CA240 is a car amplifier product by HARMAN KARDON 80s era. It can be reaching 40 Watt Audio Output at 8 Ohm Load and until 100 Watts Out at 4 Ohm Bridge Output.
INFO
The Car Power Amplifier need 14,4VDC to produce 40 to 100 Watts output.
SCHEMATIC DIAGRAM
Download the manual here: ( DOWNLOAD )
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The preamp circuit on this amplifier uses transistor number 2SC2240, there is a transistor mute feature by Q406 and Q408.
Furthermore, the voltage amplifier stages uses a 3-stage transistor system, ranging from Q410 to Q424 and Q412 to Q420.
Transistor servo driver uses only 1 transistor, namely Q418.
For Driver Amplifier Q422 and Q426 using transistor numbers C2591 and A1111.
Final Power transistors use 2 pairs of transistors numbered 2SC3181 and 2SA1264.
NOTE
There are 2 kinds of voltage on the amplifier, namely symmetrical 24VDC and symmetrical 31VDC.
24VDC voltage is required by the driver especially the Final Power Amplifier but requires a large current.
The preamp and voltage amplifier stages require a higher supply voltage but its require much less current.
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