Page 82 - Build Your Own Transistor Radios a Hobbyists Guide to High-Performance and Low-Powered Radio Circuits

RF Ant. Filter Three-Stage Amplifier Det
VC &L1 Q1 . Q2, and Q3 03

Loop Antenna

Connect VC1 Osc as Needed
+ 1.5 + 1.5 + 1.5
VC1 Osc Cll C5~
.o1h

L2 R7
1 mH lOOK
C10

ca
T 1~
+ 1.5
Cl
1 U~ R4 Ra
0 1
1N9 14 R9 Audio Signal
R1 100K lOOK 2200
02 56K
1N914

FIGURE 5-2 Block diagram and schematic of a TRF radio using a loop

antenna and RF transformer.
Parts ist
• Cl,C4, CS, C8: 1 lJF, 35 volts

• C2, C6, C9: 0.1 IJF
• C3, C7, Cl0, Cll: 0.01 IJF
• Ri: 56 k

• R2, R5: 6,200

• R3, R6, R8: 2,200

• R4, R7, R9: 100 k

• RI

: 20 k

• Tl: 42IF100 oscillator coil

• L1, L2: 1mH
• L3: 10 mH