ADC Dual Inline Tower Mounted Amplifier System 16

ADCP-75-214 • Issue 2 • September 2006

2.4Bias-T Installation

2.4.1Mechanical Attachment and Cable Connections

Caution: Prior to installing any Bias-T unit, ensure that the BTS transmitter output is turned off and that precautions are taken to ensure that the transmitter cannot be activated during the equipment installation.

The Bias-T is installed either inline with the antenna feeder cable or directly to the BTS antenna port. Integrated lightning protection is built into each Bias-T unit. There is no additional mounting hardware required. Bias-T can be installed in either of the two antenna feeder cables for each MHU. Connect the Bias-T as follows:

1.Connect the Bias-T “BTS” connector inline with the antenna feeder cable or directly in the BTS antenna port.

Note: Orientation of the Bias-T is critical, BTS end should face the BTS and ANT should face the antenna.

2.Connect the coaxial run going to the MHU to the “ANT” port of the Bias-T.

3.Connect the mini coax cable to the TNC connector of the Bias-T unit.

4.Connect the other end of the mini coax cable to the PDU front panel SMB connector MHU1…3 (whichever is being used).

5.Connect the ground cable to the Bias-T ground terminal (see Figure 9).

6.Connect the other end of the ground cable to the site-grounding pole.

	BTS	ANT
		Bias-T kit
		Freq: 800 - 2200MHz
	ASSEMBLED IN	Temp: -40 to +65 C
	ASSEMBLED IN	Input: 5 to 24VDC
	KOREA	Input: 5 to 24VDC
	KOREA	Max Current: 2A
		Max Current: 2A
	Date: YYYY/MM/DD	P/N: 1344027
		S/N: XXXXXXXXX
	DC	GROUND TERMINAL

21298-A

Figure 9. Bias-T Ground Cable Connection

2.4.2Additional Lightning Protection

ADC recommends that the operator install further lightning protection between the MHU and Bias-T. It must allow the DC voltage to pass through the lightning protector, if it does not then the Bias-T should be mounted on the antenna side of the protection.

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