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kgallen

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Everything posted by kgallen

  1. Hopefully my description of the steps is good enough without the video? Please shout if you need more clarification but hopefully with the drive in front of you it should be clear. (Also apologies I doubt I’m 15 miles from you, I thought I was replying to another member close to me!) Kevin
  2. Well done! Sorry other than a bad connection I couldn’t think what could cause this. Badly seated ribbon cable would have been my only suggestion. Glad you’re sorted now and the eject works. Thanks for letting us know! Kevin
  3. Ramblings of an Addict. My wife is laughing at me. At the weekend I recorded my first LP (MDLP) discs... At work I can't get any indoor radio reception (even if I had a portable) and our IT department can't decide whether I can access online BBC radio or not (sometimes it works, mostly it doesn;'t). Basically this means I use my MZ-R700 a lot at work to listen to my largish stock of MDs (dubbed CDs, recorded radio documentaries and the like). I'm desk based, so having a stock of MDs in my desk pedestal drawer is not an issue. At the weekend I was in our local town with the intention of getting my hair cut. There was a queue of gents waiting so I thought I'd have a wander around our (small) town a bit to while away a little time and I don't get there that much so it's good to have the odd wander. I ended up in one of the many second-hand shops (I think they use the word "antiques" quite a lot), having a rummage around in the back dusty quarters. When I'm about I like to have a little look in such shops in case any MDs (discs) turn up. Well you can never have enough can you. As ever, they didn't have any (although I mentioned such to the proprietor who at least commented that she'd heard of them). As it was I ended up looking at a few compact cassettes. I have no outward love for this format, but as it happened a couple of months ago I rescued a Tascam 112 cassette desk from the skip at our local hall where we do our theatre shows, and with a little love I've got it working nicely. Not that I have any specific use for a cassette deck, I just hate seeing good quality equipment go into landfill when all it needs it a little "fix" attention. Well I happened across a couple of audio books - voicings of two books behind a popular comedy series from back in the day here in the UK. Two books from Red Dwarf, one read by one of the main stars and the other by the author and TV director. Each comprised 4 cassette tapes in "as-new" condition. Said proprietor wondered where on earth I found these things in his shop, and being unable to raise change for my 10 pound note he proffered them free of charge. Well I like a bargain as much as the next man, but I'm strangely unhappy taking goods from a shop without any payment, so we agreed on the price of 2 of my finest British pounds which I would return with once I had broken my tenner. Subsequently finding the barbers still busy I wandered again and having broken my note with a small purchase returned to the aforementioned shop to settle the agreed payment. At which point, the proprietor being busy with another customer surveying his vast selection of silverware, I retired to the rear of the shop to see what else I could find. This ended in the purchase of a set of CDs for a very small number of coins. Setup was my weekend to get these dubbed onto MD to replenish my catalogue for use at work. The remains of the weekend was spent with the Tascam 112 and my newly rejuvenated MDS-E10 (see elsewhere in this forum!) to do the cassette-MD dubbing and my Tascam MD-CD1 for the CD to MD dubs. The audio books. Well, how many discs was I going to need and was the split of cassette to MD going to work. Retrieve my stock of MD blanks and consider my collection of 74 and 80 minute options. Anal am I that I wanted each "book" across the same type/colour/size of MD so my filing looks nice. Length of the first book, 5 hours across 8 sides of compact cassette. The second book, 5.5 hours also on 4 cassettes. Hmmm 300 minutes. Hmmm how to split that into 74 or 80 chunks coincident with the cassettes - otherwise I was in for a weekend of faffing around with the partitioning of cassette onto MD. Hold on. 80 minute MD. LP4. Debate with the wife that four 80's are 320 and 5 hours is indeed 300 minutes and we haven't both forgotten simple arithmetic. Dang it. The whole book is going to fit on ONE MD!!! One! OK, the second book might be marginal, but the cassette liner did say "approx 5.5hours". Well that is 330, so I might be lucky. I was. Quite a few hours later I have ONE LP4 MD with Red Dwarf "The Last Human" and another with Red Dwarf "Backwards". How happy am I. Small things. I never did get my hair cut. That's a job for this weekend. Unless...
  4. Pop the lid off and let us know how you get on. Meanwhile keep an eye out for a 480.
  5. Yep, that's one of 'em. Do you want to go down this route? If we find the OWH is open circuit, for all practical purposes we swap the drive. If the OWH isn't open circuit, then there is a fault in the drive circuit. For all practical purposes we swap the drive. If one of my machines had this problem, I'd probably try and diagnose it more, but only for simple issues like there was a lose or broken wire, or the lead wasn't plugged into the PCB. After that, I'd swap the drive. Kevin This is a picture of the overwrite head assembly. It's on the top of the drive. The OWH head itself is a tiny patch on the underside of the end. There are two metal strips that run the length of this moving assembly. Checking continuity (with the unit OFF!!!) between these two metal strips would determine if the OWH was open circuit. But there probably is no real benefit of going there! There will be two black wires that come out lower down, terminated in a 2-pin connector. Check this is mated ok with the other part which is soldered to the controller PCB. You can do all of this with just the lid off, no need to remove the drive itself. The drive might have a metal cover over the rear of the drive - they do that on the expensive machines, but leave it off on the cheap ones! There are 4 screws to remove the cover but this east easier with the drive out. NEVER have the machine PLUGGED IN with the lid off. The laser is invisible and can blind you instantly. Also there are exposed parts a full mains voltage even when the machine is "off".
  6. Exactly, for the reasons you say - cheap and perfect donor into a nicer machine. Easy-peasy to swap the drive. Lid off, 4 mounting screws, 2 ribbon cables, maybe a chassis lead. Pop the new one in, reverse the above. Happy days. Kevin ps I know the 980 is a little "fancier" (and I don't have one) so the drive might be embedded in the chassis assembly more, but all of my machines are as easy as above. pps I've just downloaded the Service Manual, and from the assembly diagram it does indeed still look as simple as the above. Some machines I think have sliding trays (not sure which models) and these might be quite different.
  7. Sounds like an overwrite head (OWH) issue. The "making a disc blank" issue in the 980 is probably because the laser is still working during recording and heating the bit position to the Curie point, but the OWH is not providing the polarising magnetic field which orients the bit to encode a digital "1" or "0". This is the "magneto" bit of "magneto-optical" (MO) drives, minidisc being a classic example. If you have a DVM, first step with the machine OFF and the lid off is to do a continuity check on the overwrite head. Poke me if you need more detail. Second step is to find another machine with the same drive and do a transplant! The drive in a 980 is an MDM-7S1A and these are (only) found in the 480, 780 and 980. You might be able to find a cheap 480 on eBay. This is not so cheap (£50), but "cosmetic damage" is what to look out for as a donor machine as long as it's otherwise listed as working. Then strip it for parts like the drive. https://www.ebay.co.uk/itm/Sony-MDS-JE480-MiniDisc-Player-Very-Heavy-Cosmetic-Damage/324036319093?hash=item4b7211d775:g:tL8AAOSwljFeFf9g
  8. Belt change is easy. There is some debate on the belt, but I've had success on several MDM-7-family drives with 17mm belts from a UK eBay supplier. YMMV. This is a long 'ole thread but pretty much everything you could need is in there. I chirped in quite a lot and Charles Holt's ebay link is in there somewhere for the belts. The drive in this thread is the MDM-7SC which is mechanically identical to your MDM-7A. For belt replacement I propose my method of access by lifting the top of the mechanism although 2many prefers the keyhole surgery method. "My" belt replace recipe: If you can't find a 17mm belt online, PM me and we'll sort something out. After all, I'm within about 15 miles of you...
  9. If the JB drive has two earth leads on the MDM then transfer these over to the donor drive. I referred to them as flying lead to avoid the "technical term" earth strap. They are there for audio reasons. The 4 rubber bushes and the shouldered screws are unique to the chassis design and set the correct height of the drive to the loading slot. So you need to use the rubber bushes and shouldered screws for the JB in the JB. Kevin
  10. Stephen is being over generous with his recommendation! However yes, both decks use the MDM-7A drive so go right ahead and put the 470 MDM into the JB. Use the drive only. Keep the two ribbon cables and the mounting bushes of the JB in the JB. There might be a chassis flying lead on the 470 drive. If there isn’t one in the JB then just unscrew the lead and leave it off. You don’t need to change any service settings! Just swap the drive and give it a go. Once you have a working JB then we can put the ‘bad’ drive in the 470 and mess about with the laser if you feel inclined. If it goes all wrong we’ve only lost the ‘cheap’ 470. There is an exact match of MDM so there should be no electrical issues here. I’ve had success with some slight mismatch. For example a 480 (MDM-7S1A) works in an MDS-E10 (MDM-7SC) but a 440 (MDM-7A) doesn’t. (ETA IN hind sight this might not be true it’s possible I got both types to work in the E10. I have documented this in one of my long rambling threads on here somewhere.) Buying a cheap donor deck is the easiest way to save a higher end model when the drive is at fault. Typing on a phone for now (yuk). I’ll check back later (UK time). Kevin
  11. Sony part 4-227-025-01 if you can get it. Otherwise I believe we concluded 17mm diameter by 0.8mm cross section square. This is 54mm circumference. I’ve been using 17mm x 1.2mm non-genuine parts but this hasn’t always worked for all members, or me. ETA 20/Dec/2020: On an MDS-E12 I'm repairing now, 17x1.2mm hasn't worked for me; the drive struggled to load and eject. I ended up using an orthodontic band of a narrower gauge [9.5mm (3/8") 2.5oz] (although diameter of <10mm which is not ideal) which seems to be working nicely now. The original belt I've removed which is loose is measuring 19mm by 0.8mm square section. So if anyone can find a reliable supply of 17mm x 0.8mm then they should be perfect. Good luck! Kevin
  12. Humph. How can I be using MD so much and not know about Minidisc day! (Before seeing Techmoan's video that is). Thanks for starting this topic! For the record, whilst typing this, listening to Level 42 - True Colours on my MZ-R700...
  13. Aha, just published, thanks! (Thought you might be a Patreon priority customer!).
  14. A bit more hair, slightly less chubby and worse clothes-sense :-D Ah, so you've worked out it's an MXD-D5C he has then... I couldn't zoom in to see any model badge!
  15. Doh! You’ve all been here before in spades without my daft input! Great articles on the D40 and D5C guys! ...and I’ve learned Sony did some MD/CD combo decks - daft of me I should have realised they would - maybe they weren’t available here in the UK? Techmoan seems to have one from Japan that hopefully he’ll do a YouTube on soon.
  16. Often the PCB is the same for machines in the same range and the components are not fitted and the case is not drilled for the lower machines. When that's the case, then assuming the correct parts can be sourced, then the "upgrade" can be relatively simple for those with some electronics skills - the main PCB is removed, maybe some link wires there to remove, then solder in the new components and drill the case. I don't know if this is the case for the MXD-D40 (I'll see if I can find a Service Manual). Where the PCB is not like this, then if the unit already has a coaxial output, then adding an optical output is in theory relatively straightforward again if you have some electronics skills. The S/PDIF optical drive signal is the same as the coax one , it just needs buffering then connected to an LED-based optical TOSLINK transmitter. It's the sort of circuit that is feasible to assemble on a small piece of Veroboard or similar. Kevin Here it is: https://www.minidisc.org/manuals/sony/service/sony_MXD-D40_service_manual.pdf (as ever with Sony, this is a well drawn an "clickable" schematic). It looks like they use S/PDIF internally both from the MD and the CD sections. These are input to the D/A converter IC300 on pins 15 and 16, internally multiplexed (select 1 of 2) on to the D/A section to generate the required analogue out. Schematic pages 60 and 62 and IC307 pin 12 looks of interest (S/PDIF for the MD output)... Unfortunately it looks like this is not a sub-populated PCB with the component locations ready to fill, so would need a little more work along the lines of my second paragraph above. Looking at the SM for (e.g.) the MDS-JE520 (just 'cos I have one) it looks like the optical output LED is driven directly from the MD decoder ID. Given the D40 has IC307, I think I'd be looking to see if the spare NAND gate could be used as a buffer (IC307 looks to be there because the control micro can mute the two S/PDIF streams via the NAND gates pin 1 and pin 13). The polarity of the signal would need to be confirmed to make sure an inversion was not introduced (NAND will do a logical inversion). I guess if you know any electronics most of what I've said will be self-evident, so I've probably not helped much here in the end... Conclusion: Readily do-able if you know a bit of electronics, and it would be just as easy to put an optical output on the CD section too - the signals are S/PDIF already, the MD is on IC307 pin 12 and the CD is on IC307 pin 4.
  17. Interesting to know! I was after a power supply for my B10 and it turned out cheaper to buy one in a bundle with the N505 (although the N505 wasn’t listed as faulty...!). I did do the ‘upgrade hack’ on the N505 but as you say this doesn’t make up for cheaper build quality! Hack: http://minidisc.org/mzr700_to_mzr900.html
  18. I have a similar issue with the same model. The headphone jack is very dodgy. I have to insert the headphone plug (no remote) just right to get any sound, but even then it’s an unreliable connection. Could yours be similar? I followed the Service Manual to open mine up and resolder the headphone part of the connector. This maybe helped a bit but it’s still not good. I couldn’t find a replacement part (combined 3.5mm plus remote) anywhere (or my google-foo deserted me). Kevin
  19. I've looked at the MD-350 SM I have. The image of the schematic is very poor so I can't see all of the details. But I can see that the spindle motor is indeed driven by channel 4 of a H-bridge driver. From the output to the motor there is a series 100uH inductor and 0R link resistor and a parallel cap (maybe 10uF). The control input to the H-bridge driver comes from the CXD2662R (Sony MD DSP chip). So if there is any chance you can back-trace your unit and find something similar, I'd check the continuity of the L and R. If you have a 'scope then pins 93 and 94 of the CXD are the spindle "reverse" and "forward" drive outputs - you should expect to see pulses on these at probably 0V/3V3 logic levels.
  20. No service manual on this page: https://www.minidisc.org/part_Tascam_MD-801P+801R+801RMKII.html It might be worth downloading service manuals for other Tascam MDs as at least one is likely to share the same MD drive. There is a time-line list at the top of the page linked above. The display looks like the one on my MD-350 so that might be a good start. On Sony machines I think the spindle motor is controlled from the main board. Not sure if this is how the Tascam units do it. However I expect you’ll find Tascam use a Sony chipset (CXA and CXD chips) so the design partitioning is probably similar. Tascam probably have their own motherboard microcontroller software though (Sony would never have allowed so many bugs/quirks in my Tascam MD-CD1!). Not sure what your electronics experience is. I believe the electronics for the spindle motor are fairly simple - spindle speed control is needed but not the same level of servo control as the laser positioning. There is usually a micro control output and a H-bridge driver to the motor. Check the motor continuity and use an oscilloscope on the micro control output on the main board to look for it changing. I realise this does require schematics but a SM for one of the other machines might get you a lot of the info required.
  21. What a great forum guys! Good job all!
  22. OK, so I've cheated now. But don't think this is the last of it... So I picked up another E10 at a reasonable price (*). Cosmetically not perfect, but I just transplanted the main board from it into my not-a-happy-bunny E10 chassis, so now I have a working/nice condition E10 to add to my ever growing range of MD decks! (*) I don't really want to revisit this. The E10 arrived and I plugged it in quickly as dinner was served... Well the transformer grunted most unfavourably at me and I turned it off quick. Damn, I've bought a duff I thought. Only to find that the berk who shipped it to me (in the UK to me in the UK) had it set to 120V (cf UK 230-240V mains) and the fool in me in my rush to give it a whirl before dinner hadn't realised it had a voltage change switch (some don't) and I hadn't checked. It was set to 120V. Changed it to 240V and nothing. No display. Great, I thought, I've just blown the darn thing up straight away. Opened it up to check the 1A 20mm glass fuse - intact. Damn, could be a thermal fuse inside the transformer - well that would make it WEEE at best. Spent some time faffing with it - compared the transformer voltages against my other E10. Look good, maybe it's ok...Took the PSU and swapped it into my other (not happy) E10 and the PSU seems to be fine. Lucky boy. OK so maybe I've blown the regulators on the main board, or even the fluorescent display (which take an unregulated 42V ac from the transformer, which with my AC setting mistake could have been 80V+). Swap the main board into my other E10 chassis - and it works! Phew! Swap it back and it works! It seems the fluo display ribbon cable wasn't originally seated properly - could be the thing that actually saved the display from my over-voltage mistake! So end up making a good E10 with the original PSU, the newly-acquired main board and MD drive, and all is well. So the main board from the original E10 is sitting there in the tatty chassis until I have the energy to try and debug it more. So... let that be a lesson to us all. Check the voltage selection switch before plugging it in! Here endeth this tale...
  23. Due credit is really to sfbp who pointed me at this document a few months back, and the people at minidisc.org for hosting it. However it is good to know where a "backup" is should minidisc.org hosting disappear!
  24. It’s all explained in this Sony document: http://minidisc.org/manuals/minidisc_training.pdf Your specific query on the coding holes is explained with diagrams on page 2 (page 5 of the pdf). Also page 12 (page 16 of the pdf). Enjoy! Kevin
  25. Could be a dry bearing in the direct drive disc motor although I’ve never come across that before. Have you tried other discs? I have noisy ones but probably not a squeal noise. Re the laser, if there is a disc inserted and properly seated then the laser is under the disc (but pointing up). I’ll let you make your own assessment based on that. Certainly never look anywhere near the laser if you enter service mode as the laser can be turned on with no disc in. The laser is in a lower power mode when playing. When recording the laser is in a high power mode that pulses on for each data bit to raise that tiny disc area above the Curie temperature whilst the overwrite head on the top sets the appropriate magnetic field depending on whether the data bit is a 1 or a 0.
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