6
If connecting to a PC, observe the following connection requirements, use a straight RS232 lead
(avoid null modem leads, these will not operate):
SDU5500 9-pin
PC 9-pin
PC 25-pin
2
2
3
3
3
2
5
5
7 GND
7
7
4
8
8
5
The SDU5500 is fully controllable by PC via the built-in RS232 interface, this includes all keyboard
operations and down loading of the displayed data.
Communication parameter
Data length
8 bit
Parity bit
None
Stop bit
2 bit
Baud rate
9600
Flow control
X flow
4 RF IN (Intermediate Frequency input socket)
The IF output (10.7 MHz) from a suitable receiver such as the AR5000 should be connected to this BNC
input socket using a 50 OHM patch lead constructed of quality coaxial cable such as RG58/U, UR43,
UR76 etc.
(3) LCD, keys, legends & menus
3-1 Description of LCD legends
The LCD is effectively split into three main sections, the top operating environment, the middle spectrum
trace and the bottom menu selection. A total of 17 specific LCD areas are employed:
Top legends
The top of the LCD provides operational information, a summary is as follows:
CF
Centre Frequency (frequency at the middle of the graticule) in MHz.
RBW
Resolution Band Width, sampling resolution 5kHz / 30kHz.
RX
Type of companion radio configured.
FDIR
Frequency sweep direction (ignore unless set to ‘Other’ companion radio type).
STEP
Receive tuning step in kHz.
ATT
Companion radio attenuator status On/Off (cannot accommodate 0/10/20dB selection).
SPAN
Total bandwidth of spectrum display in kHz.
GAIN
Toggles the SDU5500 internal amplifier between high and low gain.
PLOT
Type of trace, Outline or Paint.
MODE
Receive mode (NFM, AM, AUTO etc)
OP.MODE
Type of operation employed, SPECT (spectrum), STRES (step resolution),
CHANL (channel scope).
Section 2-2, 3, 3-1
