AN 074 Rev E

16 / 24

19-November-2002

Applications Note No. 074

Silicon Discretes

Figure 23. Network Analyzer Screen Shot of Complete Gain-Sloped BGA430 + BGB540 LNB I.F.

Amplifier driving 30 meters / 100 feet of 75 ohm RG-6 Coaxial Cable. The resulting net gain at 950

and 2150 MHz are nearly equal in value, with net gain at 950 MHz = 23.6 dB, and net gain at 2150

MHz = 23.7 dB. The mid band “hump” in gain is approximately 3 dB. Before attaching the 30

meter length of cable to the output of the complete BGA430 + BGB540 I.F. Amplifier, the Amplifier

Gain was 33 dB at 950 MHz and 37 dB at 2150 MHz.

CH1

S 21

log MAG

2 dB/

REF 25 dB

START 900.000 000 MHz

STOP 2 200.000 000 MHz

Cor

Avg

8

Smo

Del

PRm

SCALE

2 dB/div

31 Jul 2002 10:50:23

1

2

3

2_: 26.281 dB

1 450.000 000 MHz

1_: 23.624 dB

950 MHz

3_: 23.653 dB

2.15 GHz

30 m / 100 ft

75 ohm RG6 Coax Cable

BGA430 MMIC

BGB540 MMIC

High Pass Filter

Complete LNB I.F. Amp

B

A

Gain Plot for Figure 23 is taken between points 'A' and 'B'