Sect. I1 Page 2 Model 618B
I
voltages remain applied to all tubes so that the K. PULSER. TE
-
signal generator may be instantly operative when
The setting of this control determines the pulse
this switch is moved to one of its other positions. r
repetition frequency of the internal pulse generat-
ing circuits when the MOD. SELECTOR switch is
5) INT - When in this position, pulse repetition in the INT, INT. FM or SQ. WAVE position and
frequency is indicated by the position of the the SYNC SELECTOR switch is in either the X1
PULSE RATE control when the SYNC SELECTOR or the X10 position. When the SYNC SELECTOR
switch is in the X1 position. When the SYNC switch is in the X1 position, the pulse repetition
SELECTOR switch is in the X10 position, the pulse rate is as read on the calibrated dial of the control.
rate will be 10 times the rate indicated by the When the SYNC SELECTOR switch is in the X10
calibrations of the PULSE RATE control. position, the reading of the pulse rate control must
be multiplied by 10 to indicate pulse repetition rate.
6) EXT. (+) - When in this position, the signal
generator may be modulated by positive external
pulses or square waves applied to the EXT. MOD.
connector on the front panel.
L. SYNC SELECTOR
7) EXT. (-) - When in this position, the signal This switch determines the type of synchro-
generator may be modulated by negative external nization that is to be employed by thesignal gen-
pulses or square waves applied to the EXT. MOD. erator. It has the following positions:
connector on the front panel.
8) SQ. WAVE - When in the SQ. WAVE position, 1) % - When the switch is in this position, and
the output signal generator will be square waves the MOD. SELECTOR switch is in the INT. position,
of radio frequency voltage. The repetition rate the signal generator may be synchronized by ex-
of these pulses will be determined by the adjust- ternal sine-wave voltages with an amplitude be-
ment of the PULSE RATE control and the SYNC tween 5 and 50 volts rms, applied to the SYNC IN
SELECTOR switch in the X1 or XlOpositionand connector on the front panel.
will be between 40 to 4000 pulses per second. The
rron99 time will be approximately equal to the
2) Em.(-) - When the switch is in this position,
?off? time.
and the MOD. SELECTOR is in the INT. position,
the signal generator must be synchronized by
external negative voltage pulses of an amplitude
between 5 and 50 volts applied to the SYNC IN
I. PULSE WIDTH
connector on the front panel.
The adjustment of this calibrated control de-
termines the width of the main output pulse when
3) En.(+) - When the switch is in this position,
the MOD. SELECTOR switch is in the INT. po-
and the MOD. SELECTOR switch is in the INT.
sition and the SYNC switch is in the EXT. +,
position, the signal generator must be synchro-
EXT. -, ?L , X1 or X10 positions. The width be-
nized by external positive voltage pulses with an
tween is approximately 0.5 (MIN) and 10 micro-
amplitude of between 5 and 50 volts applied to the
seconds, depending on the position of the control.
SYNC IN connector on the front panel.
4) X1 - When the SYNC SEL. switch is in this
J. PULSEDELAY position, and the MOD. SELECTOR switch is in the
INT. position, the internal pulse generator is free-
This control determines the time delay between
running. The repetition rate is as read directly
the start of the synchronizing pulse and the stak
on the PULSE RATE control.
of the radio freuency output pulse delivered by
the signal generator. The control permits in-
sertion of delays from 3 to 300 microseconds fol- 5) X10 - When the SYNC SELECTOR switch is in
lowing the synchronizing pulse. This same delay this position, and the MOD. SELECTOR switch is
period will also be present between the pulse ap- in the INT. position, the repetition rate of the
pearing on the SYNC OUT connector and the synchronizing pulses is as read on the dial of the
DELAYED SYNC OUT connector on the control panel. PULSE RATE control multiplied by 10. |
ACEC
