 (4066 ic) |
| dIFFERENT CHARACTERS ARE DISPLAYED AND CURSOR IS LOCKED WHEN TURNED ON AND OFF. | cHECK ram |
| sYSTEM DOES NOT RESET AND THE 'restore' KEY DOES NOT WORK. | cHECK u20 (556 ic) |
| wHITE BAND SCROLLS DOWN THE SCREEN. (60 hz hum) | cHECK eXTERNAL pOWER sUPPLY
vr2 (5v rEGULATOR) |
| cURSOR DISAPPEARS AFTER THE SYSTEM WARMS UP. | cHECK u1 (6526 cia) |
| syntax error DISPLAYED AFTER SYSTEM WARMS UP. | cHECK ram, u3 (rom) |
| wAVY SCREEN AFTER THE SYSTEM WARMS UP. | cHECK eXTERNAL POWER SUPPLY
u31 (74ls629 ic) u30 (74ls193 ic) |
| tHE SYSTEM RESETS WHEN IT WARMS UP. | cHECK u7 (6510 mpu)
u3 (rom) |
| kEYBOARD DOES NOT OPERATE CORRECTLY WHEN THE SYSTEM WARMS UP. | cHECK u1 (6526 cia)
u3 (rom) |
| bLACK BAND SCROLLS THROUGH SCREEN WHEN THE SYSTEM WARMS UP. | cHECK eXTERNAL pOWER sUPPLY
c90, c88, cr4 vr2 (5v rEGULATOR) |
| cASSETTE MOTOR KEEPS RUNNING. | cHECK u7 (6510 mpu) |
| cASSETTE MOTOR KEEPS RUNNING EVEN AFTER A PROGRAM IS DONE LOADING. tHE tip 29 TRANSISTOR GETS EXTREMELY HOT AND THE FUSE MAY POSSIBLY BLOW. | cHECK cASSETTE pORT FOR sHORTS
r4 (pOSSIBLY oPEN) |
| tHE CURSOR DISAPPEARS WHEN THE CASSETTE IS PLUGGED IN. | cHECK u7 (6510 mpu) |
| cASSETTE RUNS EXTREMELY SLOW. tHE PROGRAM SEEMS TO LOAD BUT WILL NOT RUN. | cHECK u7 (6510 mpu) |