B&K 1076, Инструкция по эксплуатации

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FROM
until the test indicator lamp just goes out. Connect the flyback trans­
former to this cable. The connection is made from horizontal output
plate cap connector to hi voltage rectifier plate cap connector. If the
test indicator glows this indicates that the transformer has shorted
turns. This test will respond to as little as one shorted turn. If
the component to be tested is the horizontal winding of the deflec­
tion yoke, connection is made across the deflection yoke winding. It
is also important to test the yoke for leakage between the vertical and
horizontal winding and from the horizontal winding to the metal
frame of the yoke.
Another very common arrangement is the autotransformer shown
in Fig. 17. Here there is one winding to which all taps are made. Tlie
horizontal output tube is connected at point A and the stepped-up
voltage for the high voltage rectifier tube is obtained from point B.
Horizontal deflection yoke coils are connected across points C, D and
E. All of the testing methods just outlined for the isolation horizontal
output transformer are applicable here, too. The boost indicator and
hi voltage still function as before, for the same conditions, and both
are connected as before. The ability of the instrument to check for
continuity can be put to good use here because continuity should
exist between all points on the transformer. If continuity is not ob­
tained, the transformer is open.
In Fig. 17 L-1 serves primarily as a filter coil. If this component
should open, no B+ would be available to the horizontal output tube,
and if L-1 was shorted, the circuit would still operate normally; it is
H.V.
RECTIFIER
HOR I Z.-----t-t
r
osc.
IOK
250V
J
.047
L-1
B+
250V
Figure 17-A Horizontal Output Section using an Auto Transformer type of output transformer
quite possible that considerable RF interference would appear in the
picture. If no interference did appear, there would be no visual in­
dication of a short in L-1. If C-1 should short, the damping tube
would be effectively cut out of the circuit and no boost B+ would be
developed. B+ voltages, however, would appear on the B+ boost line
and at the plate of the horizontal output tube. If C-1 should open,
it would have very little effect on overall operation, although here,
again, RF interference might appear in the image.
Capacitor C-2 is the component receiving the additional voltage
which the damper tube develops. If C-2 should short, no boost B+
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