B&K 1076, Инструкция по эксплуатации

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tube. The vertical output tube itself is removed from the set. In
sets where the heaters are series-wired, the filament terminals on
the socket can be shorted out, so that all the other tubes in the
series string will continue to operate.
We are now driving the output transformer from the vertical out­
put stage contained within the TV Analyst. However, the B+
applied to this remote output stage in the instrument is derived
from the receiver circuit itself. If vertical deflection is restored with
this plate signal, the defect is in the vertical output stage, generally
in the cathode circuit, assuming the tube to be good. If the vertical
deflection is still missing then it indicates that either the vertical
output transformer or the vertical windings of the deflection yoke
are at fault.
We are assuming, in the preceding paragraph, that B+ is reaching
the plate of the vertical output tube. This B+ is required by the TV
Analyst to power its output tube. If no B+ should be present, no
signal will be obtained from the PLATE DRIVE terminal. Hence,
if application of the test lead from the instrument at the plate of the
output stage does not produce vertical deflection, it would be desirable
to check the voltage in this circuit to make certain it is present.
Absence of the necessary voltage indicates an open circuit in the
vertical output transformer winding, or an open resistor or shorted
capacitor in the B+ network bringing this voltage to the vertical
system.
To check the vertical windings of the deflection yoke, disconnect
its wires from the circuit and connect them to the two test leads from
the Vertical Yoke Test Signal jack and GROUND of the TV
Figure 14-Sweep developed using vertical yoke test signal
Analyst. If the yoke is good, vertical deflection of the picture tube
image will result. The image will possess poor linearity and overlap
or go back itself (Fig. 14) because the driving signal is a sine wave
and not a sawtooth. However, we are not concerned here with check­
ing linearity and, therefore, any indication of deflection would reveal
the 'yoke to be good. The trouble now is definitely indicated to be
in the vertical output transformer.
TROUBLE SHOOTING HORIZONTAL DEFLECTION CIRCUITS
We come now to the horizontal circuit of a television receiver and it is
here that the instrument offers the service technician several quick test
features that will greatly simplify the task of servicing this section of the set.
One such outstanding feature is the ability to check the output circuit
completely, both from the grid of the horizontal output tube and from the
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