Convert a car stereo to a workbench radio
I
bought this thing at flea market for four euros. I thought to use it as
a basis for some amplifier project. No luck this time, the power amp IC
was rated at 2 x 5 watts into 4 ohms only. I decided to convert it to a
standalone radio instead. My little workshop is at the basement, mostly
under ground level and radio reception is very poor. I have tried
several radios there with no luck. But, car radios must have been
designed to cope with challenging receiving conditions (?).
I would need a telescopic antenna, a speaker, a power supply and a
connector for it. Luckily I was able to find all items in my junkbox.
It was easy to remove the cassette player. I spent some time finding
out how the system mutes the radio when cassette player is in use. Two
wires had to be soldered together, all other wires to the cassette unit
could be removed.
The antenna has to be insulated from the chassis. I removed the
original antenna connector and used two wooden pieces to make a crude
but working base for the antenna. A short wire connects the antenna
mounting screw to the circuit board.
I installed a standard dc connector for the power supply. It fitted
nicely after some filing and stays in place without any clue. I use a
14 V AC adapter
(wall wart) which is perfect for this (and probably useless for anything else). I wonder where that came from?
Without the cassette player there was plenty of room for a small speaker. I mounted it to the top plate with four small bolts.
Time
well spent! My new workbench radio works really well. Placed in
vertical position it doesn´t take much space on the shelf. I didn´t
bother to make it look pretty although it wouldn´t be difficult to make
a simple box from plywood or something.
©Jukka Korppi 2015
