Table of Contents
Advertisement
In the second stage, the right-hand section of
dual triode VIZ acts as a cathode follower to
increase the signal on the grid of the left-
hand section.
The plate circuit in the left-
hand section supplies the bias for the grids
of the series regulator tubes. The plate cir-
cuits of the two sections of VIZ are cross-
coupled. This arrangement results in great-
er amplifier gain and sensitivity.
To ensure that the series regulator tubes will
have sufficient conductivity to maintain regu-
lation under transient conditions, a separate
screen voltage supply from selenium recti-
fier SRI is provided for the regulator tubes.
The voltage divider in the voltage compari-
son circuit provides separate paths to the
signal grid of dual triode V13 for high-fre-
quency and low-frequency voltages. to make
the response of the regulated supply fast at
high frequencies and yet very stable.
At a-
bout 1, 000 cycles, AC components are cou-
pled to the grid via resistor R38 and capaci-
tor C4.
DC components pass to the grid
through a resistor network (R38, R39, R40,
R4l) •
3-3
3-3 BIAS SUPPLY CIRCUIT
Arrangement and operation of the regulated
bias supply circuit is similar to that of the
plate voltage supply circuit except that pri-
mary current to the bias supply transform.er,
T3, is not variable.
The bias supply series
regulator tube, V8, is controlled by a differ-
ential amplifier (dual triodes VlO and V9).
The comparison voltage for the circuit is
furnished by voltage reference tube VII, and
the sample voltage is sampled with respect
to COM
th~ough
a voltage divider which in-
cludes variable resistor RZ4. The fixed bias
voltage is brought out to binding post -300V
50 MA on the control panel.
A variable bias voltage is available at bind-
ing post 5 MA. The voltage level of the vari-
able bias supply may be adjusted by means of
the -BIAS CONTROL knob on the front panel.
The control varies the setting of variable re-
sistor R46 in the voltage divider across the
bias supply output circuit.
Advertisement
Table of Contents
