Almost 2 years ago I got a D6C in perfect cosmetic condition as a free addition to a purchase of two cassette decks. It was listed as broken having the classic speed problem. I thought perfect, I can fix this. As simple as putting an order on Ebay from China and some surface mount soldering. I ordered replacement and discovered I got a package of 5 chips after a few weeks. Unfortunately I did not have time to do the fix for a long time. Once I did the replacement I discovered that the chip was getting very hot and I realised what I already suspected, the chips were fake but I could not be 100% sure as there might been other faults with the D6C. I did check as much as I could like the DC-DC converter and everything looked ok but I could not measure voltages etc as I didn't want to run it while the chip was getting hot and risk causing more faults. I put the project on hold, I actually both another D6C in working condition but cosmetically not as good meanwhile. Sometimes later I was in contact with a seller in Japan that seemed legit so I ordered one chip from him. Again a long time between receiving the chip until trying it, same result, chip got hot. At this point I was ready to give up, no way I was going to order any more chips not even 100% convinced the problem was not caused by other faults in the Walkman. By accident I found a broken WM-DD11 on Ebay, it was in a very sorry state but low price. I think the seller was surprised about my interest . The walkman was very corroded including half of the PCB but the chip area looked fine. The transplant went fine although a couple of the pad were coming loose after too much soldering. Success! The Walkman was working fine and after maintenance and changing rubber and counter belt it runs perfect. This was at less than half the cost of buying a single fake chip. Moral of the story, don't buy these chips through Ebay, or if you do make sure to verify them before the return period is over. Better in both price and success rate, look for old broken Walkmans that have this chip instead.
Good on you for solving the problem finally. I was lucky enough to get 5 chips from china that turned out to be fine but that was around five years ago, I hear people are really having trouble getting hold of them nowadays which is unfortunate. In theory a daughtercard replacement for the chip could be made using something like the Arduino or Pikaxe platform, but one would have to have the time and equipment to be able to reverse engineer it. Its such a great feeling to being something back to life that everyone else who had it before gave up on. I have one with a broken record pot and have not been able to find a replacement original, I think that one might get used as a parts unit for the other ones... Be sure to bias the WM for the tapes of your choice, the results will blow you away. The best tutorial for this is here: http://stereo2go.com/forums/threads/sony-wm-d6-d6c-calibration-tutorial.7164/
I know this is a year-old thread, but does anyone know if this chip might be found in aWM-F5? I understand that it shares much of the DD architecture.
Thanks, I was hoping it might have it as I have an otherwise nice D6C with a chipmunk problem, and a corroded F5.
Check the DD genealogy thread in my footer for more details, including the F5 as it is a WM-DD with radio after all!