Philips PM 6611 - Operation; General Information; Switch on Power; Warm up Time

VI. OPERATION
Figures VI-1 to VI-4.
General Information
1. Switch on power
1.1. Mains
Before connecting the counter to the mains check that
the mains transformer is wired for the local mains volt-
age. Refer to chapter IV; INSTALLATION.
Set switch MAINS EXT.BATT./INT.BATT.ON to posi-
tion MAINS EXT.BATT. ©.
Connect mains cable to the counter at @.
Turn DISPLAY TIME control @ to ON. Check that
GATE lamp ® and display are on, indicating that
power is on.
1.2. External battery
Set switch MAINS EXT. BATTERY/INT. BATT. ON ©
to position MAINS EXT.BATTERY.
Connect the cables from the external battery to sock-
ets EXT.BATT. 12—24 V “+” @ and “—” O.
Check that GATE lamp and display are on, indicat-
ing that power is on.
1.3. Internal battery PM 9673
Set switch MAINS EXT. BATTERY/INT. BATTERY
ON ® to position INT.BATTERY ON.
Check that GATE lamp @ and display lights indicating
that power is on. Blinking display indicates low volt-
13
ages. Refer to manual PM 9673 for charging instruc-
tions.
2. Warm up time
The warm up time from the moment of mains connec-
tion is less than 7 minutes to an oscillator error of
less than 10-7 for instrument equipped with the oven-
enclosed oscillators PM9679 or PM 9690. Instru-
ments equipped with the oscillators PM 9677 or
PM 9678 (TCXO) äre ready for use at the moment of
mains connection. Normally the instrument is switched
on from the STAND BY @ position. If so, no warm
up time is needed, irrespective of which oscillator is
employed.
3. External frequency standards
House standards or other frequency standards can be
used instead of the internal 10 MHz oscillator. If a
time resolution of 100 ns is required, 10 MHz must be
used.
When using 1 MHz instead of 10 MHz the decimal
point must be shifted one step to the left to interpret
the display correctly. To set the counter to external
standard the top cover must be removed and jumper
SK 131 Q set to position EXT.