Service manual

STP 11-25R13-SM-TG
G - 2
c. If the output signal on the collector of Ql is missing, check Ql and its load resistor (R3). If Q2's
collector signal is missing or incorrect, check Q2 and its load resistor (R5).
d. After completing signal tracing, DC voltage measurements will isolate the malfunction. Keep in
mind that there is a 24V difference in potential between -V
CC
and +V
CC
and the sum of the individual
voltage drops should be equal to 24V. After measuring DC voltage, confirm the suspected malfunction
with ohms testing.