Operating instructions

LOCAL OPERATION
3-8 46882-311D
Rear panel controls and connectors
Fig. 3-3 Rear panel layout, (with optional GPIB fitted)
On the rear panel of the instrument are: -
(20) AC power supply input connector. One range for all mains voltages. See the Performance
data section in Chapter 1. The AC supply fuse is contained within this connector.
(21) DC input voltage selector. Switches the power supply DC input circuits to match the available
supply voltage. Ranges are 11-20 V and 18-32 V.
(22) Power switch. The power switch has three positions ON, OFF, CHARGE. The ON position
connects the power source to the instrument, the CHARGE position allows the Service Monitor
power supply to recharge the accessory battery pack (if connected) from the AC mains supply.
See Getting started; on Page 3-9.
(23) DC supply input voltage connector. For direct connection of optional accessory battery pack
and for powering the instrument from other DC supplies. See Performance data, in Chapter 1.
(24) DC supply pin connection diagram. Shows the polarity of the DC power connector
(25) DC supply fuse.
(26) GPIB interface connector. This connector is only present when the GPIB interface option is
fitted. Connection details are given in Chapter 2, under Remote control connections, GPIB.
(27) GPIB interface unit. Optional. See (26) above.
(28) External frequency standard input. This can be 1, 2 5 or 10 MHz; the Service Monitor will
identify the applied frequency. In the event of external standard failure, control will revert to the
internal standard.
(29) Demodulated signal output. The demodulated signal removed from the input RF signal is
brought to this connector for feeding to external equipment.
(30) EXT MOD IN (External modulation input). A signal applied to this connector can be used as a
modulation source for the receiver test signal. The input level of the applied signal should be
1.00 V (RMS sinewave) in order to maintain the correlation with the modulation level
calibration. The frequency of the signal should be within the range of the internal modulation
source of 20 Hz to 20 kHz (AM), DC to 100 kHz (FM).