2003 Sep 19 10
Philips Semiconductors Product Specification
VHF push-pull power MOS transistor BLF278
Notes
1. American Technical Ceramics capacitor, type 100B or capacitor of same quality.
2. L1 to L10, L13, L14, L17 to L21 and L23 are striplines on a double copper-clad printed-circuit board, with fibre-glass
PTFE dielectric (ε
r
= 2.2), thickness
1
⁄
16
inch; thickness of copper sheet 2 × 35 µm.
3. L22 is soldered on to stripline L21.
L17, L18 stripline; note 2 43 Ω length 24.5 mm
width 6 mm
L19, L20 stripline; note 2 43 Ω length 66 mm
width 6 mm
L21, L23 stripline; note 2 50 Ω length 160 mm
width 4.8 mm
L22 semi-rigid cable; note 3 50 Ω ext. dia. 3.6 mm
outer conductor
length 160 mm
R1 metal film resistor 10 Ω, 0.4 W
R2, R7 10 turn potentiometer 50 kΩ
R3, R6 metal film resistor 3 × 12.1 Ω in
parallel, 0.4 W
R4, R5 metal film resistor 10 Ω; 0.4 W
R8, R9 metal film resistor 10 Ω±5%, 1 W
R10 metal film resistor 4 × 10 Ω in
parallel, 1 W
R11 metal film resistor 5.11 kΩ, 1W
IC1 voltage regulator 78L05
T1 1:1 Balun; 7 turns type 4C6 50 Ω
coaxial cable wound around toroid
14 × 9 × 5 mm 4322 020 90770
COMPONENT DESCRIPTION VALUE DIMENSIONS CATALOGUE NO.
