10
960 SEQUENTIAL CONTROLLER
24-Stage Operation
The main purpose of the 962 sequential switch module is to alternately select between the 3 output rows of the 960 to create
a 24-stage sequence. Patch the trigger OUT jack from stage 1 into the SHIFT input of the 962. Patch the 3 output rows A, B, C from
the 960 to the 962's 3 SIG inputs. Now the 962's output will be the 24-stage sequencer output, or leave out the C row patch cable
for 16 steps.
Tuning Procedure
1.
Power up the 960 module and press the OSC ON button. Allow the unit to warm up for a few minutes.
2.
Prepare the following control settings:
a. Set the 3RD ROW CONTROL OF TIMING switch to off.
b. Set the FREQUENCY rotary switch to 6 on the scale.
c. Make sure no jack is connected to the oscillator CONTROL INPUT.
3.
Set the FREQUENCY VERNIER for exactly 100 Hz at the OSCILLATOR OUTPUT measured
with an accurate frequency meter and adjust the DUTY CYCLE ADJ for 90% duty cycle.
4.
Fine-tune the 960 oscillator's high frequency scaling as follows:
a. Apply exactly +2.0 VDC to the CONTROL INPUT jack (A 921A module can be used
to supply the +2.0 VDC or use a similar low-impedance stable-voltage source).
b. Trim the 960 SCALE ADJ trimmer to set 400 Hz, then remove the +2.00 V input
and readjust the 960 FREQ VERNIER to 100 Hz.
c. Repeat this cycle until both 100 Hz and 400 Hz are accurate to ±1 Hz when the +2.00 VDC
is plugged in and out of CONTROL INPUT jack.
OUT TO
5.
Fine-tune the 960 oscillator's low frequency scaling as follows:
ANOTHER
MODULE
a. Apply exactly -2.0 VDC to the CONTROL INPUT jack (A 921A module can be used to supply
the -2.00 VDC or use a similar low-impedance stable-voltage source).
b. Trim the 960 LOW END ADJ trimmer to set 25 Hz, then remove the -2.00 V input
and readjust the 960 FREQ VERNIER to 100 Hz.
c. Repeat this cycle until both 100 Hz and 25 Hz are accurate to ±1 Hz when the -2.00 VDC
is plugged in and out of CONTROL INPUT jack.
6.
Set the 960 oscillator's maximum high frequency as follows:
a. Make sure no jack is connected to the CONTROL INPUT.
b. Set the FREQUENCY VERNIER fully clockwise (10 on the scale).
c. Adjust the FREQUENCY ADJUST trimmer to set exactly 500 Hz at the OSCILLATOR OUTPUT.
d. Apply exactly +2.0 VDC to the CONTROL INPUT jack (this may stop the oscillator running).
e. Adjust the FREQ STOP ADJ trimmer until the oscillator starts running and set
the maximum frequency to around 550 Hz.
f. Disconnect the +2.0 VDC CONTROL INPUT and check the oscillator frequency is 500 Hz.
Adjust the FREQUENCY ADJUST trimmer if required.
g. Apply exactly +2.0 VDC to the CONTROL INPUT jack, if the oscillator stays running,
the trimming is completed. If not, repeat as required.
11
Quick Start Guide