Audio Engineering

Preamplifi ers and Input Signals 187

2K2

10 K

10 K

0.1μ 10 K 0.1μ

0.01μF

0.01μF

0.1μ 0.1μ

0V 0V

0V

0V

0V 0V 10 V

IN4148

IN4148

IN4148

IN4148

IF input IF output

1K5

1K5

10 K

2K2

Figure 7.15 : Typical diode switching circuit, as used in RF applications.



Inputs  Output

0.47μF

0.47μF

0.47μF

0.47μF

100 K

0V

100 K

0V

100 K

0V

0V

0V

100 K

0V

SW 1

1M0

Figure 7.16 : Use of DC blocking capacitors to minimize input switching noises.