User`s manual

100-M0056X2B 26 of 28

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Figure 11 - BDC Connectors

Table 5 - DB-9 Connector Pin Out for the D/C

Pin Signal Notes

+12Vdc

Power supply must be able to source at least

500mA. Voltage should not drop below +10Vdc.

GND

Power ground

2, 4-9

Not Connected

10.0 Cable Losses

10.1 Coax Cable

Cable losses must be taken into consideration if the D/C is located a great distance from the

receiver. As mentioned above long cable runs can contribute to more resistance in the lines and also

can contribute to signal attenuation because of the additional capacitance. Even when using a good

coax cable such as RG59/U the attenuation of the signal can be significant. For example, RG59/U

coax will drop approximately 2 dB per 100 feet at 50 MHz and 8 dB per 100 feet at 900 MHz. The

intermediate frequency (IF) in this system can fall between 49 MHz to 850 MHz. Cable losses in this

range for an RG59/U are shown below in table 5. An inline amplifier matching the cable losses should

be considered if losses exceed 6 dB.

9 connector for local

power

BNC c

onnector

–

IF frequency

output

RF Input

Power Switch

for local