Handheld TV User Manual

The
keys of Keyboard
B
"write"
on the
screen according
to the white
arrowheads on the keyboard (Fig. 15).
To
form
an interesting
pattern, press "Clear" key,
then A2, B2 15
times,
B6 once,
and
then
BO.
The memory stores up to 130
key entries or "moves". After
130
moves,
the
computer auto'
matically starts
to repeat the pattern.
For 129 or fewer moves.
Key
BO must
be pressed to start the
repeat cycle.
KEYBOARD
A
KEYBOARD
B
f
aha
I
nan
;
a
l
B Studio II
©
CLEAR
KEY#0
STARTS
COMPUTER
PATTERN
Figure
15.
Keyboard "B"
Moves Spot
According to
White
Arrowheads
on
Panel
"Doodles"
Function
Press
"Clear"
key. Press A1
.
Single
dot appears on screen
at
lower
left
corner. Use keys
on Keyboard B to move spot
according
to white arrows
on panel (Fig.
16).
Key
B5
leaves
a
trail
as player "writes"
with Keyboard
B.
Pressing
Key BO
leaves no
trail. Retrace
steps to erase lines already written.
Figure
16. In "Doodles", etch
a
sketch
electronically with the
"B" keyboard
Keyboard Tests
If "Tester I"
cartridge is
available, use
it
to
isolate
keyboard
malfunction.
If Tester I is
unavailable,
the keyboards
can be
tested using the
built-in
"Addition" game:
Step
1 : Punch
up
"Addition"
game (Key
A5).
Sound switch
must be "on".
Step
2:
When the
three-digit
number appears
on screen,
enter
a
series of
wrong answers,
beginning
with A1
.
As each
button is pressed, the
beeper sounds,
indicating
the
particular
button is operational. The
beeper sounds
only
during the
five
seconds that the
random-order
display
is
on
screen.
Usually,
the entire keyboard
can
be
checked during the
five-second
display. If
any
key
fails
to
sound, that
key is
faulty and the
entire keyboard
should
be
replaced.
am
ana
13D
KEY
#5 START
PLAYER A
ENTERS
Q
\___
r\~~.
\
io ni
B
o\po
DDD
DDD
a
Studio 11
DDD
DDDD
DDD
<
©
CLEARI
^
—
—.
—
PLAYER
B
]
ENTERS
'
SUM
Figure 17.
Using "Addition" to Check Keyboards
"Double-Hit"
Keyboard Complaints
Some
early
production units (Serial Nos. 37125 and lower)
occasionally
exhibit
a
keyboard malfunction termed "double-
hit"
when Studio II operates in the "Patterns" mode (un-
wanted
dots appear on the screen,
and the
beeper sounds
twice for
only one key entry). The only remedy
for
double
hits is
keyboard replacement.
Coaxial Cable Tests
The
coaxial
cable carries
modulated RF from
the console
and DC from
the power
unit.
Use
an
ohmmeter to test the
cable
from the plug end (Fig.
1
8).
A good
cable
measures 5
to
*J
J
CABLE CONNECTOR
I—
/©n
—
OHMMETER
N
Z>««">
s~^
I
I
I
4-
""J
Figure
18. Checking Continuity
of Co-ax Cable
8