B&K 1076, Инструкция по эксплуатации

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The electrical impulses which have been produced as a result of the light
variation on the photomultiplier tube are developed across the photomultiplier
load resistor R-102 on your schematic. This is a 1000 ohm resistor.
The video signal is capacity coupled to the grid of V-2A. V-2A is the first
video amplifier. In order to improve the high frequency response of the system,
inductive peaking is employed in the plate circuit of this tube and R.C. peak-
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Figure 28-Voltage as Light Beam
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ing is employed in the cathode circuit. In the plate circuit of V-!:!A there is a
500 ohm potentiometer which is part of the plate load resistor of V-.3A. It is
the common coupling between these two stages which mixes the synchronizing
information with the video information to produce a composite signal of both
sync and video. This signal is present at the plates of V-2A. This composite
signal is capacity coupled to the grid of V-3B. Outputs are taken from both
plate and cathode of V-3B and appear on the front panel as the video output,
either sync positive or sync negative, depending upon whether the polarity
reversal switch selects the plate or the cathode circuit. The plate load re­
sistor for V-3B consists of two 470 ohm resistors. The signal present at the
junction of the two resistors is capacity coupled to V-4A which is the R. F.
modulator. The R.F. modulator receives in the cathode circuit the output of
the raido frequency oscillator V-5. Also present at the cathode is the output
from the 4.5 me sound system and the output of the color oscillator. Modula­
tion results in this tube, and the modulated R.F. output is taken from the
plate and is capacity coupled to R-29A part of the R.F. Attenuator network.
It is at this point that the modulated R.F. signal is available on the front panel.
Synchronizing information is obtained by mixing a combination of vertical
and horizontal signals in V-2B. A few turns of wire which form the secondary
of the width coil L-2 provides the cathode return of V-2B. A vertical pulse
from the vertical saw generator is applied to the grid of V-2B through suitable
filtering to remove horizontal pulses. The mixing is accomplished in the plate
circuit of this tube, and at pin 6, the plate, both vertical and horizontal sync
information is present. This is capacity coupled to the grid of V-3A where
additional amplification and clipping of the sync signal is accomplished. Part
of the load resistor of V-3A is common to V-2A. This is the previously men­
tioned 500 ohm control which is the Sync Level Adjust. A potentiometer is
connected from the plate and cathode of V-3A. When the potentiometer is in
its center position it is affectively at signal ground an no output will appear at
the sync output jack. As the potentiometer R-2 is rotated either clockwise or
counter clockwise you will approach either the plate or the cathode signal.
This enables the user to acquire either sync positive or sync negative at the
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