Tektronix TYPE L Instruction Manual page 15

done with the VARIABLE ATTEN. BAL. con­
tro l, R6812, which adjusts the voltage on the
control grid of V6342, thereby regulating current
through the tube and setting the voltage on
the cathode. The presence of current through
R6352 is easily indicated by
V AR IAB LE con tro l--if current is present its
magnitude w ill be changed by rotation of the
control, producing a shift in the position of
the crt trace.
The V E R TIC AL POSITION control, R6522,
and the Vert. Pos.
provide fo r vertical
beam. Each of these
two potentiometers connected between +225
volts and ground. The center tap of one potentio­
m eter of each control is connected to one
side of the push-pull circuit, and the center
tap of the other is connected to the other
side of the circuit.
wired so that as the voltage on one center
tap increases, the voltage on the other center
tap decreases. Turning
increases the dc level on the grid of one
D rive r Cathode Follow er while
the dc level on the grid of the other D river
C .F . Since the following stages are dc-coupled,
this change in dc level at the D river C.F.s
AA
rotating the
Range control, R6572,
positioning of the crt
controls consists
The potentiometers are
these controls
decreasing
Circuit Description - Type L Plug-In
results in a vertical displacement of the crt
beam.
Minimum capacitive
circuit of the Phase Inverter Stage is assured
by the two sets of cathode followers at the
output--the D river
and the Output Stage C .F .s, V6632 A and B.
Output Cathode Followers
The Output Cathode
low-impedance signal source to drive the circuit
capacitance at
of
socket. This cathode follow er circuit is modified
by the addition of resistors in the plate circuits
and capacitors cross-connected from each plate
to the opposite
im proves the high-frequency balance of the
unit.
The H. F. Peaking control, R6692 in the
cathode circuit of the Output C.F.s varies
the current through these
high-frequency
matches the impedance of the cathode circuits
to the fixed series peaking coils, L6672 and
L6772.
loading to the plate
C .F .s, V6732 A and B,
Followers provide a
the plug-in interconnecting
cathode. This configuration
tubes. F or best
response, this adjustment
3-3