Hameg HM 1004-3 Series, Руководство пользователя

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Subject to change without notice
18
Controls and Readout
in triggered delay mode. In this mode, the former A
timebase trigger settings regarding the trigger mode
(automatic or normal), -coupling, -slope and -level set-
tings are stored but still active. With the activated delay
trigger the instrument is automatically set to normal
trigger mode and DC trigger coupling for the B timebase.
As the instrument contains a separate trigger unit for the
B timebase, the trigger level and slope can be set
independently using the same controls used for the A
timebase trigger setting. The trigger point is indicated
again but has the added letter B in the readout.
In delay trigger mode, the delay time must first elapse.
Then the next suitable signal slope (direction and height)
starts the B timebase. If those basic requirements are not
met, there will be no B trace visible. Under the condition
that the signal contains several suitable slopes after the
delay time, it can be seen in alternate timebase mode that
the delay time setting (DEL. POS.) now causes the
intensified sector to jump from one slope to the other.
VAR.:
Pressing and holding the DEL.TRIG. - VAR. pushbutton
selects the TIME/DIV. (24) control knob function be-
tween timebase switch and vernier (variable). The cur-
rent setting is displayed by the VAR-LED located above
the knob.
The variable function can be activated for the A timebase
or the B timebase, the settings are stored separately. As
alternate timebase mode is a B timebase sub mode, only
the B timebase is affected in this condition.
A Timebase.
After switching the VAR-LED on, the time deflection
coefficient is still calibrated until further adjustments are
made. Turning the
TIME/DIV. (24) control knob counter
clockwise increases the time deflection coefficient (re-
duces the deflection speed) and the deflection coefficient
becomes uncalibrated. Instead of e.g. “A:10µs”, the
readout then displays
“A>10µs” indicating the uncalibrated
condition. This setting is stored if the instrument is
switched to alternate (A and B) or B timebase mode.
Pressing and holding the DEL.TRIG. - VAR. pushbutton
again in A timebase mode switches the LED off, the
timebase switch function on, and sets the time deflection
coefficient back into the calibrated condition.
B and Alternate Timebase.
In alternate (A and B) as well as in B timebase mode,
pressing and holding the
DEL.TRIG. - VAR. pushbutton
selects the TIME/DIV. knob function between B timebase
switch and B vernier (VAR -LED on). In the latter case the
TIME/DIV. knob can be used in the same way as de-
scribed before under A timebase condition.
Underneath the front panel sector described above,
the BNC sockets and four pushbuttons are located.
(27)INPUT CH I - BNC socket.
This BNC socket is the signal input for channel I. In XY
mode, signals at this input are used for the Y deflection.
The outer (ground) connection is galvanically connected
to the instrument ground and consequently to the safety
earth contact of the line/mains plug.
(28)AC / DC - Pushbutton with two functions.
Input coupling:
Briefly pressing this pushbutton switches over from AC
(
~ symbol) to DC (= symbol) input coupling and vice versa.
The setting is displayed in the readout with the deflection
coefficient.
Probe factor:
Pressing and holding the pushbutton selects the indi-
cated deflection coefficient of channel I displayed in the
readout, between 1:1 and 10:1. In condition 10:1 the
probe factor is thus indicated by a probe symbol displayed
by the readout in front the channel information (e.g.
“probe symbol”, Y1...). In the case of cursor voltage
measurement, the probe factor is automatically included.
Please note:
The symbol must not be activated unless a x10 (10:1)
attenuator probe is used.
(29)GD - INV. - Pushbutton with two functions.
GD:
Each time this pushbutton is pressed briefly, the input is
switched from active to inactive and vice versa. It is
displayed in the readout as an earth (ground) symbol
instead of the deflection coefficient and the
~ (AC) or =
(DC) symbol.
The GD setting disables the input signal, the AC/DC (28)
pushbutton and the VOLTS/DIV (16) knob. In automatic
trigger mode the undeflected trace is visible representing
the 0 Volt trace position.
The ”0 Volt” position is indicated by a ”
⊥
” symbol in the
readout. Please note Y-POS. I (9) .
INV.:
Pressing and holding this pushbutton switches the chan-
nel I invert function on or off. The invert
“on” condition
is indicated by the readout with a horizontal bar above
“Y1” (Yt mode) or “Y” (XY mode). The invert function
causes the signal display of channel I to be inverted by
180°.
(30)Ground socket - 4mm banana socket
galvanically connected to safety earth.
This socket can be used as reference potential connec-
tion for
DC and low frequency signal measurement
purposes and in COMPONENT TEST mode .
(31)INPUT CH II - BNC socket.
This BNC socket is the signal input for channel II. In XY
mode, signals at this input are used for the X deflection.
The outer (ground) connection is galvanically connected
to the instrument ground and consequently to the safety
earth contact of the line/mains plug.
(32)AC / DC - Pushbutton with two functions.