Audio amplifier circuit does not work as expected



Someone that already have armed and made work the audio amplifier
circuit of the book Getting Started in Electronics by Forrest Mims , p.
122.

Already I have made the following revisions:

1) Dual voltage supply checked
2) IC pins 741,386 checked (wrong 386)
3) Value components checked
4) Wiring checked

After this now I hear a strong ¡hummm¡ but not sounds from the
microphone.

Is this what I should hear or what I should hear?
Something missing?
Thanks in advance for any comment

.



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