7-99

Figure 24. Equivalent Circuit for RXRF Input.

Figure 26. Equivalent Circuit for the RXIF Output and Recommended Matching

Circuit for 110.592 MHz IF.

Figure 25. Equivalent Circuit for TXIF Input.

PCB GND

TXRX VCC

EXTERNAL COMPONENTS

ARE FOR TYPICAL i/p SWR

OF 1.3:1 OVER 1.85

TO 2.55 GHz

15

TXRX GND

11

7

8

10

2.7 pF

LNAREF

3.3 pF

RXRF

50

Ω i/p

BIAS

BIAS

TO MIXER

LNA STAGE

TXRX GND

TXRX VCC

USE d.c. BLOCKING Cs TO

AVOID CHANGING d.c. BIAS

CONDITIONS. 22 pF MAX. FOR

QUICK TURN ON.

TXIFB 6

TXIF 5

10

TXIF IN

11/15

TX i/p STAGE

10 k

10 k

RECOMMENDED DRIVE

LEVEL IS 300 mV pk-pk.

VCC

EXTERNAL COMPONENTS

SHOWN ARE FOR 110.592 MHz

I.F. AND TYPICAL 50

Ω o/p

SWR OF 1.3:1

TXRX GND

750

RF

50

Ω o/p

11/15

4 RXIF

LO

3 RXIFB

8.2 pF

6.8 pF

120 nH