Pre-Amp Mic Condenser
Microphone amplifier circuit is simple, consisting of 2 levels. with wide dynamic regions, small noise, and can with a long cable about 50 meters.
all capacitor (elco) using 25-volt
to avoid the buzzing sound, use a good regulator supplay
This circuit can provide voltage 6-20volt
This circuit uses low noise transistors are type types: BC 650 C but the transistor is hard to find, so you can replace it with 109 BC is no less good. This condenser mic element in it is a very sensitive microphone, and to use this mic condenser required voltage between 2-10 volts, for that we can resistors in series with 1K-10 K ohms, in the picture above the tide 1k ohms
Pin BC109
- Emitter
- Base
- ollector, connected to the case
BC109 limiting values
collector-base voltage 30 V
collector-emitter voltage 20 V
emitter-base voltage 5 V
collector current (DC) 100 mA
peak collector current 200 mA
peak base current 200 mA
total power dissipation Tamb £ 25 °C - 300 mW
storage temperature 65 +150 °C
junction temperature 175 °C
operating ambient temperature -65 +150 °C
DC current gain (hFE) IC = 10 mA; VCE = 5 V 100 -- 270
