Elenco Electronics AM-550TK Instruction Manual download pdf (Page 15)

-14-

Oscilloscope

Generator

Probe

Output Adjust

10μF

Figure 8

GND

R15

GND

R15

Connect the oscilloscope and generator to your circuit

as shown in Figure 8.

Set the generator for a frequency of 1kHz and minimum

voltage output. Set the oscilloscope to read .5 volts per

division. Turn the power ON and slowly increase the

generator output until the oscilloscope displays 2 volts

peak to peak (Vpp) at TP8. Move the oscilloscope

probe to TP6 and record the input voltage here:

Vin=___________ Vpp

(at this point you may want to verify the AC Gain).

Move the oscilloscope probe back to TP8 and slowly

increase the frequency from the generator until the

waveform on the oscilloscope drops to .7 of its original

reading, 1.4 Vpp or 2.8 divisions. Use the oscilloscope

probe to check TP6 to make sure the input voltage did

not change. The frequency of the generator when the

output drops to .7 of its original value is called the high

frequency 3 decibel (dB) corner.

Repeat this procedure by lowering the frequency from

the generator to obtain the low frequency 3dB corner.

Leave the oscilloscope connected to TP8 and turn the

power OFF. By subtracting the frequency of the low

corner from the frequency of the high corner, you

calculate the bandwidth of the Audio Amplifier. Your

bandwidth should be greater than 100kHz.

AC BANDWIDTH

1 2 ... 10 11 12 13 14 15 16 17 18 19 20 ... 31 32

No comments

Elenco Electronics AM-550TK Instruction Manual Page 15