Heathkit H9 Manual page 41

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ry
CONDITION
POSSIBLE CAUSE
41. Multiple cursor movements. 1.
Cursor movement latches on the keyboard circuit board.
1c407. 1c408. Q401.
42. Cursor does not blink for hold screen.
1. No 3.75 Hz. 1C401 .
2. tc741c.
3.
Cursor chain on character generator circuit board. 1C202,
lc201c, lc298A, rc218B.
43, No cursor movement on line feed, carriage return, or back
space (control H).
1. Special character detector. lC617A, 1C614, 1C623, lC6178,
lc61 7c, lc61 7D, lc624o, lC624D.
2. Special character decoder. lC703A, lC703B, lC703C, !C7O4B,
tc707c, 1c702.
3.
Speciaf character latch. lC72O, IC74OC, IC74OD, lC721C,
tc721D, tc708D.
4.
No 1C signal. 1C728.
44. Cursor (or the blank line) moves to the wrong position after
a scroll.
'f .
More than one scroll count up. 1C506, 1C522, 1C724, lC73O.
45. Cursor dosen't home following the erase page function.
1. tc723B, tc740A.
I/O PROBLEMS
CONDITION
POSSIBLE CAUSE
46. No serial input or output (general).
1.
Serial cable incorrectly wired.
2.
l/O circuit board not jumper wired for the proper serial config-
uration.
3.
Wrong baud rate.
4. No baud rate. 1C601, lC6O2, 1C607, |C6O8A.
5.
UART 1C612.
6.
UART pins NP, NBl, NB2, or EPS incorrectly wired (umpers).
7. Off Line key pushed in.
8. Reader start must be operative (Q604 must have the base
grounded or current must be flowing in the reader start loop).
47. No serial EIA input.
1.
2.
3.
4.
Jumper wires incorreclty installed.
D604, D602 installed backward.
Q603.
Check the DAV output of lC719C (DAV'), lC725A, lC713C.
48. No TTY input.
1. Jumper wires incorrectly installed.
2. D603, D602 installed backward.
3. Q603.
4. Check the DAV output of lC719C (DAV'), lC725A, lC713C.
49. No TTL input. 1. Jumper wires incorrectly installed.
2. tc609c, tc609D.
3. Check the DAV output of lC719C (DAV'), lC725A, lC713C.
50. No input from parallel or UART.
',| .
Terminal in hold screen mode. lC6158. lC615D.
2. Plug P601-23 shorted to ground.