Patch Panel Description
operational amplifiers . . . Eight high gain,
single ended, inverting amplifiers are brought out to the panel for traditional
analog computer patch cord programming. GP-6 amplifiers feature high gain,
high input and low output impedance, low temperature drift, sufficient output
current to drive general purpose program loads, 6 db/octave roll-off characteristics
to assure stable and repeatable operation under widely varying resistive/capacitive
input and feedback conditions.
Color coding: red, amplifier outputs; gray, summing junctions.
summer integrators . . . Amplifiers 1 thru
4 have internal FET electronic switch networks that create SJ and SJ', the
two summing junction paths required for an integrator's initial condition
and operate modes. (Logic patched to the SW jacks control the switches.)
Networks of summing resistors and integrating capacitors enable patch cords
to program amplifiers as either summers (resistor feedbacks) or summer/integrators
(capacitor feedbacks.) As integrators, output voltages equal the inverted
integral of the sum of the input voltages (plus/minus the initial condition)
where the integration rate is the reciprocal of the R*C time constant. (A
combined "1" input resistor and "B"feedback capacitor
equals a nominal one second.)
When programmed as an integrator, SJ becomes the "operate"
summing junction and SJ' the "initial condition" summing junction.
In the IC mode, when SJ' conducts, the amplifier is programmed as a unity
inverter with the IC jack the input. The integrating capacitor is charged
to the output voltage so that with the IC to OP mode change, integration
starts with the output voltage. In the HD mode, the SW logic voltage is
forced to the "hold" state, the input resistor network is electronically
disconnected from the SJ summing junction and the output is held until released.
GP-6 integrators employ a three state logic: ground or positive for the
IC mode; less than 5 volts for the OP mode; between minus 2 and 3 for the
HD mode.
Color coding: red, amplifier outputs; green, resistor and IC inputs;
gray, summing junctions.
summer amplifiers . . . Absence of SW control
patching latches the SW logic into the SJ conducting state. A resistor patched
as feedback programs a summer. (Amplifiers 1 thru 4 may use the initial
condition network as the resistor feedback and an additional resistor as
an input by patching jacks SJ to SJ'.) The summer output voltage equals
the inverted sum of inputs where input gains are the ratios of the feedback
to input resistors.
Resistors may also be externally connected. Comdyna offers special module-plugs
to add inputs or special non-standard resistor values.
Color coding: red, amplifier outputs; green, resistor and IC inputs;
gray, summing junctions.
inverters . . . Amplifiers 7 & 8 apply internal
input and feedback resistors (summing junctions not brought to the panel)
for use only as gain one, sign inverters.
Color coding: red, amplifier outputs; green, inputs.
coefficient potentiometers . . . Potentiometers
are used primarily for entering parameters (constants) into a program. Pots
1 thru 6 are programmed as grounded attenuators, 7 and 8 as ungrounded voltage
dividers. As attenuators, inputs (top jacks) are multiplied by "settings,"
(adjustments between 0 and 1.0) and terminated as wiper outputs (bottom
jacks.) As voltage dividers, the wiper voltages (middle jacks) are the "settings"
times the differences between the top and bottom jack voltages.
Color coding: yellow, inputs, wipers and bottoms.
multiplier/dividers . . . Multiplier networks
may be programmed for multiplication and/or division of two analog variables.
Multiplication of X and Y inputs occurs when the network is patched to an
amplifier summing junction and the feedback is a resistor. Division of U
by X occurs when the network is patched to the summing junction, the X input
is patched as the feedback, the denominator is patched to the Y input and
the numerator U to an input resistor.
Color coding: brown, inputs; gray, network summing junction.
positive/negative 10V REFERENCE . . . A precision,
positive and negative 10 volts reference provides a "unity" needed
for entering voltage constants.
Color coding: red, plus 10 volts; yellow, minus 10 volts.
Operator Panel Descriptions
OVERLOAD INDICATOR . . . A light alarm glows
when any of the eight patch panel amplifier exceeds an overrange output,
approximately plus/minus 10 volts.
DIGITAL VOLTMETER . . . The DVM displays coefficient
potentiometer settings, the static values of amplifier outputs and positive/negative
reference.
COEFFICIENT POTENTIOMETERS . . . Eight
coefficient potentiometer knobs adjust the input/output settings. Settings
are displayed by the digital voltmeter in the POT SET mode.
Y/POT ADDRESS & X ADDRESS . . . Two
rotary switches enable amplifier outputs and potentiometer wipers to be
selected for digital voltmeter readout or output to an X-Y monitor such
as an X-Y oscilloscope or X-Y plotter.
MODE CONTROL . . . Analog computer simulations
may be conducted in either a slow time or high speed repetitive operation
output. In slow time, the operator depresses the IC, HD and OP pushbuttons
to place a simulation into the reset, hold or run mode. Depressing the RO
(repetitive operation) button speeds system integrator time constants by
400 and repeats the reset and run modes at rates up to 33 per second for
viewing by an X-Y oscilloscope.
The MODE SELECTOR switch is positioned to POT SET for potentiometer setting
and other check-out operations. Otherwise the switch is set to OPR.
POWER & COMPUTE TIME . . . In addition
to power on/off the COMPUTE TIME switch serves also to adjust the compute
time or integrate period in a range of 10 to 100 scaled seconds. The time
base ramp may be selected the X ADDRESS switch, TIME position, to be the
XY plotter or oscilloscope horizontal axis. | 