kgallen Posted March 20, 2022 Report Share Posted March 20, 2022 @BearBoy and I recently expanded our aged horizons and toyed with Amazon Japan and bought some new (new) MD blanks. Buoyed by that experience I recently decided to go another step and risk my hard earned cash with Ali Express. I do quite a lot of ‘hobby electronics’ but it’s not an online vendor I’ve ever been tempted to try. Expectations were not high. A few weeks back I bought a Sony MXD-D4 (yes guys another one…) from eBay. But this one was listed with MD issues. I can sort that, I thought. Well yet again I bought a thoroughly minging machine. The thing stinks. I think it’s been on 40 a day for the last 20 years. I lifted the lid first and I’m glad I did. The MD overwrite head was folded up like a concertina. No wonder it had C13 reported. Replaced the CD eject belt. CD section works fine now. Took out the MD drive and removed the OWH assembly (pretty straightforward). New load/eject belt as a standard service procedure. MD drive back in the machine and it plays. Result. Steal an OWH from another drive that has issues but OWH is known good. Fit to the D4 drive. Nope still won’t record. Regardless, stripped the whole machine down and gave it a severe dose of isopropyl alcohol and washing up liquid. Damn thing still stinks. Break out the LPM and the Iop jig. Short story is this is the first machine I’ve come across where the laser is genuinely aged. The read laser power can be calibrated ok - hence the machine can indeed play. However the laser power can’t be adjusted for the write power. Even at a crazy 150mA of Iop (bearing in mind the factory cal for the laser is around 56mA), I can’t get more than about 6mW of write power out of it. Thoughts of doing my first laser replacement… Start looking around for a KMS262A laser assembly. Find one on Ali Express and it’s about £55 delivered to the UK, so not cheap and not guaranteed to fix the machine. Browse a bit more. It’s fairly clear some of these sellers have no idea what the stuff is they are selling. Come across some pictures of an MDM-7 drive. Find some additional pictures of the underside showing the BD board with an EMC shield and a fitted 90MHz crystal. So the MXD-D4 can do 4x dubs from its internal CD drive. This means the MD drive is a variant of the MDM-7A drive we find in x40 decks. The drive is an MDM-7X2A and you can spot it as it has this EMC shield and the 90MHz crystal which is not found on the usual ‘single speed’ drives. If you like, this MD drive is like a 4x CD-ROM drive except it’s MD. So back to Ali Express, these pictures are ticking all of the boxes. But is it BS? The seller talks about a laser. The seller talks about CD and BMW cars. If I order one, what the heck am I going to get. Will it look anything like the pictures? Get a rush of blood to the head and shell out £84. In the name of research. There is no way this exercise will cost in… To be continued… Quote Link to comment Share on other sites More sharing options...
BearBoy Posted March 20, 2022 Report Share Posted March 20, 2022 A brave new frontier! I've never used Ali Express personally but know people who have without any issues. I suspect that, like eBay, it depends on the seller but you should be protected if everything goes pear-shaped. Any idea when it's likely to arrive? Quote Link to comment Share on other sites More sharing options...
kgallen Posted March 20, 2022 Author Report Share Posted March 20, 2022 It arrived a few days ago. The plot thickens… Quote Link to comment Share on other sites More sharing options...
BearBoy Posted March 21, 2022 Report Share Posted March 21, 2022 Have you had a chance to check out what they've sent you, @kgallen? Quote Link to comment Share on other sites More sharing options...
kgallen Posted March 21, 2022 Author Report Share Posted March 21, 2022 So I picked up the box from the post office. Right sort of size. Customs Description ‘Car CD Player’. Go to work… Get home and unwrap it. Very well packed. And it is indeed an MD drive, and the right one. It looks new and it looks Sony. But there are some ‘extra’ bits. The sort of bits that should be attached. Plastic bits. And they aren’t all there. The bits that are broken are the clip at the rear and one of the side pegs that runs in the vertical guide channel. So do I just bounce it to Ali Express and start again? I guess I should have. But does it even work? How likely is that. Fit it into the MXD-D4 and support the wobbly bits. Insert a disc and immediately realise my error in the rush. The load belt is perished. The disc is in but it’s not coming out. Turn on. By some miracle it reads the disc and will play. 😃 (at this point I’m regretting starting this on my phone!) …to be continued… (not really sure why I’m writing this story like this, sorry!) Quote Link to comment Share on other sites More sharing options...
BearBoy Posted March 21, 2022 Report Share Posted March 21, 2022 The serial format makes it more exciting, @kgallen 🙂 So what happens next? Quote Link to comment Share on other sites More sharing options...
M1JWR Posted March 21, 2022 Report Share Posted March 21, 2022 drive main body is no good now, once thyat clip at the back is broken it is fubar'ed you will have to send it back also you have the kit to make a good one out of the pair of them choices choices Quote Link to comment Share on other sites More sharing options...
guyser Posted March 23, 2022 Report Share Posted March 23, 2022 I bought the same one, the only problem I had was of course the belt was no good. Replaced it and put it in a MDS-E10 , and it works peachy. Complained to Ali-Express about the belt since they advertise it as new, and asked for $30 back and got it. I suspect it is just pulled out of another unit. Quote Link to comment Share on other sites More sharing options...
kgallen Posted March 23, 2022 Author Report Share Posted March 23, 2022 Yea, I’m probably not tough enough with these sellers! They are clearly NOS (at best) not truly new. Anyway in my case, out came the Araldite and some plastic parts cut from some old electronics… rebuild a new rear clip… Quote Link to comment Share on other sites More sharing options...
M1JWR Posted March 23, 2022 Report Share Posted March 23, 2022 fingers crossed for a well done on that kevin Quote Link to comment Share on other sites More sharing options...
kgallen Posted March 25, 2022 Author Report Share Posted March 25, 2022 On 3/23/2022 at 2:27 AM, guyser said: I bought the same one, the only problem I had was of course the belt was no good. Replaced it and put it in a MDS-E10 , and it works peachy. Complained to Ali-Express about the belt since they advertise it as new, and asked for $30 back and got it. I suspect it is just pulled out of another unit. I'm intrigued about the actual drive that was advertised and you received. The E10 takes the MDM-7SC variant. In this story I bought an MDM-7X2A. What did you get (if you know how to identify them)? If it's an MDM-7X2A are you saying it actually works ok in an E10? It's quite possible it will as it is a good match as Type-R/ATRAC3 using CXD2662. But I'm interested if the "high speed"-ness of the 7X2A has any side effects in the E10. Maybe not as probably it's only switched in to do 4X CD dubs, which the E10 obviously doesn't have as a stand-alone MD deck. In addition as the E10 will ignore SCMS on a record - and on the E10 PRO model allows you to set the recorded SCMS bits - I'm assuming neither of these work unless you actually got an MDM-7SC drive. From PCB photos alone it's not possible to determine a 7SC versus other MDM-7 variants unless you can see the sticker that usually has "SC" somewhere on it. I would say the MDM-7X2A I got was NOS. In the machine it reports 15minutes of OP time, which would be consistent with the amount of testing I've done with it. I realise that the odo counters can be reset but I don't think the seller is that knowledgable (since I'm pretty sure they don't actually know what they are selling, although clearly they realise they have considerable value based on the price I paid...). Darn, I'm leaking my soap-opera story... Quote Link to comment Share on other sites More sharing options...
kgallen Posted March 25, 2022 Author Report Share Posted March 25, 2022 All right I'll cut to the chase. It's only that I was typing my initial story on my phone and it was late that it became this nonsense serial thing! So I rebuilt that clip on the back. Of course because I didn't have the upper disc sled in place, it broke straight off when I tried to fit the top. So I did the reverse and fit the top then fit the new clip structure I made around it and reglued to the main plastic body. Left it to dry for a couple of days. If I need to replace the belt again, I'll need to use @M1JWR's method and go fishing through the front (since I usually lift the bonnet [hood for you Yanks]) and fit the belt from the top. Initially I couldn't record a whole album, I got a Record Error after a while. Investigating, the laser sled got stuck at mid and wouldn't traverse to the outer edge. Even winding the gears manually I couldn't get beyond mid. I greased the sled rail and that didn't help. I worked it a bit manually and eventually it started moving ok. My concern was there was some of the broken clip stuck inside the mech, but I couldn't see anything and I couldn't get anything to drop out. I'm certainly not going to try and separate the BD board from the rest of the drive. But I do need to keep an eye on this in case there is something in there that has just happened to move out of the way temporarily. In the machine (geez it stinks!), now it's working perfectly. I've dubbed much of a CD album and it seems to work fine in both Normal (1x) and High Speed modes (2x MDLP, 4x SP) so it seems pukka. Service Mode settings seem consistent - Iop Compare reports 0% OK which is the first time I've seen that so it suggests the OP is indeed unused, and the OP rec and play times are consistent with the number of minutes I've played with it. Conclusions: - I suspect I got mostly lucky with what I received. It was pictured as an MDM-7X2A which is what I needed and to my surprise is what I got. OK it was a bit broken and this is down to the seller not inspecting before shipping. Maybe the've just got a box full from some end-of-run sell-off from the Sony factory when they ceased production (these machines were made in Malaysia rather than Japan). That there were some bits of the clips not inside the (Sony?) bag means it was broken before it was shipped. Maybe the side peg was broken during shipment because the rear clip was broken so the disc tray was flapping around on it's way across the globe. - It doesn't make any financial sense. I paid £70 for the broken MXD-D4 and the drive cost £84 delivered. The machine is probably worth £75 on a good day on eBay (It's a decent machine with CD+MD so they should be worth a bit more to my mind). There's one on there now at 70 quid spares/repairs. No I'm not... - However if you have a beloved machine and you need a new drive, maybe there is light in that you may well be able to get a NOS drive for it. Just remember to replace the load/eject belt straight away! Other things I needed to do. - Needed a new 27-way FFC cable. The one in the machine was damaged at the end, possibly me inserting and withdrawing repeatedly. The replacement wasn't the quality of the Sony original. Comparing side-by-side the Sony one is definately a more substantial construction. However the replacement one, which is probably standard part fodder these days, is working fine, it's just a bit more flimsy so probably won't tolerate much in-and-out like the Sony originals do. - I needed to strip apart and clean the headphone volume potentiometer because it had a drop-out mid-travel and was a bit rough at the ends. I couldn't find new the correct Alps part - looks like a Sony special [*]. So ended up stripping it down and using some Deoxit Fader F5 to clean it. Rebuilt and reassebled and is working fine now. - The CD mech is a little noisy, but I've added some Molykote grease to a few gears and it's less noisy now. - Oh and I renewed the power flex and fitted a new plug. I might use this unit to play with my SPDIF/TOSLINK project before I inflict it on great fellow enthusiasts @BearBoy , @M1JWR , @sfbp. [*] The volume control is an Alps RK09L series. However the one in the machine is 1kOhm and because the PCB is mounted vertically, the spindle flat is at 10 o'clock and also the flat section is full length of the spindle. Alps standard parts start at 10kOhm and the spindle flat is at 2 o'clock for horizontal PCBs and isn't the full length of the spindle. (sorry for the shonky photos) Quote Link to comment Share on other sites More sharing options...
BearBoy Posted March 26, 2022 Report Share Posted March 26, 2022 Good work getting everything working @kgallen I could do with a spare MDM-7S1A. I've been keeping an eye open for a cheap 480 but they not so cheap these days... Not sure whether your experience gives me the confidence to try Ali Express as an option or not 🤔 Quote Link to comment Share on other sites More sharing options...
kgallen Posted March 27, 2022 Author Report Share Posted March 27, 2022 20 hours ago, BearBoy said: Good work getting everything working @kgallen I could do with a spare MDM-7S1A. I've been keeping an eye open for a cheap 480 but they not so cheap these days... Not sure whether your experience gives me the confidence to try Ali Express as an option or not 🤔 Be careful. There is a seller claiming to have drives for a 480 but you can just see the paper label says X2AS plus the EMC shield and 90MHz crystal so it’s an MDM-7X2A (Type R/MDLP) as I bought, not a Type S. As you say you need an MDM-7S1A drive. Quote Link to comment Share on other sites More sharing options...
kgallen Posted March 27, 2022 Author Report Share Posted March 27, 2022 Here are the listings for various MD drives I can see on Ali Express, not necessarily as described as discussed above. The first is the one I ordered. Clearly some of the other listings are not what they say if the photos are correct. ￡74.21 | Original new KMS-262A KMS-262B KMS-262E KMS-261A KMS-261E KMS261A KMS-261 KMS261E KMS261 Laser lens for SONY MD https://a.aliexpress.com/_mq1LdVy I don’t believe this is really an MDM-7S2A: ￡77.64 | Brand new and original MDM-7S2A MDM7S2A KMS-262A KMS262A md laser lens for MDS-JE480 MDM-7S2A player https://a.aliexpress.com/_m0Qg9KO ￡78.18 | Original new MDM-5A completely mechanism for MDS JE500 - MDS JE510 - MDS JB920 MD player https://a.aliexpress.com/_mNukII2 From the pictures this looks like an MDM-5A (ATRAC1 4.5), it’s definitely not an MDM-7 series because they aren’t all metal (even in Pro decks): ￡93.44 | Original new KMS-260A KMS-260E KMS260A KMS-260 KMS260E KMS260 Laser lens for MDSJE480 SONY MD https://a.aliexpress.com/_mN7Ii50 Possible legit laser plus OWH? ￡50.43 | Original new KMS-262E KMS-262 MD Laser lens with Recording head https://a.aliexpress.com/_mL7XRPs Quote Link to comment Share on other sites More sharing options...
BearBoy Posted March 27, 2022 Report Share Posted March 27, 2022 54 minutes ago, kgallen said: Be careful. There is a seller claiming to have drives for a 480 but you can just see the paper label says X2AS plus the EMC shield and 90MHz crystal so it’s an MDM-7X2A (Type R/MDLP) as I bought, not a Type S. As you say you need an MDM-7S1A drive. Yeah, when I looked yesterday that was the only one I could find and, like you say, the numbers don’t align. Thanks for the links. I’ll have a nosey around. Quote Link to comment Share on other sites More sharing options...
kgallen Posted March 27, 2022 Author Report Share Posted March 27, 2022 I’ve ordered another 🤦♂️ I need a laser for one of my E12 and a laser alone is more than £60 delivered (Ali Express and eBay) so I thought a whole drive will give me lots of spare parts and in theory a guaranteed working laser and OWH (based on Techmoan’s experience with his SACD of just buying the laser). If this one arrives intact then maybe I’ll use that in the D4 and strip the one I have for parts. This time it will be a laser change as the E12 has the MDM-7SC drive… Will keep you updated… Quote Link to comment Share on other sites More sharing options...
M1JWR Posted March 27, 2022 Report Share Posted March 27, 2022 On 3/26/2022 at 4:16 PM, BearBoy said: Good work getting everything working @kgallen I could do with a spare MDM-7S1A. I've been keeping an eye open for a cheap 480 but they not so cheap these days... Not sure whether your experience gives me the confidence to try Ali Express as an option or not 🤔 there you go bearboy https://www.ebay.co.uk/itm/194941022121?hash=item2d6363efa9:g:SNUAAOSwrIxiQID0 Quote Link to comment Share on other sites More sharing options...
BearBoy Posted March 27, 2022 Report Share Posted March 27, 2022 Cheers @M1JWR. I'll keep an eye on that one. I'm always a bit nervous about stuff sold for spares/repair as you've got no comeback if the bits you want are the bits that are knackered. If it stays cheap it might be worth taking a punt though. Quote Link to comment Share on other sites More sharing options...
kgallen Posted March 27, 2022 Author Report Share Posted March 27, 2022 Are you after any part in particular @BearBoy or just a drop-in spare drive for the future? I'm wondering if in a year or so people will get bored of their ‘new’ machines and start flogging them off again. Prices are sky-high on eBay-UK at the moment though. I’m glad I got the machines I need (thinking of my E12 machines I use for shows) when prices weren’t stupid like this! Quote Link to comment Share on other sites More sharing options...
BearBoy Posted March 27, 2022 Report Share Posted March 27, 2022 I’m after a spare drive. One of my 980s is a bit temperamental. I need to pop the lid off and give it a clean etc but as the prices for those head ever upwards I thought it sensible to have a working drive in reserve. You do wonder if the current prices will be sustained in the long run. There’s obviously a limited amount of stock but, as you say, I wonder how many people will find a new hobby to occupy their time and start selling them off? Quote Link to comment Share on other sites More sharing options...
sfbp Posted March 27, 2022 Report Share Posted March 27, 2022 Not meaning to sidetrack the conversation but jumping in here - "temperamental" can come from over heating. Overheating can come from incorrect adjustment. "just" (how I hate that word) a thought. Quote Link to comment Share on other sites More sharing options...
BearBoy Posted March 28, 2022 Report Share Posted March 28, 2022 I don't think it's likely to be overheating in my case as it would happen from when the machine was first turned on. Having said that, I've no idea how quickly these things heat up! I'll dig it out some time this week and have another play around. Quote Link to comment Share on other sites More sharing options...
sfbp Posted March 30, 2022 Report Share Posted March 30, 2022 Well I definitely saw overheating on my 100V (Japan model) CMT-PX3 which has an MDM-7X2A, when plugged into 120V. When it (the drive not the whole machine) came back from Jim, I made sure to get a 100V converter and it's worked a treat ever since. I know there can be variations in mains voltages, when I was at school we had our own generator and my Tandberg tape deck just about died when the voltage went to 190V on a Sunday afternoon (everyone was trying to use electrical power). Quote Link to comment Share on other sites More sharing options...
kgallen Posted March 30, 2022 Author Report Share Posted March 30, 2022 Regardless of the line voltage the internal supplies to the electronics are low voltage and regulated. Excessive ac line voltage (say a 100V machine on 120V) will cause additional heating in the power transformer and additional power dissipation in the linear regulators because their input voltage is higher but their output voltage is fixed. Power dissipation is voltage drop times current. However the internal electronics are running on regulated rails, the main ones being 3.3V and 5V plus something like +/-8V for the analogue. So their power dissipation won’t be any different. Quote Link to comment Share on other sites More sharing options...
BearBoy Posted March 30, 2022 Report Share Posted March 30, 2022 On 3/27/2022 at 10:45 PM, sfbp said: Not meaning to sidetrack the conversation but jumping in here - "temperamental" can come from over heating. interestingly, I've had some issues today with my SACD player being "temperamental", which could be temperature related. To avoid dragging this thread off topic I'll post about it in the CD player thread: Quote Link to comment Share on other sites More sharing options...
sfbp Posted March 31, 2022 Report Share Posted March 31, 2022 On 3/30/2022 at 12:20 AM, kgallen said: Regardless of the line voltage the internal supplies to the electronics are low voltage and regulated. Excessive ac line voltage (say a 100V machine on 120V) will cause additional heating in the power transformer and additional power dissipation in the linear regulators because their input voltage is higher but their output voltage is fixed. Power dissipation is voltage drop times current. However the internal electronics are running on regulated rails, the main ones being 3.3V and 5V plus something like +/-8V for the analogue. So their power dissipation won’t be any different. I bow to your electronics knowledge. I do remember Jim explaining how the various different versions of (at least) the PX3 were only separated by something he called a "backstrap" - the idea being that to get to/from 100V/120V there was a sort of feedback loop where some (7% IIRC) of the (transformed) voltage is either added or subtracted to the AC before conversion to DC. In the confined space of the bookshelf models perhaps this makes more difference but I definitely remember both the drive and MDs removed from it getting warm as a sign that the drive was about to fail. You're right, it could be coincidence but ever since I have made sure to run 100V models on one of the transformers (rather than attempting to modify the circuit since we never have succeeded in finding any Japanese-language service manuals at all that definitively show the internal arrangement) intended for Japanese-market products. Snake oil? Perhaps but I don't think so and there are those here who may have experience with the 100V converters. Sounds quite reasonable to me that a misadjusted MD laser mechanism might be a sort of heating feedback loop that cooked the device (slowly). Quote Link to comment Share on other sites More sharing options...
kgallen Posted March 31, 2022 Author Report Share Posted March 31, 2022 Since minidisc machines were sold around the world, often the mains transformer used has all of the primary taps required for all regions and the selection of input voltage is made either by a switch on the back (not common due to cost) or links on the PSU circuit board. You might find that a simple link mod in your (mid- to high-) machines can change them from 100V to 120V (or 230V). However it's also possible that for the low-end machines or high volume machines they used a custom transformer for the region to minimise costs. Service Manual and/or PCB inspection required! Nice to have you back @sfbp🙂 Quote Link to comment Share on other sites More sharing options...
kgallen Posted March 31, 2022 Author Report Share Posted March 31, 2022 On 3/23/2022 at 2:27 AM, guyser said: I bought the same one, the only problem I had was of course the belt was no good. Replaced it and put it in a MDS-E10 , and it works peachy. I was just thinking about this... you must have bought a different drive to me. The MDM-7X2A has a 27 pin ribbon and then a 17 pin ribbon. The MDM-7SC, like the "normal" Type-R/MDLP MDM-7A has a 23 pin ribbon on that second connector. So the MDM-7X2A I bought wouldn't fit (electrically) into an MDS-E10... Quote Link to comment Share on other sites More sharing options...
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