Hameg HM 407A Manual Download Page 14

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Subject to change without notice

must be performed twice. At first

REFERENCE

memory

I must be displayed and then overwritten. Then

REFE-

RENCE

memory II must be chosen and overwrittten.

Attention!
As the reference signal is stored and displayed in the
same position as the current signal, it is not immediately
noticeable in most cases.

(12) SAVE / RECALL

- Pushbuttons.

The instrument contains 9 non volatile memories. These
can be used by the operator to save instrument settings
and to recall them. This relates to all controls which are
electronically selected.

SAVE

Press the

SAVE

pushbutton briefly to start the save

procedure. The readout then indicates the letter “S”
followed by a cipher between 1 and 9, indicating the
memory location. If the instrument settings stored in this
memory location must not be overwritten, briefly press
the

SAVE

or the

RECALL

pushbutton to select another

memory location. Each time the

SAVE

pushbutton is

briefly pressed the memory location cipher increases
until the location number 9 is reached. The

RECALL

pushbutton function is similar but decreases the memory
location cipher until 1 is reached.

Press and hold SAVE for

approx. 3 seconds to write the instruments settings in the
memory.

RECALL

To recall a front panel setup, start that procedure by
briefly pressing the

RECALL

pushbutton. The readout

then indicates the letter

“R”

and the memory location

number. If required, select a different memory location as
described above. Recall the settings by pressing and
holding the

RECALL

pushbutton for approx. 3 seconds.

Attention:
Make sure that the signal to be displayed is similar to
the one that was present when the settings were
stored. If the signal is different (frequency, amplitude)
to the one during storage then a distorted display may
result.

If the

SAVE

or the

RECALL

pushbutton was depressed

inadvertently, briefly press both pushbuttons at the same
time or wait approx. 10 seconds without pressing either
pushbutton to exit that function.

The setting controls and LED’s for the Y amplifiers,
modes, triggering and time base are located underneath
the sector of the front panel described before.

(13) Y-POS. I

- Control knob.

The vertical trace position of channel I can be set with this
control knob. In

ADD

(addition) mode both (

Y-POS. I

and

Y-POS. II

) control knobs are active. If the instrument is

set to analog XY mode this control knob is inactive and the

X-POS.

knob must be used for a horizontal position shift.

If automatic triggering

(AT)

is present and the input is set

GD (33)

, the vertical trace position corresponds with 0

Volt (reference) at the input and can be set to any suitable
position. In

ADD

mode these conditions apply to both

channels. After switching

off and selecting DC input

coupling it is possible to determine the DC content of a
signal by comparing the actual Y position with the
previously determined 0 Volt Y position.

Y-POS. I Symbol

Provided that the readout is displayed and

”DC REF = ON”

is selected in the

”SETUP”

submenu

”MISCELLANEOUS”

the 0 Volt reference position is indicated by a ground ( )
symbol. For channel I this symbol is displayed on the left
of the vertical (graticule) center line, if the Y-POS. I trace
position is set within the screen. This allows you to
determine the 0 Volt reference position at any time.

Attention!
In XY mode the 0 Volt reference symbol is automatically
switched off.

STORAGE MODE ONLY

mode the

Y-POS. I

knob is operative as the

position

control and the

X-POS.

knob is inactive.

The

Y-POS. I

knob can be used for shifting the position