Hello, I recently was lucky to get my hands on two WM-D6C in perfect conditions. I really love listening to these ones, but it also costs me damn loads of batteries, so I guess it's time to get a proper power adaptor (European). Preferable an original if anyone got one laying around and willing to sell it? Cheers
Original ones are like gold dust and cost a fortune! I got a generic one here - https://onlinesparesdirect.com/catalogsearch/result/?q=WM+D6C. It works fine but be mega careful of generic ones as sometimes they say they are D6C compatible but have the wrong polarity. You REALLY dont wanna be using the wrong polarity. Its a very expensive mistake to make!
Yes, read a lot here in the forum about the danger of using a generic one, that's why I preferred the original. Anyway, will order one from the site you recommended and hope that an original will be up for sale Thanks
DON'T USE A PLUG IN POWER SUPPLY on a WM-D6C! Recently one of my customers managed to destroy a CX20084 ic on his D6C while running it on batteries. Also, he had 3 Sony supplies, all rated at 6V and with the correct polarity, which he tested with a Fluke meter. They delivered from 6.5 Volts (the lowest) to 7.6V (the highest). Shortly after that, I had a repair enquiry from another customer with a faulty CX20084, which he insists has only ever been run on batteries. I tested a fresh set of alkaline batteries (Procell) and a set of 4 were delivering 6.3V. Although I have never seen a datasheet for the CX20084 (and I'm not likely to see one either), I think Sony were running these chips at the extreme upper limit of their supply voltage at 6V. Anything over 6V is taking a risk. The CX20084 is connected directly to the incoming power supply, which is not switched. Therefore, if you plug in supply with the wrong voltage or incorrect polarity, you will destroy the CX20084 instantly, even if you don't switch the walkman on in any way. Add to this the fact that replacement CX20084s are now becoming extremely difficult to obtain, I recommend that you only run your D6Cs using rechargeable AA batteries (such as Eneloop Pro). These deliver a lower voltage than alkaline batteries (normally 1.25V each) so a set of 4 will deliver 5 volts, which will run your D6C very well.
@Deb64 Thanks, That advice feels more safe, I will get some Eneloop Pro straight away. What about the original power adaptor? Do you still recommend using Eneloop Pro over the original power adaptor? Thanks for the advice, did not even think about rechargeable batteries.
I think Eneloop Pros are the better option as you will be running the CX20084 at 5V rather than 6V (or more). It will be a lot safer. One reason why I believe that the CX20084 should not be run at 6V is that Sony re-designed the main circuit board on the D6C in 2001. They replaced the CX20084 with the CX069A, which is the chip used in the TC-D5 recorders. The re-designed motor drive circuit is similar to that used in the D6, apart from a different chip. Why would a manufacturer go to the expense and trouble of re-designing a product which is so close to the end of its production life? A high failure rate in production test and during the warranty period would be a good reason to do so.
@Deb64 do you think it makes better sense to run these things off a 5V wall power supply? Think I saw a thread a ways back where someone talked about feeding the D6C lower and lower voltages with a variable PSU, and it was fine with a surprising range. I've got a harebrained scheme where I start a youtube channel for rare tape rips played through a D6C. If I use my Eneloops I'll have to complicate the shot with my hands hitting play, but if I use the DC jack I can plug it into the wall off-camera with the play button already depressed.
The problem with using a 5V wall supply is that most of those sold these days are switch mode type supplies. These usually have AC coupling from the primary to the secondary side in the form a Class Y capacitor, which is put in the circuit to supress RF interference. This results in a common mode AC signal on the output which is high voltage but low current. In the UK, where we have 230V AC mains, the peak to peak voltage of this common mode signal can reach nearly 300V relative to mains earth. So far, I have repaired 2 D6Cs where the CX20084 was destroyed by the use of a switch mode power supply. I have attached a photo showing the oscilloscope traces of the two sides of the connector. When measured with a multimeter, they showed a nice steady 6V DC but it is the common mode signal which will destroy the chip.
That's interesting and bone-chilling in equal parts. Looking up the difference between linear and switching power supplies, I guess that's why all my vintage ones are so much heavier. I'll absolutely refrain from plugging my D6C into the wall unless I'm sure that I'm not using a switching PSU. Thanks for the heads-up. If I were to get my hands on a 5V linear power supply with the right polarity, would that be as safe as four AA batteries?
Generally the linear supplies are much bigger and heavier. That said, I normally open them up and take a look at the circuitry inside to make absolutely sure it is a linear supply. If you get a 5V linear supply, check the output voltage before plugging it into your D6C. It may be higher than 5V. I mentioned earlier in this thread that a customer had tested some genuine Sony 6V supplies and found them all to be over 6V. The 300mA supply, which he states is recommended for use with the WM-D6C, gives an output of 7.6V, which is far to high to use on a CX20084. The linear supply will never be as safe as using batteries because it is possible for the regulator to fail (although such a failure would be very unusual) but, as far as I'm aware, it's not possible for a set of batteries to start giving out a higher voltage (bearing in mind that I have meaured 6.3V from a set of 4 fresh alkaline batteries).
I try to voltmeter check all my power supplies (I'm a thriftstore rat and dumpsterer, used to gear that only nearly works) but with my walkmans I'll be double careful. I really appreciate the warning.
Thanks for all the good information, Deb64 ! I always used my D6C with NiMH cells exactly because of the fear of destroying the CX20084 chip. The original power supplies like AC-9W are all unregulated, so they will give a higher voltage with no load. The voltage will drop when loaded, but the initial spike is likely enough to kill the chip. Maybe not the first time, but in time it will. I have checked many 6V power supplies from different brands and most of them are unregulated. The only exception was the SONY TCD-D8 power supply, but given it has 100-240V input rating, it is a switching supply for sure. So it is also my recommendation to use this unit on recharghable batteries only.
I ended up getting a BRZHIFI brand 5v power supply off eBay to run my D6C while it's sitting on my desk. Linear, regulated, nowhere near 6v, built like a truck, and it's got USB ports to power my DAC at the same time. I just had to splice the wires in the output cord to make it center negative. So far it's working great.
What is the size of the DC power connector for a Sony WM-D6C? Anybody got a part # for a suitable connector?
