Heathkit H9 - Page 41

-
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.