Tandy 1400LT Service Manual page 133

@ IRGB Check
Q
Check the connectors
and cable connected
to the Monitor.
I
Is Monitor switch
(SW2) ON?
I
1
Check frequency of CTL2
It
must be 21.4772MHz.
Check Pin1 and Pin19
of IC31.
CRTG ENABLE signal
(Low level
is
output from
Pin30 of CATE3)
NO
I
Check
IC31 and GATE3.
Check waveform
CN1: 3, 4, 5,
6, 8
and
9.
I
Check
IC31 and IC30.
I
Change
Monitor.
END
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