Kenwood CS-1045, Instruction Manual

Page: 15 / 35

* Internal Sync
When the SOURCE selection is in INT (V.MODE, C H 1 ,
CH2, LINE), the input signal is connected to the internal
trigger circuit. In this position, a part of the input signal fed
to the INPUT (5) or (9) jack is applied from the vertical
amplifier to the trigger circuit to cause the trigger signal
triggered with the input signal to drive the sweep.
When the V.MODE position is selected, the trigger source
is dependent upon the vertical MODE selection.
When the vertical MODE switch is selected in A L T and
DUAL, the trigger source alternates between channel 1 and
channel 2 with each sweep.
When the vertical MODE switch is selected in A L T and TRI,
the trigger source alternates channel 1 thru channel 3 with
each sweep.
This is convenient for checking amplitudes, waveshape, or
waveform period measurements and even permits
simultaneous observation of two waveforms which are not
related in frequency or period. However, this setting is not
suitable for phase or timing comparison measurements. For
such measurements, two or three traces must be triggered
by the same sync signal.
When the SOURCE selection is in C H 1 , the input signal at
the channel 1 INPUT (5) jack becomes trigger regardless of
the position of vertical MODE. When the SOURCE selection
is in C H 2 , the input signal at the channel 2 INPUT (§) jack
becomes trigger regardless of the position of vertical
MODE. If the SOURCE switch is set to the LINE position,
triggering is derived from the input line voltage (50/60 Hz).
This is useful measurements that are related to line fre-
quency.
* External Sync
When the SOURCE selection is in E X T / C H 3 , the input
signal at the E X T TRIG INPUT @ jack becomes the trig-
ger. This signal must have a time or frequency relationship
to the signal being observed to synchronize the display. Ex-
ternal sync is prefered for waveform observation in many
applications. For example. Fig. 7 shows that the sweep cir-
cuit is driven by the gate signal when the gate signal in the
burst signal is applied to the E X T TRIG INPUT jack. Fig. 7
also shows the input/output signals, where the burst signal
generated from the signal is applied to the instrument under
test. Thus, accurate triggering can be achieved without
regard to the input signal fed to the INPUT (5) or (9) jack so
that no further triggering is required even when the input
signal is varied. When the vertical MODE is set to TRI,
triple-trace display is provided and the signal applied to EX-
T / C H S is to be used to trigger the sweep, with INTernal
sync possibility.
Trigger signal
(Gate signal)
CH1 (Input signal to
' amplifier, etc.)
CH2 (Output signal
from amplifier, etc.)
* Coupling
The COUPLING switch selects the coupling mode of the
trigger signal to the trigger circuit according to the type of
trigger signal (DC, A C , signal superimposed on dc, signal
with high frequency noise.).
A C :
Most commonly used position; permits triggering from
10 Hz to over 60 MHz (for C S - 1 0 4 5 , 4 0 MHz). Blocks dc
component of sync trigger signal.
HFrej.:
Attenuates trigger signal above 100 kHz. Useful to reduce
high-frequency noise, and permits triggering from the
modulation envelope of an amplitude modulated rf signal.
DC:
Permits triggering from dc to over 6 0 MHz (for C S - 1 0 4 5 ,
4 0 MHz). Couples dc component of sync trigger signal.
Useful for triggering from very low frequency signals
(below 10 Hz) or ramp waveforms with slow repeating dc.
Waveform with high frequency noise
1 5
Fig.
7
Trigger signal by H F rejection
Fig.
8