jim.hoggarth

I thought the D variant was that with no power adapter socket? But then I am on my third can of polish beer. Jim

It's a federal conspiracy - be sure to wear your tin-foil hat when recording anything!

You are very unlikely to damage the DH10P with the PS adapter. If it works, great. Otherwise you do need that extra one volt. Which country are you in? I have a box full of AC-608K's and most probably have a 2-pin Euro one somewhere. Jim

Good to know you are sorted out at last. Very odd that it was C333 - I would not have expected the problem to be on the FLD negative bias line, as it is effectively isolated from the rest of the system by the power transformer. The more usual problem here is the zener stabiliser diode going short, which leads to ghosting in the display. But, there you go - I don't know everything! Jim

No, don't short them! They act like tiny batteries, smoothing the power lines they are across. If you short them, the unit definitely will go bang! Just remove those capacitors (electrolytic type - in the metal can covered with shrink plastic) which you can see are across the power lines, one by one. Then replace each one before removing the next. On an almost purely digital unit like this, very few of the capacitors are going to be used as DC blocking caps on a signal line, so you can assume they are all smoothing capacitors. Are you confident you know what you are doing? Let me know you can definitely locate these caps, and that you can follow the power line on the schematic. Also, have you tried removing the IR receiver yet? Jim

You have a superb fault on this machine - I say superb, as in anyone with a love for electronic fault diagnosis would relish the chance to diagnose this. I hope I don't lose you here: Looking at the service manual schematics (page 56), the Play Mode, Repeat, Scroll, Power and Mono/Stereo switches are all assigned to Key 1 signal back to the master control processor. The method used is a voltage divider based on a resistance ladder, which feeds into an ADC input on that processor. The Key 1 line is tied up to 3.3v by a 10k resistor (see page 44 - pin 4 of IC316. R329 ties it up to B+ line). Play Mode shorts the key1 line to 0v, Repeat presents 2.2k to it, Scroll 5.5k, Power around 10k and Mono/Stereo around 20k when in the stereo position. When in Mono, the line is left floating and thus pulled up to 3v3 by R329. So you can see that switching into stereo is done by presenting around 2.2v to pin 4 of the controller IC. If 'stereo' appears when pressing 'Scroll', you would assume ohmic contacts on the scroll button. But that would not explain the other problems. I think this results from a bad 3.3v power line, either browning out or with a lot of noise on it. If you trace the line back, it goes to pin 5 of IC309, the switching regulator IC. You want to check for bad joints on this chip first. Or put a 'scope on this output and look for an obvious breakdown of the supply line - it will be very obvious and look just like noise. Alternatively it may be one of the other components in the system which connects to the 3.3v line, and it may be very hard to find. My first suggestion would be to disconnect the 3.3v terminal on the IR receiver chip - IC702. As I said before, I have had one instance of this failing and causing a dead unit. It may be a common problem! Another thought is that it is one of the many supply line capacitors, particularly the electrolytics. Try disconnecting these one at a time to see if the unit improves. If is does, replace the capacitor. Electrolytic capacitors do not have a particularly long life, and as this unit could be 15 or more years old (and could have done many thousands of hours 'on' time), I am sure at least one of these capacitors is one the way out. Jim

Hi. The mono/stereo flickering is simple - it is the select switch with flaky contacts. The same happens to the input select switch and to a lesser extant the timer switch. If you sort these out first , then retest the unit as spurious signals going into the IO pins of many processors can cause all kinds of weird things. The 'warming up' may well be a fault on the 'BD' board, that is the control board on the drive unit. Or it may be a laser problem. As for the third problem, the powering down is not a fault I have seen before on a JE510. Other than drive problems these are usually reliable as regards the main board and PSU. Most likely a power supply fault, but to be honest it could be anything. I had a bookshelf system once that intermittently went dead because of a faulty IR receiver. Every so often it just shorted out the 3.3v supply. But as I say, best sort out the front panel switches first and then re-appraise. Jim

Keep a look out for the M-Audio CO3. This does all you need: RCA, S/PDIF and AES/EBU inputs and outputs. Any of the three inputs can be selected, and all three outputs are available at all times. More importantly, the SCMS bit can be stripped, passed through or set. I have just done a search on eBay to try and get some prices, but none are available at the moment. I am sure you could snap one up to £50/$75 dollars eventually. Jim

Hi again Enito I have just scrapped an MDM-3B drive unit for the parts, so I have a surplus switch board if you would like to purchase it. That way you can remove the switch you need and have a couple of spares for the future. I believe this only has one fault - the chuck-in switch S685 seems to stick and the contacts may be bad, resulting in no disc load when a disc is inserted in the drive. You can have it for the cost of posting to you, plus a few GBP to cover my time and effort. Where in the World are you? Jim

Good luck. If it gets you up and running without further problems, that's great. Jim

Hi. This model has the MDM-7x drive, which is plagued by the C13 error. In my experience it is usually the spindle motor sticking, or a fault on the optical pickup, or as Stephen points out, it requires realigning. It goes like this: When a disc is inserted, the drive electronics sends the sled back to home, if not already there (which it should be!), then moves the objective lens up/down until the focus servo reports it can (at least partially) focus on a disc. Otherwise you get the message 'NO DISC'. The drive then spins up the spindle motor to max speed and tries to lock on the track. If the servo comes back with an error, or the initial data read from track zero is nonsense, that's when the C13 READ error appears. Or for some reason it can also give a C14 TOC error, but I am not quite sure why one or the other. A marginal focus alignment caused by a low or crappy laser can decide that the disc exists, but cannot then track the TOC info. Similarly, if the disc does not come to speed, the drive cannot read valid TOC info. And that's why both faults can cause the C13. If you pop off the hood and push a disc in, you may be able to tell if the disc is spinning up or not. I have a special clear disc with a black felt-tip line drawn on the upper surface of the disc just for this job. If not, eject the disc and delicately touch the spindle motor capstan (the disc that spins the disc) so that it moves slightly. Obviously if it won't rotate, the motor is totally fubar. But if it then kicks into life when a disc is now inserted, you know it is 'stiction' causing the problem. In which case it may work again for days, months or even never fail again? I have seen one particular unit that fails only once every year or so. A good jolt sorts it out for the next few months at least. Jim

Hello John Very interested in this, but with the usual post-Xmas slow down in sales I am skint at the moment. If it is still available in February give me a PM to see if I have the cash available yet! Jim

I realized that after putting up the list, then thought - no, it is very similar to the slide eject system as the push-knob is physically connected to the lid lock lever, Whereas the real push eject with problems, such as the R410, N510, R700 et al, have a button mounted on a plastic 'hinge pin' that inevitably breaks and makes opening much harder, requiring the button to be pressed much further into the body of the unit. That's what I assumed the OP to be meaning. But yes, you are right. Jim

Unfortunately, the minidisc unit is powered down when the radio is working and vice versa. 'Slide to open' Sony recorders (excluding really early units): R30 R35 R37 R50 R90/91 R500/501 R900 R909 R910 N1 B10 N10 N710 NF810 N920 NH1 NH600 NH700 NHF800 NH900 RH710 RH910 M100 M200 RH1 Not a complete list, it's off the top of my head. Lets' hope I haven't made too many errors. Jim

Hi Stephen. Just checked the JB940 schematic, and it looks like only the keyboard is supported. Two of the I2C connections from the main control processor are not physically wired up to the required pins on the keyboard DIN socket: IIC-BUSY and IIC-POWER, whereas they are in the MDS-S50. I assume but have not checked that these same connections are made on all other decks/bookshelf systems which support the PCLK-MN20. I have also checked the JB980 - no connections on these pins (pins 2 and 6 incidentally). What unit do you use with M-Crew? Is it the MXD-D40? That looks to be configured for PCLK only. Incidentally, on this model, the same I2C connection is used for inter-processor communication between the MD and CD controller chips. I have an S50 in stock now. Once I find time I will test it with both a PC keyboard and the MN20. I would love to know if it works with both. And if it does, whether appropriately connecting the IIC-BUSY (ie PCLK_DETECT) and IIC-POWER on a deck such as the JE780 or JB980 would enable PCLK features on these units. In the JB980 schematic, the system controller (IC1) has the I2C clock and data input lines pulled up to VSS through 100K resistors, and the I2C power and busy lines simply not connected. The connector to the 'keyboard' pcb even has the two unoccupied pins where these lines would need to be connected. I really do wonder... And a further aside: I see from the JB980 schematics that the USB feature was codenamed 'Unicorn'. I didn't know that before. Jim

Hi. I do have one of these in stock, but I had not planned on selling it yet as the rear case is somewhat scuffed, and the inner box was damaged by the previous user (I assume they didn't have the patience to pack everything properly, so just ripped off the 'excess' cardboard - I have seen it done so many times). Ideally I would have waited for a better remote control too, with less wear, before listing it on eBay UK. Are you after the whole package, or just the recorder? I have the complete thing here, albeit with the few problems I have stated, but it won't come cheap. I had planned, once titivated and refurbed to my usual standards, for at least 150.00 GBP - which is around $250.00 at current conversion rates. The unit on its own, without adapter (it is UK voltage), cradle, USB and optical cables, remote, discs etc? - I have not yet thought about price to be honest. Are you interested? I can provide photos. Send me a PM is you are. Jim

I currently have a few in stock, if you are desperate for one. But they are not cheap, at around 50.00 GBP apiece. Jim

I think it is about time to let you all know I have perfected the method for turning a LIP-4WM into a LIP-3WM, but it needs the old LIP-3 as well as the new LIP-4 so that parts can be removed from the old battery and fit to the Li-Ion cell of the new one. After the plastic case has been replaced and sealed with a couple of strips of insulating tape it doesn't look like a new one, of course, but then neither does it look too bad. The problem now is that sources of the LIP-4WM are drying up too. Replacement of the N10 battery is fairly easy: remove the top left case screw (the longer one), open the lid, slide the jog dial assembly upwards by a millimetre or so and it comes away on its flexible cable - which does not need removing. Unplug the battery connection, and slide the battery out. If tight (which it certainly will be after the replacement is fit), it may need help by levering with a small tool against the rubber bumper on the end. Fitting is the reverse. Remember the case lid needs to be open or neither the battery or jog dial assembly will go back properly. Replacing the MZ-E10 battery is a different thing altogether, indeed this is a task even I do not like to perform! Very fiddly procedure, and possible to actually damage the unit. The E10 was never designed for the battery to be replaced of course - the hatch is simply for removal prior to binning the unit when the battery fails. I could 'create' N10 batteries for folk if they want, for a small fee of course, but I am not sure if demand will be that great, or indeed if supply of new batteries will be consistent. At present I am buying LIP-4WM's occasionally for my own use, for N10 repairs and the odd one I purchase for resale. I have not yet got a proper picture of the long-term efficacy of these batteries, as I assume they are not genuine Sony. But the Chinese manufactured Li-Ion cells seem to be ok, at least the ones I have seen so far. I have also developed a means of replacing the Li-Ion batteries in Aiwa AM-F5, F65, F70 and F80 units, but this involves fitting of a non-removable battery using high-density foam as padding to fill the gaps. It works, but at present I have only actually done the necessary work on the F65. I see no reason why the same procedures will not work on the others, or in fact any MD unit that uses the LIB-902 original battery. The replacement is only 650mAh capacity, compared with 700mAh of the original, but that slight loss in performance is nothing compared to an old battery that only last one half hour! Jim

Yes, it could be a bad contact or cracked solder joint around the microphone input. Dirty contacts is fairly common, bad joints not so but if the input has had a lot of use? That said, I would have expected a more chaotic signal than clean on/off as the graph. Unfortunately there is no indication of time duration on the x-axis. Also seems odd that the problem is reported in Mono, not SP Stereo. A staccato signal would be the result of the laser not being able to read the track reliably. A constant signal would be played back with intermittent blank sections, which could range from milliseconds to several seconds each time. But then, the playback time would be extended to include the blanks, rather than reduced. We can presumably rule this out. Could it be the output of the R70 that is intermittent? Have you tried both earphone outputs? I am assuming you are taking the recording from one or other of these sockets, into the line input of your PC card. Have you tried the same recorded disc in the N707, does that produce the same inconsistency? In which case it is definitely the recording at fault, not the playback. Can you be sure the microphone does not have a bad connection in the cabling? Are the discs you are using good quality and in good condition, ie not dusty and scratched? Final question: Are you absolutely positive the [problem never happens in SP, only Mono? If the latter is true, I would reckon the problem is in or around the encoder, which means a main board swap. Sorry for the ream of questions, it's just easier for diagnosis if all the possibilities are dealt with in one go. Jim

Very odd. Sony did not normally keep quiet about a 'substantial' change to a unit like this. For example, the R500 became the R501 when Type-R was added, also the R700 being called the R701 with Type-R support (although on both occasions cases were also changed, not just the DSP chip). I would have expected an MZ-S2 at the least if there had been a skip from Type-R to Type-S. I would love to get hold of evidence of the change other than just the documentation, which is why I asked about an S1 with changed casing decals or legends. The second document linked to does indeed mention Type-S on page 66, but no mention on page 20 where I would have expected to see it also, when Type-R is first mentioned. Jim

Yes - if more minidisc units had a backlight it would have been a great improvement. Especially so on the hard-to-read displays such as the MZ-N1 Jim

Just had a quick peek inside my S1, which states Type-R on the plastics. It has a modified N505 type board with a 2677-204GA. Definitely not type-S so I am not sure where this talk of a Type-S MZ-S1 originated. Has anyone ever seen an S1 with other than Type-R on the plastics, rather than some possible misprint in a manual? I don't know why but I thought I would be a tad more interested and excited than I am. Perhaps it's because the glue which holds the 3v power flap rubber in place stuck to the display connector better and tore a chunk of rubber off! A warning to anyone opening theirs - you may do the same and damage the 3v inlet flap. Jim

I am 99% sure the MZ-S1 is the MZ-N510/520 in a water resistant casing. If I get time I will open up my one and only S1 and confirm, especially as there is some confusion over the type R/S status of the unit. Perhaps the S1 was designed using the N505/707 hardware, which then became the blueprint for the N510/520. Jim

The truth is, even the genuine Sony batteries have this grammatical mistake. I have seen hundreds of batteries, and every one says exactly the same: 'disposed' instead of 'dispose'. Only the NH14WM and NH10WM, though, and not the Sharp branded equivalents. Strangely, Sony's NH7AA batteries from the same era do not have this error, nor do any of the Nickel Cadmium batteries, gumstick nor AA. Jim

The only source for the specific part I know of is another drive unit from a faulty machine. As I think I said in another thread, you could do with getting hold of a scrap unit, especially as you may need a replacement write head too. Plenty to be found on eBay, just make sure the seller confirms they have not been in and attempted to repair. Jim PS - if physically broken, replace of course. But if just bad contacts, try some spray switch cleaner first.