Sony KV-13FS100 Product & Training Manual page 23

If all the above tests are passed then either the Horizontal Output transistor or the FBT is defective. The
Horizontal Output transistor can be checked using an Ohmmeter. The Base-Emitter junction should check the
same as a normal BJT. When checking the Collector-Emitter junction, note that a diode is connected in parallel
(the C-E junction will test the same as the B-E junction).
If Q505 or 506 checks OK then replace the FBT.
NOTE: The amplitude of the HD at the collector of Q505 or Q506 is approximately 1000V. If attempting to make
a measurement at this point, use a X10 probe and make sure the oscilloscope can handle the power at its input.
Pincushion Circuit (reference Figure 4-3)
An inverted parabola waveform is used to control the amount of drive current supplied to the FBT to compensate
for the pincushion distortion. The E/W signal (inverted parabola) is output on IC001/pin 47 (ref. Waveform 4-1)
and passes through Buffer/Amp IC565/pin 5 to IC565/pin 1 (ref. Waveform 4-2). The signal is then applied to
gating circuit IC561/pin2 and the HD pulse on IC561/pin 3 (ref. Waveform 4-3) is used to gate the parabola
waveform through at the horizontal rate. The resultant signal is output on IC561/pin 1 is amplified by Q521 and
Q522. The output signal of Q522 is applied to the anode of D505 (ref. Waveform 4-4) and controls the conduction
of D505. Depending on the level of conduction of D505, the current supplied to the FBT will increase or decrease.
Oscilloscope
Settings:
0.2V
5ms
IC001/Pin 47 (Inverted Parabola)
Oscilloscope
Settings:
0.1V
20ms
Waveform 4-1
IC561/Pin 3 (HD Pulses)
Waveform 4-3
Oscilloscope
Settings:
0.5V
5ms
Oscilloscope
Settings:
50V
5ms
D505 Anode (Inverted Parabola)
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4. Deflection Circuits
IC565/Pin 1 (Parabola)
Waveform 4-2
Waveform 4-4