This post concerns the original 424, the white or grey or beige coloured one, also referred to as the Mark one, MK I, M1, original gangster. I ahve manuals for the other versions of the 424 in other blog posts.
Here is the .pdf file forthe Tascam 424 Service manual with schematics free download, approximately 10 megabytes
And Here is the User’s manual
At the time of writign I ahve filmed a tear down of this model. Any more videos I film featuring the model will be added to the playlist below;-
Tetrakan Supermonobloc 
Hello sir
I can’t find the service manual for the 464, it’s my first time here so I’ll look around your blog,
Thank you sir
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Thank you for posting this! Do you know if it’s possible to take apart the power supply for this one? Mine is not putting out enough Volts, want to see if I can fix it. But It’s a tank!
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I don’t actually have the the original PSU for my 424, but I imagine its a transformer based design? In which case I would guess that if you replace fuingible parts like any electrolytic capacitors then the PSU will work again. However its very easy and relatively inexpensive to buy a replacement – any 12 volt center negative wall wart will do.
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Yes, I concur. Thanks for such a nicely scanned manual that we can actually read unlike some from a Hi Fi Place. You have made a lot of people happy with just this one manual but don’t stop here as I bets you can do more. I am a past Teac Employee and this manual is as good as they get.
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Thanks Sam. I also wanted to say thank you for all the contributions you’ve made to forums like tapeheads, homerecording etc, your input has been particularly helpful to me as I was trying to figure out how to repair these things, and I know the knowledge you have shared there has been helpful to other people I have spoken to who are trying to keep these cassette recorders working.
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Thanks for your kind words. It becomes harder to get the job done now that fewer people are doing the work.
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