Philips PM3320 Operating Manual page 39

4-19E
VERTICAL COUPLING MENU
After pressing pushbutton VERTICAL COUPLING, the VERTICAL
COUPUNG menu for channel A and channel B is displayed and
the input coupling for hese channels can be selected.
VERTICAL
COUPLING A
AC DC 4
GROUND 2
1MQ 500 3
OFFSET > 4
COUPLING B
AC DC ba
GROUND 6
1MQ 500 7
OFFSET > 8
1 AC DC (channel A)
With this softkey a selection can be made between AC. input coupling and DC input
coupling. Pushing this sottkey changes the selection from AC ta DC or reverse, the active
selection is displayed intensified.
If AC is selected, the offset becomes 0 Volt.
lf DC is selected, the previously selected offset value is active again.
2 GROUND (channel A)
With GROUND selected, the connection between the input socket and the relevant input
circuit is interrupted and the input circuit is grounded.
3 1 MOhm 50 Ohm (channel A}
With this softkey, a selection can be made between an input impedance of 1 MOhm or an
input impedance of 50 Ohm.
\fa probe with automatic probe indication is used, the oscilloscope automatically switches
to the correct impedance. No other selection can be made then.
If an input voltage higher than 5 V de and ac r.m.s. is applied to the input socket and 50
Ohm is selected, the instrument does not switch to 50 Ohm and a message
Unsafe condition for 50 Ohm to be switched on.
input impedance not changed.
is displayed.
lf50 Ohmis on and an input voltage between 5 V de andacr.m.s.and 25 Vdcandacr.ms.
is applied to the input socket, the instrument will automatically switch to 1 MOhm input
impedance {without warning).