At some point my car had some weird voodoo radio install stuff gone on, It had a blaupunkt radio that looked similar to the original radio that should have been in the car, And they had bypassed the fader switch, and had a small external amp of some kind already installed, all of which was not super reliable or functional at all actually...
I decided to upgrade to this much newer VDO/Continental head unit that still retains the styling and look of a classic Euro radio, but has Aux in, Bluetooth, USB, as well as vastly better audio processing options.

Here is a link to this radio, and the tools I used should you decide to upgrade the audio in your W123 or similar car:
➡VDO Continental TR7412UBOR: https://amzn.to/3bXCwun
➡Soldering iron: https://amzn.to/3QqcmPY
➡Solder: https://amzn.to/3c309lp
➡Shrink wrap: https://amzn.to/3C7TZLv
➡Wire snips: https://amzn.to/3JWGeRH
➡Wire stripper: https://amzn.to/3w85Ipi


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