August 1986

9

Philips Semiconductors

Product specification

UHF linear power transistor

BLW32

Fig.10 Bias circuit for class-A amplifier at

+Vs

+VCC

+VBB

0

R9

R8

R7

TR1

C3

R5

R4

C2

C1

R3

R2

D1

R1

D2

C4

R6

MGP437

List of components:

C1 = 100 pF ceramic capacitor

C2 = C3 = 100 nF polyester capacitor

C4 = 10

µF/25 V solid aluminium

electrolytic capacitor

R1 = 150

Ω carbon resistor (0,25 W)

R2 = 100

Ω preset potentiometer (0,1 W)

R3 = 82

Ω carbon resistor (0,25 W)

R4 = R5 = 2,2 k

Ω carbon resistor (0,25 W)

R6 = 12

Ω carbon resistor (0,5 W)

R7 = R8 = 820

Ω carbon resistor (0,25 W)

R9 = 33

Ω carbon resistor (0,25 W)

D1

= BZY88-C3V3

D2

= BY206

TR1

= BD136

Information for wideband application from 470 to 860 MHz available on request.

1. Three-tone test method (vision carrier

−8 dB, sound carrier −7 dB, sideband signal −16 dB), zero dB corresponds to

peak sync level.

Intermodulation distortion of input signal

≤−75 dB.

2. Two-tone test method (vision carrier 0 dB, sound carrier

−7 dB), zero dB corresponds to peak sync level.

0 dB to

−20 dB.

handbook, full pagewidth

2

−50

−65

0

0.5

1

MGP438

−55

−60

30

0

20

10

1.5

Po sync (W)

dim

dcm

dim

(dB)

dcm

(%)