Atari 800

800 TONE
TEST
(cont)
la
R157
(IK) shorted
YP.^
Repair
and retest
NO
VTTSAre
Ciai(l.uf).
R167{18K),
or
R195(4.7K)
epen
Repair
and retest
VP«I
NO
Are
C178(,0OIuf),
ClS0(.22uf).
or
R166(1K}
shorted
or
open
Repair
and
retest
YT?.<?
NO
Can
you verify
the
following;
1)
4.5 MHz
.oscillation
by
connecting
a
scope to
the
emitter
of
QI06
2)
A
sine wave
^ 2.3
centimeters
3
.luS/Div
and
20mV/Div
which
equals
^
4.SMHZ
3} Can
you
adjust
LlOl
to
equal
4.5MHz
Verify
input to
Audio
>\4ixer
by
connecting
scope
(.5mS/Div,
5mV/Div)
to
collector
A 104,
Pin 2
Are
waveforms
same
as AlOl,
Pin
37 (except
wave-
form
is
rounded,
not
square)
NCI
Return
to
START.
Page
7-24
YES
NO
Repair
and
reteat
Is
there
output
on
A104,
Pin
5 (scope
.5mS/Div.50mV/Div)
NO
Replace
A
104 and
Tfitrmt
YES
Go to
next
page
ATARI
Home
Computer
7-26