10
Sweep Out
The SWEEP OUT socket provides a 0V to 6V ramp from 600
Ω
impedance to drive the X-input of
an oscilloscope or chart recorder. Terminating this output with a resistor will reduce the output
amplitude. Terminating with 600
Ω
will halve the output giving 0V to 3V.
Holding in the SET STOP button holds the ramp at the maximum and can therefore be used to
set full scale on the oscilloscope or chart recorder.
Note that when the SWEEP OUT is used to drive the X-input of the oscilloscope, the oscilloscope
should be set to DC coupling and not AC coupling which will cause a double image at slow
sweep speeds.
Sweep Rate
The generator sweeps both up and down at the speed set by the RATE control, i.e. it does not
reset rapidly after the upward sweep. This has the advantage that the suitability of the selected
sweep time can be continuously monitored.
Amplitude Modulation (TG230 only)
Depressing the AM ON/OFF button selects AM. The depth of modulation can be adjusted over a
0% to 100% range using the modulation control. When AM is selected the output amplitude will
drop to 50% at 0% modulation.
With the EXT/INT button out, the modulation source is an internal 400Hz sinewave oscillator.
With the EXT/INT button in, external modulation is selected and the AM/SWEEP IN input
becomes the AM input. If a signal is now applied with no DC offset, or if it is AC coupled,
amplitude modulation of the generator output is achieved. A 2V peak-to-peak signal gives
approximately 100% modulation with the modulation control at maximum. Modulating the
generator with a squarewave gives step changes in the output amplitude which are suitable for
testing signal compressors and automatic gain controlled circuits.
Applying a DC offset of approximately -1V gives suppressed carrier modulation. The DC offset
should first be adjusted to suppress the carrier, and the modulating signal then applied.
Applying greater than -1V will invert the MAIN output with respect to the AUX output.
Maintenance
The Manufacturers or their agents overseas will provide a repair service for any unit developing a
fault. Where owners wish to undertake their own maintenance work, this should only be done by
skilled personnel in conjunction with the service manual which may be purchased directly from
the Manufacturers or their agents overseas.
Cleaning
If the instrument requires cleaning use a cloth that is only lightly dampened with water or a mild
detergent.
WARNING! TO AVOID ELECTRIC SHOCK, OR DAMAGE TO THE INSTRUMENT, NEVER
ALLOW WATER TO GET INSIDE THE CASE. TO AVOID DAMAGE TO THE CASE NEVER
CLEAN WITH SOLVENTS.