Hi all! I have a WM-D6C that mechanically functions (play, fast forward, and rewind all work as expected) but has no audio from either the headphone jack or audio out. Additionally there's no feedback on the peak indicator (although the bottom light does light up when set to batt mode). Very similar symptoms to http://stereo2go.com/forums/threads/no-sound-in-or-out-from-a-d6c.2166/ , in fact. After opening it up and not seeing anything obviously broken on the board (such as disconnected wires/solder joints or the like) I brought it to a local repair shop. The technician there was unable to find the audio signal anywhere on the board and suggested that there was a short somewhere but he wasn't able to find it. He also noted that it plays too fast and the speed adjustment doesn't seem to have any impact. The repair technician's recommendation was to sell it for parts and buy a different one, but I'm stubborn and want to get this one working if at all possible. After looking around on this forum for a bit, the first thing I was going to try was to replace the muting module, but because I have a later model of the WM-D6C the muting circuit is built into the main circuit and doesn't use a muting module as stated at https://www.ebay.com/itm/263851487685 Does anybody have recommendations of what I can try to further troubleshoot and/or fix it? I have a multimeter and a soldering iron at my disposal, although I would describe my soldering skills as rudimentary so I would be hesitant but willing to try to work on the smd components. Here are pictures of the boards inside for reference:
Hi and welcome to Stereo2Go. Unfortunately this looks like a classic case of what happens when you use a AC power supply which is wired with the incorrect polarity on the DC output. The output plug should be wired centre negative, which is an unusual configuration used on many Sony products. There are a lot of power supplies sold on Ebay as being suitable for the D6C, which are wired centre positive. They will do this to a D6C. Also, most of the supplies sold on Ebay are switch mode supplies which will destroy the CX20084 chip (IC601) even if they are wired centre negative. If this is the case, your CX20084 will have been damaged (which is why it is running fast), and the DC-DC converter (the rectangular metal can on the main PCB) will have been damaged. There will be no 11V supply, which powers the line amplifier. Therefore, there will be no sound out. It will need the CX20084 replacing and the DC-DC converter repairing using the method which @mihokm has described here: http://stereo2go.com/forums/threads/wm-d6c-dc-dc-converter-fixed.421/ You will also need to replace C607 and C317, which will have been damaged by the reverse polarity connection. Finally, throw the AC power supply in the bin and get a couple of sets of good rechargeable batteries (such as Eneloop Pro) and a charger for them. These will deliver a lower voltage (around 5V) which is safer for the new CX20084.
Hi @Deb64 , Thank you so very much for your help. I just wanted to report back and let you know that you are absolutely correct. Checking the voltage coming out of the DC-DC converter showed 0 volts (when playing); I just finished repairing the DC-DC converter and can now hear sound and see feedback on the peak indicator as expected. I'm now just waiting on the replacement CX20084 to arrive so that I can fix the speed issue. I /think/ that I ordered a genuine one, although I'm aware that there are a lot of knockoffs on the market so we'll see when it gets here :fingers crossed:.
I'm not sure about rechargeable batteries that deliver 5v. When I charge mine, they start at 1,25x4 would give 5v but they are pretty much on their lowest voltage. When charged they show 1,48-1,51v, that would make it on average just shy of 6v.
The Eneloop Pros I have don't go above 5V if I recall correctly. These are great, above 2500mAh each. I have read good reviews of the IKEA LADDA batteries btw if you are not willing to pay a premium for the Panasonic Eneloop brand:
I saw tests of Ladda 2450 on youtube and they were preforming just like Eneloops. They had just tad less miliamps, but there was not significant difference. And there is in price.
I remember seeing a video showing the Eneloop Pro were also sold under a different brand, much cheaper but were practically the same exact battery. It's unfortunate I can't remember the brand name, but will update if I can find it. A quick search on YouTube also reveals there are fake Eneloop Pro sold on ebay, so beware of that. At first glance clearly look similar to the original ones.
That's why I would rather buy Ladda 2450 (there are versions now with lower numbers, I don't know anything about them). Never had Eneloops, but if they are better than Ladda, they aren't THAT better to be worth it.
Can't say anything about that, as I never used Ladda. But even the genuine Eneloop Pro that I have used and use are certainly nothing spectacular in terms of capacity. I mean they're good, but comparable to other brands. I bought them mostly because of longevity rather than capacity. And I also need to mention the D6C does not have that high of a current consumption, unless used on recording mode only. And even on rec, the high current will be on TYPE IV tape, which requires a lot of bias and erase current. The TCD-D7/D8s, for example, are much more power hungry than the D6C (also run on 4 AAs) and even those I consider acceptable in terms of consumption. And I also assume most people who have a decent collection won't use their D6C all day every day.
I didn't use D6C so much to say if they are good enough to power it and for how long. For smaller Walkmans that use 1 battery they last more than enough.
With the Eneloop Pro’s I think I get just over a week’s worth of use in my D6C’s. I use my Walkman for my daily commute to and from work, I use the Walkman about 2 hours a day for 5 days a week. That gives me just over a week’s worth of use. I also swap to a different Walkman at the beginning of each week, so if I use a D6C one week the next will be a DC2, next a different DC2, next a DD9. It goes on like that till I have used all then I start again. 2 x AA Eneloop on the DC2 last a week and a half, DD9 I get about 2 and half days on 1 Eneloop Pro. So based on the same time scale, the DC2 is the most efficient, followed by the DD9 and the D6C is the least efficient of the 3 units.
The DC2 is indeed the most efficient. Per my DD overview table, the DDII, III, 33 and 100 are more efficient; these lack Dolby C and the amorphous head though. The DD9 and DX109 should be roughly the same in terms of energy consumption, both with Dolby C and amorphous head.
