If all the mechanisms in the car radio are badly worn out and there is no point in restoring them, you can pull out the amplifier from it, which is usually in good working order. After that, it can be used as part of a home stereo system or to amplify a signal from a computer sound card.
Instructions
Step 1
Disconnect the car sound system from the power supply and all connected devices. If it gets very hot, let it cool down. After that, remove the cover from it, remove the mechanism for reading cassettes or discs to get to the board, and then remove the last one. Leave all the removed parts as spare parts for repairing other car radios.
Step 2
Find the amplifier microcircuits - they are bolted to the heat sink, which is often used as the back wall of the radio. Unscrew them, then unsolder. Remove old, dried thermal grease. Under it you will find the types of microcircuits.
Step 3
Find on the Internet or a reference book the so-called datasheet on the microcircuit. This is the name of a document with brief information about a radio component, containing a circuit for its inclusion. Its name comes from the English data sheet - a sheet with data.
Step 4
Desolder from the board all the parts indicated in the connection diagram. Reassemble the amplifier according to this scheme on a breadboard using a microcircuit and soldered parts. Do not pay attention if the values of some capacitors and resistors differ slightly. Observe polarity when installing electrolytic capacitors. Depending on your preference, build a mono amplifier on one chip or a stereo amplifier on two. Some radio tape recorders use dual-channel microcircuits.
Step 5
Apply a thin layer of thermal paste to the flanges of the microcircuits and reinstall the heatsink. If the heat sink is the back wall, install the assembled amplifier back into the radio case. Make sure that the pins of the parts do not touch the housing anywhere.
Step 6
Connect the speakers to the amplifier, then apply power. Use a voltmeter to check that there is no DC component at either the outputs or the inputs. Set the volume control to minimum, then connect the device to a signal source. Then gradually increase the volume to the desired level.
Step 7
Leave the amplifier turned on and supervised for an hour. Make sure that the heatsinks are not heated to a temperature that makes it painful to hold your hand for a long time. If the heating is found to be acceptable, the design can be used.
