NGY

Well, I may be, or may not. Yes, I have some experience in repairing Sony MD decks, but no other makes, and the success of a possible repair depends very much on the available spare parts as well. I happened to know this seller, so I asked privately how deep the problem is, i.e., whether the unit can properly record in MD mode, and here is his answer (also updated on the listing page, and price dropped to 35€ in parallel, though he took off the remote): ”IT DOES NOT READ MINI DISCS CURRENTLY. This needs a new MD (Hi-MD) Drive. this comes WITHOUT the remote. SPECIAL PRICE”

"ACHTUNG:Hi-MD Discs können momentan nicht gelesen werden. Normale MDs gehen aber. Vielleicht hilft eine Reinigung.... SONDERPREIS IT DOES NOT READ HI-MD DISCS CURRENTLY. ONLY MD IS WORKING. SPECIAL PRICE"

Wow, great buy, congrats. You may not want to turn it upside down, and beat - it may damage the drive, the OP and the OWH are very sensitive parts. Replacing the belt is fairly straigthforward, only four screws hold the drive in the deck, once you lifted it out, the belt is accessible from the front - via a tiny slot though, you will need to use a bent paperclip as a 'hook". I think there was a topic here, with some photos. Or I saw a video on youtube probably. I bought belts for my decks from this guy: http://www.ebay.com/itm/231770624890. This belt works for all the decks with MDM-7A drive, like your 770.

If anybody is interested: here is a very nice, hardly ever used MDS-JE640. This rare model has everything a versatile home MD deck should have: MDLP, SF-edit, pitch control, PS2 keyboard connection, coaxial and optical digital in, optical digital out, Control-A1II, etc. European 230 Volt version, made in Japan.

Yes, I am. The SM-s are nearly identical in terms of checking/adjusting, and there is no option to adjust IOP via a variable in the service menu, none of the SM-s I have read mentioned anything like that. Just checked the SM of the JA20ES, and it is nearly word by word the same, as the others'. (IOP is on page 31). Newer models have a "feature", that compares the value on the label of the OP and the value measured when adjusting the laser power, but it has nothing to do with settings, it is just a "health check". IOP is a measure, that tells how the laser diode is doing, i.e., at what electrical current can the laser emit the required light power. In practice: we adjust the laser power, and check back, how IOP looks like, whether or not it is in the factory defined range. If the laser can emit the required power only at a significantly higher IOP than its nominal value (i.e., more than 10%, or 10 mA according to Sony), that is a sign that the laser diode has (will soon have) a trouble.

Back to the post above: I see your friend knows what he is doing. If it helps you to save the machine, I can offer lending my silly little LPM and the test jig (I hope one of the three types I have will fit this drive, that I've never seen before), with basic instructions, rest is detailed in the SM. Without the battery, this fits a small and light bubblewrap envelope, and should not be expensive to mail it back and forth.

One can adjust IOP via either the pot or the laser power only - in the setup menu (I mean, that part that is public in the SM) there is no setting for IOP. "Write IOP” is just a note, to record the original IOP value written on the OP, and the result value after setting the laser power. I forgot to add this: "pot” is an abbreviation (or, electricians' slang, if you like) for "potentiometer", that is, essentially a variable resistor.

Great to see you back, and that you gave this nice unit a chance. I tend to believe the OP is on its way to give up, though it can just as well be some other causes, but from here, the deck would certainly need thorough diagnostics with the proper instruments (DVM, oscilloscope, LPM, test jig, test discs). If we bet on the weakened OP (I feel those run times are after a possible reset from previous owner/s), seeing the settings you tried did not bring result, turning down the pot on the OP may increase the level of the laser power, but it must be performed together an instant adjustment with the use of an LPM and the test jig with a DMM to avoid burning the OP out. In other words, I would not try even the smallest amount of change on the pot, if these instruments are not available. (To locate the pot, you can refer to this Service Bulletin) If we bet on the servo or the focus being out of proper settings, to check/adjust them at least a test jig and an oscilloscope should be at hand. But before that, the error rate can be quickly checked with the use of a test disc generated in the unit (as written in the SM). If the error value is high, i.e., in the couple thousands range, or, plain ”7350”, then we are back to the laser issue, otherwise a setting procedure can be attempted. OK, I see Stephen just replied while I was writing this, let me read that and then continue.

Is this the one? This is sescoscuba's site.

UPDATE: I have changed the original title "MDS-JE510 Disc Error" of this thread. I intend to collect my C13 Disc Error cases into one topic. * * * * MDS-JE510 What a silly error I faced today... Yet another 510 that came with the known troublesome load/eject. I have already fixed half a dozen of 500 or 510 with this problem (or sudden switching on from standby, or disc error upon loading a disc - as these all root in the same issue), so I performed the usual routine (fairly straightforward fix, but requires a complete strip down of the drive, and some delicate repair work on miniature parts). When completed, I put the drive back into the deck and powered up. Upon inserting a disc, I heard it spinning up, so far so good. It tried to read the TOC a couple of times, changing revolution and seeking OP, but then it spat out the disc, again with "DISC ERROR". OK, let's check the laser I thought, but both the settings and the measured mW values were spot on. Then I checked the error rate, and it was very high - increasingly higher in the MID and OUT ranges, that called for a deeper inspection. I removed the lid to take a look at the drive. It became obvious, that the disc hit up and down quite a bit, ~2 mm on the edge. I thought it was my much (ab)used test disc. With a known good disc, the same happened. First I suspected the axle of the spinning motor, whether it got bent once the last disc the deck had eaten, was pried out violently. But the shaft was running true. After trying several discs, and most of them got ejected with the error, I took a closer look at the magnetic hub that holds the disc in place, and found this: a little bulge, probably some burr left by injection molding of the part. Once I cut this little piece of plastic off, discs began running way smoother After properly adjusting the traverse and focus bias I rebooted the deck, and voila, no more disc error, and it plays/records as it should. But what bothers me, how on earth this deck had worked so far at all? Or, is it that the laser tracking/focusing mechanism did compensate for the rocking discs, but only until it got somewhat "tired"? .

Great, thanks for the info. Funny that such an early model popped up here, where minidisc was exotic and seldom.

I wonder if anybody had experience with this unit. I could not find it in minidisc.org's equipment browser (or overlooked). There are some photos on the net (like the ones below), and my understanding is that this is a fairly early model, from ’96 or so, and that maybe a close relative of the MDS-302. Was it a component of a bookshelf or desktop hifi system? It has a definite, fancy retro look. There is one advertised overhere (not the one on the photos, and it is not me, who is selling it, I just found an ad by accident).

At last, I managed to get hold of a used (apparently, very much used) 930. It was very dusty and full of (animal?) hair, the laser had run ~4800 hours, and the display was somewhat dim, but other than that, fully functional and was in a nice condition aesthetically. Plus it had the original remote too. My damage was ~100 euro, but I think it was still worth it. Now, it is time to nicely refurbish this unit, to have it look like new.

Recently I had my hands on a 480 for a short time. The odometers did work in this model, and even counting minutes, not only hours.

And this is the total current the box draws, is it? It does not look bad, but is a somewhat low value. This shows, that even if a module is blown, it is not a short circuit inside, it just smoked the silicon away. But as your LED draws about 6 mA, the rest is probably drawn by only one single module. Now, if you replace just the receiver, giving a chance that not both of the transmitters were blown. Then (1) if the current increases, the receiver was also burnt, and (2) you should get an output signal at least on one of transmitters. Should you not, then they are probably both gone.

No worries. I was doing a couple of things at the same time, this window was open for quite a while, as I could only get to it for short times, and of course the page was not refreshed. I would now check the current the device draws, as above.

You can simply cut off and file flat those lugs, they only there to hold a screw. I would not expect R1 to be blown. Red leds operate at 1,9...2,1 Volts, and, must have a current drive somewhere between 5...20 milliAmps. I took the resistor value above from these figures (Ohms law). Worst case (at highest LED illumination/current, that is not probable) it would be 150 Ohm, and when the resistor/LED path gets 9 Volts, the current running thru the resistor is still only ~47 mA, and the wattage load on the resistor is 0,33 W - even if it was only a 0,25 W resistor, still would not burn. And that the LED is still lit, shows the resistor is still conducting. The 9 Ohm you measured worries me more. It would be a better way to first desolder the anode of the LED (the one that connects to the resistor - the resistor's other lead connects to V+, while the cathode of the LED is connected to GND, the large surface on the back of the board), or just remove the whole LED. If it is still 9 Ohms on the resistor, then yes, the resistor got a damage, but the LED did too, because the lower the resistor value gets, the brigher the LED is supposed be, and a 9 Ohms resistor would allow ~300 milliAmps on the LED (at 9V Vcc), and these simple ones cannot bear that for long. But I would expect more than 9 ohms then. Anyhow, once you desoldered the LED, connect your 5V adapter, and check the voltage on the jack's terminals on the board. You should see very closely the same voltage when you just measure the adapter itself, unplugged from the board. If you are able to measure mA, then connect your DMM in series of the splitter and the power adapter, to see, how much current it draws, and if everything is in order, I would expect around 50 mA at max. But if you see several hundreds mA, then one or more of the modules are blown. Maybe not all, by trial and error you can desolder one, repeat the mA measure, until it shows only a couple of ten mAmps. I know I am still assuming a lot. But this is the case when someone does such troubleshooting remotely :-) .

Just checked on ebay: receiver, transmitter, $2,99 each + $4 shipping

I am not a whiz :-), but here are some assumptions - based on what I see on the photo (would be good to see the other side of the panel too, to confirm/deny some of them): - the sole resistor is the current limiter for the power LED, and if such, should have a value somewhere around 470 Ohm (300 ... 1K, or so), the writing on it would tell, but I cannot read it. - the capacitor is filtering out high frequency noise, I guess it is somewhere around 1...100 nF, but pretty sure it is not damaged (neither did the resistor above) - the output signal of the receiver is directly connected to the inputs of the two transmitters, and power is directly connected to the Vcc and GND terminals of the three devices. - these opto devices have some built in electronics besides the emitting LED and receiving photodiode (-transistor). There are (older) 3.3V devices, and also 5V (or 3...5V) devices, this particular splitter uses 5V ones. - datasheets of such 5V modules mostly show 6 Volts as absolute maximum rating for supply power. - your (nominal) 6V power adapter is probably an unregulated one, with a bulky transformer inside, and a simple rectifier. As the exact output voltage of such adapters depends on the load (we discussed it in another thread), with this splitter draining maybe ~20...30 mAmps only, around 7...9 Volts could probably hit the device, that could blow one or more of the optical modules. - if just one module is blown, can internally short the power leads, resulting the dim power LED, and the two others not able to operate. But these are only my assumptions, you may want to do some checks with a DMM. I saw similar devices on ebay, for about 40 bucks or so. Individual modules cost around 8...10 dollars, maybe somewhat cheaper from Far-East suppliers. Or, maybe the best, they can be digged out from old junk audio-video devices, to repair yours. But once you do that, it would make sense to build a 7805 voltage regulator between the jack and the modules, the panel/box size allows it.

You may want to try one thing, that you can perform without any special equipment. This process below is taking a chance on the read power setting of the laser (assuming there is no mechanical issue or else, that caused this C13). In other words, you can try to figure out, whether or not it is related to the laser power settings, by a careful and smart adjustment. Smartness here comes from some data, that helps you "fly blindfolded", without making any damage to the device. (I used to take notes on the settings of every single md deck I can get my hands on, and this little database began showing a nice pattern, that I can use as a reference, when working on a repair - and I refer to this data in the following). First, if you go to the service menu, and then to laser power check, the first variable is the 0,9 mW laser power setting, related to reading. This variable is displayed as $XX, where XX is a two digit hexadecimal number - take a note of it. The factory original setting for this first variable is generally somewhere between $0F and $12 (that is, four steps: 0F, 10, 11, 12), vast majority is $10 and $11. Here you will see whether this unit has a proper value, it if does, you can go further (or if it falls out of the range above, then stop there, because there probably had been some adjustments already, and without an LPM it is very risky to move forward). When adjusting the laser power setting, one step is roughly 0,045 mW (roughly, and is not fully linear, but this approximation is enough for this quick test). Try to increase the $XX value by one step at a time, save, quit, "reboot", check, if no impact, repeat. Max. 4-5 steps will not harm the laser, and should give a result, if this was the cause. If this cannot fix your C13 error, just write back the original value you took note of at the beginning, for the sake of a clean setup, if once a pro wanted to repair the unit. (One last note: when adjusting the laser power IOP also changes, but IOP can also be adjusted via the hardware, i.e., there is a trimpot on the laser head, normally set between 2,5... 3 kOhm, if it is not the case, the OP was probably tampered sometime - I left this out of the equation.)

It seems that the chance of getting any reply from him is near to zero :-( . I tried to contact him by at least three different means, still could not get thru. (Luckily, I managed to solve my questions since then, so I stopped chasing him.)

You may not need to be, just as of yet. Did you check the odometers of the unit? To get an idea of the usage of the laser head, whether or not it can be the cause for the error. Over time, as the laser weakens, can lead to read errors. (Also, as once Jim Hoggarth pointed out, a weakening spindle motor can cause a similar problem. But as yours reading the test disc OK, spindle is probably out of question.) Recently I managed to fix a couple of decks with C13, by properly adjusting the laser power and IOP. If it is the case with your unit, even if C13 was the result of the laser slowly giving up to the ghosts, an adjustment still can give you some time, before replacing the OP becomes necessary. BTW, replacing the laser with new sparepart is still doable these days (or, find a donor with a less used part), so no need to worry about that your high quality deck goes out of order for good.

I am not familiar with SonicStage (and I am not even Steven or an expert :-) ), but an MP3 format CD is simply a DATA CD, with MP3 songs written onto it, isn't it? If you use a different burning software (even Windows' built in) to generate such a (data) CD, do you get the same result?

There is a significant difference between linear and switching power supplies. Without going into deep technical details, I would just focus on one factor, that would help clarifying the confusion above - how the transformers behave in those devices. Iron core transformers have complex physics, certain losses developing inside the transformer under load, the smaller the size a transformer and the smaller the frequency of the AC the larger this effect. Linear power supplies have a transformer first, that decreases 50/60 Hz mains voltage to needed small range, then rectify and filter the voltage. One advantage is simplicity, also the low level of emitted electronic noise. Switching power supplies rectify mains voltage first, then convert this DC to a high frequency (several 10/100 kHz) signal, and transform this signal into the needed small voltage DC. One advantage is that size/weight of the transformer is much-much smaller (and way less expensive), compared to those in the linear power supplies, plus the output DC voltage is already regulated to a certain level. In those bulky looking wall adapters there are (or, used to be, for audio gear, for reasons above) mostly linear power supplies, and mostly there is no particular regulator circuitry there, as voltage regulation is done inside the device powered by the wall adapter. This is why a simple wall adapter would output a significantly higher voltage unloaded, as the nominal voltage is reached at the nominal load. These transformers are purposely designed this way, to compensate for the losses caused by expected load. Dropping from 4.9V to 3V is normal, I should say. Vast majority of modern small adapters, like those for mobile phones have a switching power supply inside, that's why the size can be such small, and why the output voltage is such close to nominal, even without a load.

A little (for me actually a big) success tonight. The mini wire-to-board plug arrived from China at last, and I could not wait to improvise the jig for measuring IOP. My LPM probe popped into the deck, jig attached to BD, DVM hooked on the jig, and there I began setting the laser. It was not that straightforward as I expected, because either the mW or the mA value fell out of the desired range. I suspect this OP underwent some improper settings in the past that wore it more than the odometers would show, as I could not fully turn the laser power up in writing mode. Nevertheless, I could set it very close to the minimum value stated in the service manual. IOP was also slightly below the -10% limit (but within the -10 mA limit, stated also in the SM somewhat contradictory, or at least inconsistently). Interestingly, read mode laser power did not need any adjustment, it was spot on. Quick check of other variables, i.e., FBIAS, CPLAY, CREC, etc. (traverse check maybe at the weekend, if I can have some more relaxed time), then I inserted a recordable MD, and hit the RECORD button. No RETRY error, seconds ticking, so far so good. Could not hold my breath for more than 10 seconds, hit stop and play. The 530 does record now! Eject, TOC writing, pop back in again, play - recorded material is there and playing back properly. I am happy that I could bring back this nice unit from read-only, also, it was a great excercise. Thanks for the support and the hints/ideas. .........