Kepco Series APH Power Supplies are high voltage, low
current, precision-stabilized d-c sources of approximately
twenty watts of d-c output power. Their important design
a) AUTOMATIC CROSSOVER BETWEEN VOLTAGE AND CURRENT
STABILIZATION MODE OF OPERATION WITH VISUAL FRONT PANEL
(LED) MODE INDICATORS,
b) PRECISION, TEN-TURN FRONT PANEL OUTPUT VOLTAGE AND OUTPUT
c) RECESSED FRONT PANEL OUTPUT METERS PERMIT THE
SIMULTANEOUS MONITORING OF OUTPUT VOLTAGE AND OUTPUT CURRENT.
d) FRONT AND REAR OUTPUT TERMINALS WITH REMOTE SENSING
PROVISION, ALLOW PRECISION STABILIZATION AT A DISTANT LOAD.
e) PROGRAMMING TERMINALS PERMIT ACCESS TO A BUILT-IN,
INDEPENDENT PREAMPLIFIER, TO THE VOLTAGE CONTROL AND MAIN
VOLTAGE AMPLIFIERS AND TO A SEPARATE CURRENT CONTROL
AMPLIFIER. A MODE FLAG SIGNAL OUTPUT (TTL COMPATIBLE), AS
WELL AS TWO D-C REFERENCE SOURCES (±6.2 volts at 1 mA MAX.}
REFERENCED TO COMMON (+ SENSE) ARE PROVIDED.
1-5 The APH Power Supply can, in simplified form, be
electrically represented by the fold-out diagram in Section
III of this manual (see FiG. 3-15 at the end of Section
III). A high voltage, low current d-c source is controlled
by a series pass element (vacuum tube), which in turn is
controlled by the driver circuit via the voltage channel or
the current channel. The driver is connected to three
control amplifiers (Main Voltage, Internal Current Control,
External Current Control) via the gating circuit, which
permits only one amplifier to take control of the APH output.