At 01:28 PM 5/31/2012, Steven Johnson wrote:
>would help to have a schematic.   I think I have the Heidelberg IV but
>anything around that model will probably
>be close enough.

Steve, start pulling numbers off the radio itself and search the
net.  Some VW radios may have been made by Blaupunct; some definitely
were Japanese (brand starting with F, written in an italic font, I
vaguely (mis?)remember).

This may be a good source once you've got it narrowed down:
http://elektrotanya.com/?q=Audios&page=10 - it comes up on the B page
because Blaupunct (sounds fancy in German, doesn't it.  Whee, I've
got a Blue Dot radio!) did make one radio they called Heidelberg.

Yours,
David
ps - I presume you've been inside a car stereo before?  If not you
may be in for a bit of a surprise.  Service access wasn't high on the
priority list of the ones I've had open.