ラジオで学ぶ電子回路 - 第2章 AM検波

1 2 AM AM AM AM AM AM AM AM 2-1 1 1000 2 AM -2 AM AM 9kHz AM -1- AM AM AM 1-29 AM A(1+msin st)sin ct sin ct 2-3(a) sin st 2-3(b) 0 2-1 2-4-2- 2-1 (1N60 ) (1S2076A) (1SS97)

2 AM AM 2-5 10mV 10mV -3--4- 2-6 C C R 2-7 AM DC DC V3 DC 0 1-1 R R 2-8 2-9 s B s 2-10 v0/CR m=1 100% B=v0 s=1/CR R fs( s/2 )

3 1 2kHz s=1/CR -5- 100 1 2kHz R 3 2 2-5 1 1-31 2-6 L SL-55GT 2-11 3 F 50mv 1mV C 2-11 5mV 10mV C D 2-11-6- D C 10 50mV 1mV D 1mV 2-11 F C R 5 50 V 100k 500k 0 F 2 2 2 2 R R/2 R/2 R 1-21

4 0 20mV / 13k 25k k 50mV 210k 1/10 5mV 0 SL-55GT D 100mV 100mV 2-4 -7- Q 1/10 1/100 2-12 2 2 2-5 2 2-12 D2 2-11 2-12.

5 D1 C1 i1 C1 D2 D2 i2 D2 D2 -8- 2-13 Ro D1 D1 C1 C1Ro R C 90 CR 2 90 C1Ro 10 C1 C1 R1 R1 Ro C2 C2 2-14 C2 C1 R2 3 5k 10k R1,C1 2-13 R1 100k 5k 10k 2-13 R2 C1 C1 2-7 C1 R2 2-13 2-14 -9-2.

6 R1 R2 R2 3. ( ) C1 4.. 3. 2-14 2-14C2 2-15 C2 v0 C2 v0 Ro v0 R2 C2 v0 0[V] R1 v0R1/(R1+R2)[V] 0[V] R1 v0R1/(R1+R2)[V] 0[V] v0R1/(R1+R2)[V] D1 D1 0[V] 0[V] v0R1/(R1+R2)[V] (b) R2 R1 Ro Ro v0 0[V] v0R1/(R1+R2)

7 [V] Ro Ro-10- -11- 1 M1-1 M1-1 M1-2 M1- 3-12- M1-2 ( ) M1-3 IF -13- 2 SL-55GT D E M2-1 1 1-4 200 1/10 20 1-4 AM 2 200 H AM E E 3 4T 1 -24

8 M2-2 M2-1-14- M2-1 F ST-30 2 ST-30 2 2-12 D 1V 70mV 100mV D E C D -15- RF 9C Yuji Fujihira 2009()