fmod = 1.0 kHz, fdev = 3.0 kHz. MC3371 at fRF = 10.7 MHz (see Figure 11).
The base of the Colpitts oscillator. Use
probe or a 鈥渟niffer鈥?to view the wave鈥?/div>
form without altering the frequency.
Typical level is 450 mVpp.
VCC
Waveform
1
OSC1
2
OSC2
2
OSC2
15 k
The emitter of the Colpitts oscillator.
Typical signal level is 200 mVpp. Note
that the signal is somewhat distorted
compared to that on Pin 1.
200
碌A
3
MXOut
VCC
4
3
MixerOut
Output of the Mixer. Riding on the
455 kHz is the RF carrier component.
The typical level is approximately
60 mVpp.
1.5 k
4
VCC
100
碌A
Supply Voltage 鈥?.0 to 9.0 Vdc is the
operating range. VCC is decoupled to
ground.
5
IFIn
5
IFIn
6
DEC1
7
51 k
60
碌A
1.8 k
53 k
Input to the IF amplifier after passing
through the 455 kHz ceramic filter. The
signal is attenuated by the filter. The
typical level is approximately
50 mVpp.
6
7
DEC1
DEC2
DEC2
IF Decoupling. External 0.1
碌F
capacitors connected to VCC.
8
Quad
Coil
8
Quad Coil
VCC
Quadrature Tuning Coil. Composite
(not yet demodulated) 455 kHz IF
signal is present. The typical level is
500 mVpp.
10
50
碌A
6
MOTOROLA ANALOG IC DEVICE DATA