Calibration Menue; I Amplifier; Ii Amplifier; Trigger Amplifier - Hameg HM1004 Service Manual

17) Calibration Menue.

Note: The oscilloscope must first be switched to the adjustment mode for the next 12 points.
Switch the oscilloscope OFF.
Switch the oscilloscope ON.
Press and hold the AUTO SET pushbutton after the HAMEG Logo appears.
Release the AUTO SET pushbutton after the Calibration Menue is on screen.
For error messages see 35).
18) CH I Amplifier
CH 1 AMP is highlight, press CURSOR ON/OFF pushbutton.
Oscilloscope is „working".CH 1 amplifier will be now adjusted.
19) CH II Amplifier.
press Cursor Down pushbutton once.
CH 2 AMP is highlight, press CURSOR ON/OFF pushbutton.
Oscilloscope is „working".CH 2 amplifier will be now adjusted.

20) Trigger Amplifier.

press Cursor Down pushbutton once.
TRIGGER-AMP is highlight, press CURSOR ON/OFF pushbutton.
Oscilloscope is „working".Trigger-amplifier will be now adjusted.

21) R4481: A-Sweep Start Position.

Press Cursor Down pushbutton once.
SWEEP-GENERATOR is highlight, press CURSOR ON/OFF pushbutton.
Locate and identify R4481 (21) on MB-Board.
Set A-time base to 200µs/div.
Press A/ALT/B once, set B-time base also to 200µs/div.
Turn DEL.POS left until Dt:39.0µs in display shows.
Adjust R4481 (21) the dim A-trace 2mm before the bright B-trace.

22) R4430: B-Sweep Start Position.

Locate and identify R4430 (22) on MB-Board.
Adjust R4430 (22) to the beginning of A-trace on left side.

23) R4841: X-Gain x1.

Locate and identify R4841 (23) on MB-Board.
Adjust R4841 (23) for 10.2 div sweep length.

24) A-Time Base Adjustment.

Note: Now the adjustment mode is present. Any change of the VAR. 2.5:1 knob in the
TIME/DIV. section of the front panel causes a new adjustment of the selected time
coefficient. After the TIME/DIV. setting was changed, the adjustment is stored.
Remark: The horizontal center line of the graticule must be used for the reading to avoid
uncertainties due to deflection unlinearities. The manual contains a list of frequencies which
must be used for the different time base settings if a sine wave generator is used for
adjustment purposes. For a high accuracy use the zero (voltage) crossing of a sine wave signal
for the reading.
Set time mark generator to 20 MHz (0.05µs/period) and connect the signal to CH I input.
Set input attenuator CH I to a suitable setting for a signal display of approx. 4 divisions height.
Press both NORM pushbuttons briefly for normal triggering mode.
Turn TRIG. LEVEL knob for exact triggering.
Set time base to 0.05µs/div.
Subject to change without notice 51