Racal Instruments 9916 User Manual

-24 Volt Supply
4.59 The 1 MHz signal from 1C4/6 is used to clock IC14o. This is connected to divide
by two, so that 07 is driven at 500 kHz, The oscillation in Tl is rectified by 06
-_md D7, and boosts the +5 vo! ts to +24 vol ts to supply IC26. The supply is present only when
the 'A' Channel is selected as in other conditions IC14a is held in the cleared state.
-~1-2 Volt Supply
4.60 A +2 volt supply is obtained for IC4 from the -+5 volt supply via the regulator 014.
Q14 is controlled by 015, which obtains its reference voltage from IC4/11.
Battery Charg ing
4.61 If fitted, the batteries receive trickle charge whenever the instrument is
operating from a Iine power supply. Each battery is connected between the -+5
-volt and -5 volt rails, as shown in Fig. 4.2. The diodes D26 and D27 prevent the batteries
discharging if the supply is disconnected with the instrument switched on.
+ 5V RAIL
'I BATTERY 'A'
I + 5V
o
l(
WITCH
52
LINE POWER
CHARGE
~
52e
027
R74
BATT 0
POWER
RI3B
7 BATTERY'S'
I -5V
o
-5V RAIL
026
R128
S2d
4
~_~_----,-3-e S29
, 12
fvS5I
CI01
"W~GA~~ EM ITTER
R133
5
o
Battery Charging Circuit
Fig.4,2
4-10
9916 Vol. 2

Racal Instruments 9916 Specifications

General

Brand	Racal Instruments
Model	9916
Category	Measuring Instruments
Language	English