Global Specialties PB-503, Руководство пользователя

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inputs. Connect the other speaker input to the ground terminal (or one of the
connectors on the ground bus strip). Switch the function generator range switch to
“1” and the Hz/kHz switch to “kHz”. Move the frequency control all the way to the top.
Move the amplitude control upward until you hear a tone coming from the speaker.
Switch the waveform selector to select sine, square, and triangle. A changing but
clearly audible tone should be heard in each position. Changing the position of the
frequency control should vary the pitch of the tone.
If an oscilloscope is available, you may check the function generator for proper
waveform and frequency using standard measurement techniques.
The debounced pushbuttons can be checked by connecting one side of a resistor
(20Ω to 100 KΩ) to +5 volts and the other side to PB1-1, the NC point. Then connect
PB1-1 to LED-1 with the Logic Ind5/+V switch in the +5 position, the red
LED should light when PB1 is pressed and the green LED should light when PB1 is
released. Next, move the connections from PB1-1 to PB1-2, the NO point. Now the
red LED should be lit when PB1 is not pressed, and the green LED should be lit when
PB1 is pressed. Repeat these steps to test PB2.
The logic switches can be tested by connecting the output of logic switches 1 through
8 to the input of logic indicators 1 through 8. Switch the logic 5V/+V high
level switch to +5, and switch the logic ind5/+V operating voltage switch to +5.
Select the CMOS position on the logic indicator TTL/CMOS threshold select switch.
Now the logic indicators should reflect the conditions of the logic switches, that is, red
LEDs will indicate switches in the high (logic “1”) position and green LEDs will indicate
switches in the low (logic “0”) position. Move each switch between its high and low
position to verify proper functioning. Switch the logic 5/+V high level switch
to +V and the logic ind5/+V operating voltage switch to +V; the relationship
between the switch positions and the logic indicator display should remain the same,
regardless of the setting of the 1.3 - 15 volts +V supply.
By using an ohmmeter, you can check the potentiometers. To do so, select an
appropriate range for measuring 10 KΩ and connect the ohmmeter leads to R1-1
and R1-2. With R1 rotated fully counterclockwise a reading of 0Ω ohms should be
observed. As the potentiometer is rotated clockwise, the resistance reading will be
seen to increase linearly up to 10 KΩ ± 20%. Now move the ohmmeter lead from R1-l
to R1-3; with R1 fully clockwise the ohmmeter will read zero ohms, and the resistance
will increase linearly to the full value noted previously as the potentiometer is rotated
counterclockwise. Select an ohmmeter range appropriate for 1 KΩ and repeat these
steps on R2 to verify its function.
To test SPDT switch S9, put S9 in the up position and connect an ohmmeter to S9-1
and S9-2. The ohmmeter should read 0 Ω. When the switch is brought to the down
position, an open circuit should be indicated. Move the ohmmeter lead from S9-1 to
S9-3 and observe a short circuit with S9 down, and an open with S9 up. These steps
can be repeated on S10 to test its functions.