This is a circuit that I've build a few years ago for a friend, who used it in combination with the BLY88 amplifier to obtain 20 W output power. From the notes that I made at the original schematic, it worked fine with a SWR of 1 : 1.05 (quite normal at my place with my antenna).
Part | Total Qty. | Description | Substitutions |
R1,R4,R14,R15 | 4 | 10K 1/4W Resistor | |
R2,R3 | 2 | 22K 1/4W Resistor | |
R5,R13 | 2 | 3.9K 1/4W Resistor | |
R6,R11 | 2 | 680 Ohm 1/4W Resistor | |
R7 | 1 | 150 Ohm 1/4W Resistor | |
R8,R12 | 2 | 100 Ohm 1/4W Resistor | |
R9 | 1 | 68 Ohm 1/4W Resistor | |
R10 | 1 | 6.8K 1/4W Resistor | |
C1 | 1 | 4.7pF Ceramic Disc Capacitor | |
C2,C3,C4,C5,C7,C11,C12 | 7 | 100nF Ceramic Disc Capacitor | |
C6,C9,C10 | 3 | 10nF Ceramic Disc Capacitor | |
C8,C14 | 2 | 60pF Trimmer Capacitor | |
C13 | 1 | 82pF Ceramic Disc Capacitor | |
C15 | 1 | 27pF Ceramic Disc Capacitor | |
C16 | 1 | 22pF Ceramic Disc Capacitor | |
C17 | 1 | 10uF 25V Electrolytic Capacitor | |
C18 | 1 | 33pF Ceramic Disc Capacitor | |
C19 | 1 | 18pF Ceramic Disc Capacitor | |
C20 | 1 | 12pF Ceramic Disc Capacitor | |
C21,C22,C23,C24 | 4 | 40pF Trimmer Capacitor | |
C25 | 1 | 5pF Ceramic Disc Capacitor | |
L1 | 1 | 5 WDG, Dia 6 mm, 1 mm CuAg, Space 1 mm | |
L2,L3,L5,L7,L9 | 5 | 6-hole Ferroxcube Wide band HF Choke (5 WDG) | |
L4,L6,L8 | 3 | 1.5 WDG, Dia 6 mm, 1 mm CuAg, Space 1 mm | |
L10 | 1 | 8 WDG, Dia 5 mm, 1 mm CuAg, Space 1 mm | |
D1 | 1 | BB405 | BB102 or equal (most varicaps with C = 2-20 pF [approx.] will do) |
Q1 | 1 | 2N3866 | |
Q2,Q4 | 2 | 2N2219A | |
Q3 | 1 | BF115 | |
Q5 | 1 | 2N3553 | |
U1 | 1 | 7810 Regulator | |
MIC | 1 | Electret Microphone | |
MISC | 1 | PC Board, Wire For Antenna, Heatsinks |