Hello folks! Hope all is well with everyone here!! I posted this on the TapeHeads forum as well so I hope it's alright to ask here as well. I spent all day going over everything I could think of and I gotta say that working on these units isn't horrible but there is quite a bit of complexity to them so I'm thinking it's something simple I am overlooking possibly as the unit works so well on AC without a single flaw. Any help at all is very much appreciated here!! I got a D6 at auction quite cheap as an non working unit but apparently they didn't see that the pause button was held down. So that was a bonus as on AC power it works and sounds great. However when I tried battery power I ran into a problem. The unit acts as if it has no power at all when on battery. No battery light, no movement, no sound. So upon looking further I have verified that I am receiving power through the unit across the whole PCB. You can go off of either battery post soldered on the PCB and you will get 5.35V (I am using rechargeable batteries) across most of the solder joints all across the board so I know that the batteries are making a good connection to the board. Then I tested continuity on the S901 switch and it is also making a good connection and working as it should. I also tested the DC-DC converter and it is working and making a good connection as well. So then I am at my final problem as of which I am baffled by. The stop/eject button works flawlessly on AC power or no power but as soon as batteries are installed and only with batteries, the stop/eject button starts hanging up as if button was way to tight or getting hung up. Remove the battery pack and the stop button works all smooth again. Never have I seen a mechanical button act up due to an electrical connection. Here is a link to a couple videos of my explaining the situation. Hopefully you all are able to view them. https://photos.app.goo.gl/fwbjxhxwfpVN6erG6 Any advice, help, criticism, anything at all is welcomed here as I am trying to think of what's the next best approach to figuring this out. Thank you everyone so very much!! Kind regards! Lincoln
may be a long shot, but there is a switch inside the dc jack that switches between the battery power and the dc input, depending on what is connected, so for example, the recorder will not work if you have a dc jack plugged in the machine but not plugged in to the wall, with or without the battery. This switch is supposed to to close when the jack is extracted, maybe the contacts inside are dirty.
Seriously man you are a life saver!!! I had thought of that before but thought that the board wouldn't receive any power if the switch was activated like you say. So I got some contact cleaner and worked the jack in an out like 20 times. There was so much grit, dirt, and who knows what else stuck in the jack/switch and now I can report back that that was a successful fix and I am so very thankful for the tip sir!!! THANK YOU
Hello Lincoln Scott , I have seen and have had that same issue with products in the past I have even had to replace a defective jack too . Sincerely Richard
Ah the magic that comes in a deox spray can. Similar to the audio problem on DD Walkman where only one channel is present but with the headphone plug partially removed both channels are working. Can be fixed by use of deox spray on a scratchy volume pot that has not been moved in years. Remove the case, spray the pot inside with a fine tube nozzle and then leave overnight after several full range rotations of the volume wheel.
Well I was super happy there for a bit.. Got it all working and right and then successfully fried it all in one day. It starting acting up so I went to clean the jack again and noticed that the prong inside the jack wasn't protruding enough into the jack (the one that presses on the outside of the barrel) so I like an absolute IDIOT stuck a dental pick in there to bend it back some WHILE THE DAMN BATTERIES WERE IN and shorted the two contacts resulting in frying one of the NPN or mosfet transistors on the CP602 resulting in the motor running continuously when power was applied. Can't tell you how stupid I feel... So no I've tasked myself to fix this one myself no matter what even if it results in me turning this thing into a pile of parts. And I know some will say maybe it was bad before all this but I had left the player on AC with batteries installed for over 3 days while playing for a full day (12+ hours) without any constant running. I was confident this one was good and working and I just had to fry it..
Well, it’s a pity but it’s not the end of the world. It should be fixable. You need some good equipment to remove cp602 without lifting pads. So only attempt it if you have a bit of experience, good luck
Oh dear. The CP602 issue with a D6. Well it may have failed anyway. Similar thing happened to my D6. Suddenly started running at double speed and creeping forward even when in STOP mode and batteries were not removed. Fixing it involves removing the CP602 main IC and replacing any fried components inside that IC. A bit tricky but if you're not wanting to attempt that I'd suggest chatting with @Deb64 on this forum. She sometimes takes on repairs of this nature. The main problem these days is you cannot find a replacement IC for the speed control module on a D6. That constant running is a sign it's cooked. Usually happens when the wrong polarity AC adapter is connected but I'd say shorting that input plug would have the same consequences. It looks a nice example from your photos and worth rebuilding it for sure.
Hello Lincoln Scott, your not the fiorst one to do a mistake like that and I agree 100% with Silverera " The main problem these days is you cannot find a replacement IC for the speed control module" that will be a tough one you might have to buy a broken parts unit . I wish this was the glory days back in the 1980s and 90s and even early 2000s there were tons of Sony factory stock and tons of Electronic parts houses Like Andrew Electronics . Sincerely Richard
Just to touch back and give an update! I was able to successfully remove the CP602 daughter board that held the bad NPN or FET. De-potting was done with some acetone and to my surprise I was able to remove them both and successfully replace them! This was a first for me as I had also never soldered anything this small. Was a good challenge as well as a learning experience but gave me good feeling of accomplishment when it turned on and played as it should!! So lesson learned!! DONT PUT ANYTHING METAL IN THE DC JACK WHILE IT IS UNDER POWER!! Haha! Deb64's guide was a life saver here! It's nice to know that I can at least repair one if I come across another or have to fix mine! My D6 has been playing wonderfully ever since. Haven't messed with the other daughter boards that fail commonly (Muting module & EQ) so hopefully the keep going too! Thanks again for all the help everyone!
