Determining the equalizer – Motorola Broadband House Amplifier BHA-100K/P-R User Manual
Page 19
3-4
Configuration and Installation
2
Remove the equalizer jumper and replace it with the appropriate value equalizer. The
location of the cable equalizer is shown in Figure 3-2.
If system drawings are unavailable, use the following procedures to determine and install the
appropriate equalizer. This procedure assumes normal input signal is present and the amplifier
is operational. Measure the amplifier input signal at the input cable (
IN
) and measure the
amplifier output signal at the amplifier output connector (
OUT
).
Determining the Equalizer
To determine the appropriate equalizer for use in the BHA-100*:
1. Disconnect the input cable from the amplifier
IN
port.
2
Measure and record the signal level of a video channel at the high end of the bandpass,
generally a carrier near 550 MHz.
3
Measure and record the signal level of a video channel at the low end of the bandpass.
4
Reconnect the amplifier input cable.
5
Subtract the measurement of step 2 from the measurement in step 3 to obtain the input tilt.
6
Determine the proper cable equalizer for the BHA-100*.
Table 3-1 helps you choose the correct equalizer and also lists insertion loss at various
frequencies:
Table 3-1
Starline Forward Equalizers – SFE*-*
Frequency (MHz) versus Insertion Loss (dB)
Equalizer
Value
Equalizer
Slope
50 200 300 450 550 650 750 870 1003
SFE-75-
22
16.3 17.3
11.6
9.1 6.0 4.2 2.5 1.0
20
14.8 15.8
10.7
8.4 5.5 3.9 2.4 1.0
18
13.4 14.4
9.7 7.6 5.1 3.6 2.2 1.0
16
11.9 12.9
8.7 6.9 4.6 3.3 2.1 1.0
14
10.4 11.4
7.8 6.1 4.2 3.0 2.0 1.0
12
8.9
9.9 6.8 5.4 3.7 2.7 1.8 1.0
10
7.4
8.4 5.8 4.7 3.3 2.4 1.7 1.0
8
5.9
6.9 4.9 3.9 2.8 2.1 1.6 1.0
6
4.5
5.5 3.9 3.2 2.4 1.9 1.4 1.0
4
3.0
4.0 2.9 2.5 1.9 1.6 1.3 1.0
2
1.5
2.5 2.0 1.7 1.5 1.3 1.1 1.0
SFE-87-
22
16.7 17.7
12.4
10.0
7.1
5.4 3.9 2.5 1.0
20
15.2 16.2
11.4
9.2 6.5
5.0 3.6 2.3 1.0
BHA-100* Broadband House Amplifier Installation Manual