TM 9-4935-481-14-1
(5) Trigger pulse simulator. The output of the trigger pulse simulator section is a square wave whose amplitude
The missile command mode increases the available output voltage to a range of approximately +2.86 Vdc to +6.46 Vdc.
and pulse width are controllable in the manual mode, or fixed at a go or no-go level for checkout of the TTS trigger
When it is desired to adjust the dc level control for a fixed amount of bias, the ripple potentiometer must first be adjusted to
evaluation circuits.
the fully ccw position. This makes the ripple component equal to 0, so that only the dc level is being measured.
(a) Trig output switch S15 selects a fixed go level pulse, or one of two pulses with no-go characteristics.
(b) The ripple control determines the peak amplitude of the 20 Hz square wave that is summed with the
The manual and read positions enable amptd (volts) potentiometer R6, and width (ms) thumbwheel switch S16.
dc bias discussed above. Maximum available amplitude is independent of test mode and fixed at approximately 843 mVP.
Internal test position 3 stops the ripple so that the positive peak may be measured and adjusted as a dc voltage. For
(b) The pulse must be initiated by trigger switch S14. After selection of the test mode or the pulse
example, if the dc level was first set (per (a) above) to +3.000 Vdc, the ripple control could then be adjusted so that the DMM
parameter (if manual), momentary actuation of S14 will result in a single pulse being generated. The exception to this is if
read +3.500 Vdc, thus resulting in a 0.500 VP ripple about +3.000 Vdc when the internal test switch was returned to off. (The
the trig output switch is in the read position, in which case the signal will remain in the "high" state to permit adjustment of the
low side of the ripple component may also be checked by internal test position 2, in which case the DMM reading would be
amplitude by R6.
+2.500 Vdc.).
(c) The counting dial of amptd(volts) R6 is a direct readout of the manual pulse amplitude; i.e., a setting
(4) Vertical wire simulator. Characteristics of the vertical wire pulse train may be controlled by amptd(volts)
of 200 will result in an approximate +2.00 VP pulse. If greater accuracy is required, the read position may be used, as
potentiometer R9 and the period(ms) and width(ms) thumbwheel switch S22. +DC/pulse/-dc switch S23 determines whether
described above. Maximum pulse amplitude is limited to +5.0 VP above a OV baseline.
the vertical wire output will be a simulated wire clamp dc voltage or a series of pulses.
(d) Manual pulse width is set by width(ms) switch S16. A minimum of 2.0 msec to a maximum of 13.9
(a) In the +dc position of S23, the vertical wire output becomes a positive voltage whose amplitude is set
msec, in 0.1 msec increments, is available.
by R9 between the limits of O to approximately +1.05 Vdc. Similarly, in the -dc position, the output can be adjusted between
O and -1.05 Vdc, while the pulse position selects the output from the pulse-generating circuits.
(6) Rate simulator. Rate simulator horiz and vert potentiometers R8 and R7, respectively, adjust the amplitude
of the pulse that is used as the manual rate/ position stimuli. The pulse is initiated by pulse switch S17, and appears at the
(b) The width(ms) section of S22 allows the pulse width to be set between 2.0 and 13.9 msec, in
output of both the horizontal and vertical channels. The pulse generation logic is driven by a 20 Hz square wave, so that the
increments of 0.1 msec. The period(ms) section controls the pulse repetition time (PRT) of the signal over a range of 3.0
output pulse width is precisely 50 msec. Although the pulse logic is common to both channels, amplitude is adjusted
msec (usable minimum) to 999.9 msec, in increments of 0.1 msec. The period and pulse width may both be changed while
independently, thus allowing, for example, a +5.0 VP pulse in one channel and a -3.0 VP pulse in the other channel.
the pulse is being generated; however, the first pulse delay of 708 msec occurs only with respect to actuation of the test start
Amplitude of the pulse is variable between approximately +9.0 VP and -9.0 VP. Since no method exists for stopping the
switch.
pulse in its "high" state, the amplitude must be set by monitoring the dc reference established by each potentiometer. The
horizontal channel reference may be read on selector A position G13, while the vertical reference is on selector A position
(c) Amplitude of the pulses is set by the amptd (volts) potentiometer in the manner described in (l).(e).5.
G14.
above, over a range of O to approximately 10.50 VP.
f.
Support Functions.
When operating with the TTS, the vertical wire signal looks into an impedance of 15Ks (input resistance of an inverting op
amp). Since the output impedance of the simulator is 50, a voltage divider effect is present and must be considered when
adjusting or measuring the signal amplitude. A load of 15K is placed on the simulator output by position 7 of the internal test
(1)
Counter inhibit. Since many DMS-D signals are time-sequenced, it is
switch, so that when the TTS is not connected the loading effect may be duplicated.
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