Timbo Sony Posted October 21, 2014 Report Share Posted October 21, 2014 Hello All, I've noticed with the increasing rarity of KMS260A/B lasers is pushing the price up, but the "E" version is still very cheap. It's probably only a minor difference, but does anyone know if the "E" laser version can be used in place of the "A & B" versions in decks like the 20ES, 333ES and 555ES models which are worth maintaining due to their superior performance? Perhaps the EPROM settings would be quite different compared to the original? Thanks Quote Link to comment Share on other sites More sharing options...
PhilippeC Posted October 21, 2014 Report Share Posted October 21, 2014 phamcu confirmed months ago that E can be used instead of B. If you need more technical datas, ask him directly (PM). Quote Link to comment Share on other sites More sharing options...
PhilippeC Posted October 22, 2014 Report Share Posted October 22, 2014 phamcu direct contact su_su1972 yahoo.com Quote Link to comment Share on other sites More sharing options...
Timbo Sony Posted October 23, 2014 Author Report Share Posted October 23, 2014 Thanks for the reply PhilippeC. I will contact phamcu and obtain the data. This could be a useful money saving tip! Quote Link to comment Share on other sites More sharing options...
phamcu Posted December 22, 2014 Report Share Posted December 22, 2014 It can substitute for each other on the following principles: B changed of A E changed of B E can not be changed to A, it will not work properly when recording or playback on some desk. Quote Link to comment Share on other sites More sharing options...
Chrislisa Posted May 26, 2019 Report Share Posted May 26, 2019 I have a teac h500 minidisc which i have changed the original kms 260A for a kms 260B but it searches but still will not read disc and ejects after 30 secs - after replacing the laser is there anything else i should do ? Quote Link to comment Share on other sites More sharing options...
sfbp Posted May 26, 2019 Report Share Posted May 26, 2019 Sure; you have to do an alignment. This is complicated. Don't keep trying and trying - you may well burn out the laser. All true even if you change 260a for 260a. Quote Link to comment Share on other sites More sharing options...
Chrislisa Posted May 27, 2019 Report Share Posted May 27, 2019 So have i wasted my time by removing the solder bridge and replacing the laser which i did so carefully using rubber surgical gloves - i think i know the inside and where the screws and ribbon cables all go so well i could now do it in about 10 minuites ! Is there anything I can do to check even if the new laser is working properly before i take it somewhere to align it properly. It is a shame because i really wanted to do it all myself for personnel satisfaction that i could fix it more than actually wanting it to work. However it is part of the system and looks so good. Quote Link to comment Share on other sites More sharing options...
sfbp Posted May 27, 2019 Report Share Posted May 27, 2019 Alignment refers to adjusting the voltages so that the correct amount of laser power is delivered when the circuit is turned on. This varies by each individual laser device. To give you a start, there is usually a sticker (sometimes written by hand in blue ink, sometimes printed) with a four digit number (if only 3 digits then add a leading zero) on it. This number is used as the factory pre-calibration in mA for the laser itself (how much current does it need). In many cases, setting this as the IOP value in the right place in the alignment sequence will be all you need. When it comes to adjustment, the read power and the write power are set separately, as the latter is ten times greater, roughly. So it follows that the read adjustment is more critical. IIRC the IOP number relates to the read power, but it's a while since I did all this and I was operating by guess and by golly at the time Most of this is set out in the service manual for your unit; I have no clue what the TEAC service manuals are like, having been spoiled by Sony's careful attention to this documentation. The other way of getting it right is to set up your own circuit, measure the current and (optionally) measure the actual laser power delivered. The latter definitely takes a laser power meter (cost around $200), but many service outfits get away without using one. It's the ultimate check. If you were able to do the soldering, you can probably manage this. The whole thing relies on a servo circuit which cuts in *when the disk is rotating*. It's not a static adjustment per se. Seeing that the optical pickup (OP) vibrates is sometimes but not always a sign that the power is wrong. Above all do NOT leave the laser in write-power-mode for more than a few seconds, even when taking a measurement. Otherwise you'll probably blow it. Start by reading the service manual for one of the Sony decks that use these same pickups. But I have no idea how you get into service mode on a TEAC; you'll have to discover that (and we will be glad if you publish those details once you have it all working). For all i know they adopted Sony's mechanisms. If so you will see that part is referred to by the common Sony name of MDM-something (mdm-7 is common in decks). The only sad part is that the IOP value for the laser probably got covered up when you installed it, so you may have (unless you photographed it) to at least partially disassemble it to read the darned thing. Quote Link to comment Share on other sites More sharing options...
Chrislisa Posted May 27, 2019 Report Share Posted May 27, 2019 Thats great, thank you - i will open it again later and try. I have a 1997 MD H500 serrvice manuel but it uses a different 210a pickup for that earlier model i guess the 260A/B is a newer laser. It also describes how to get into the service mode (plug in while holding play button then move jog dial to enter Mode) there is a LDPWR mode so i guess i need to check the number on the pick up and enter the value there - it had (0.9mw)$14 for the original ... Quote Link to comment Share on other sites More sharing options...
sfbp Posted May 27, 2019 Report Share Posted May 27, 2019 If you can identify the drive (photo would help) we can maybe figure out which Sony unit Teac used (or cloned). For a while everything came from Sony and the manufacturers would put the Sony components into their own chassis. (I am supposing, someone out there will probably have evidence telling me I'm wrong and so be it). I looked at Elektrotanya.com and unfortunately the MDH-500 is a bit older than most of the stuff they have. You'll do better searching for the manual using the full name which appears to be "MDH-500 (Reference series)". Quote Link to comment Share on other sites More sharing options...
Chrislisa Posted May 27, 2019 Report Share Posted May 27, 2019 Thank you I will look later and see if there are any numbers or markings on any of the chasis to identify it - and send pictures. - it took me ages to find that manuel but i will have another check - i saw someone else who had looked and they did not appear to have found even the one i have. Quote Link to comment Share on other sites More sharing options...
Chrislisa Posted May 27, 2019 Report Share Posted May 27, 2019 OK - i have disassembled the drive again and taken some photos (i'm really getting to like these rubber gloves !) and I know how to get into the service mode - so what to do next - i cant find any other teac manuels at the moment but as you say, i probably need to look for a sony one. I have included a picture of the original laser too so perhaps you can compare and tell me if there is a big difference between the 2. I do understand a little about electronics and i am quite good at fixing some electrical units - changing iphone screens and i have just fixed my other sony minidisc which kept trying to eject the disc even when there wasn't one inside etc.. but some of the terminology in this service manuel is difficult for me to understand and i'm not sure on the next stage ..... please look at the photos and tell me what you think ! IMG_3698.HEIC IMG_3699.HEIC IMG_3700.HEIC IMG_3701.HEIC IMG_3703.HEIC IMG_3695.HEIC IMG_3696.HEIC Quote Link to comment Share on other sites More sharing options...
Chrislisa Posted May 27, 2019 Report Share Posted May 27, 2019 This is the original pick up IMG_3704.HEIC IMG_3705.HEIC Quote Link to comment Share on other sites More sharing options...
sfbp Posted May 27, 2019 Report Share Posted May 27, 2019 Not trying to be a luddite but any chance you could post jpegs instead? Quote Link to comment Share on other sites More sharing options...
Chrislisa Posted May 28, 2019 Report Share Posted May 28, 2019 Sure, no problem - try these ..... Last 2 pictures are of the original laser.. Quote Link to comment Share on other sites More sharing options...
sfbp Posted May 28, 2019 Report Share Posted May 28, 2019 Definitely a Sony drive. Not sure which one because I haven't seen this one before but the board's (labelled N-2 prominently) style is pretty unmistakeable. But the connectors on it are CN101 and CN102, whereas on all the ones I have those two are labelled CN102 and CN103. It's running CXD-2652AR for the ATRAC chip which is the same generation as the MDS-S38 and MDS-JE510 (depending on region), I think. Those boards are MDM-3's, older than anything I have here. Hence, I think the difference in connectors, for example. Your laser iop is "0563" meaning 56.3 mA, and the one that you took out looks like a 54.8. The manual section looks lifted right out of the ones known to us and provided by Sony. And yes, it looks like you might need the LPM. Sorry about that. If you take it to someone with one be sure that the wavelength calibration is multiplied/divided by the fraction that pertains to the wavelength used by this laser (780nM) as the meter may be calibrated for some other wavelength. Mine is set on 633 (He-Ne) and so the reading must be divided by 0.73, as what the device says will be less than the actual output measured. You can try to work it out for what it should be (the IOP reading), assuming the previous one was correct and multiplying by the ratio of the 2 IOPs (old to new). But don't do the write-power part until you have the read-power working. In this case the current (and therefore the laser output) should be about 8x the read value, give or take. Study the stuff on those pages in the manual until you are really clear how it works. Quote Link to comment Share on other sites More sharing options...
Chrislisa Posted May 29, 2019 Report Share Posted May 29, 2019 Thank you for looking at my pictures - The laser was only about $14 so it may be worth trying myself but to be honest i think it is a little beyond my ability - i'm really not sure where to start. Perhaps i can take it to currys or PC world and ask if they are prepared just to do the adjusting and see how much they would charge. If it is too much perhaps then i will have a go. It is a shame really because i enjoy doing this kind of thing and apart from the time i have already spent on it i wanted to do it all myself - also whenever any one else repairs something it always seems to come back with scratches on it ! I will read the manuel and see if i can make sense of it for personnel satisfaction - Im just not sure about working out the laser power - however i do understand that you need more power to write than to read - obviously because your heating up the disc - when i have more time - perhaps at the weekend - i will look through the manuel and if there is anything i cant understand perhaps you can clarify for me - If you have any more tips on how to start that would be great ! Thank you for taking the time to talk to me it is much appreciated. Quote Link to comment Share on other sites More sharing options...
sfbp Posted May 30, 2019 Report Share Posted May 30, 2019 Not sure Currys or Dixons will have a LPM. You're likely going to need someone a bit more specialised..... Quote Link to comment Share on other sites More sharing options...
Chrislisa Posted May 31, 2019 Report Share Posted May 31, 2019 OK thank you - I shall try a more specialised shop. Is there an easy way to make sure the laser is at least working before i take it to be adjusted - just in case i have damaged it ? Quote Link to comment Share on other sites More sharing options...
sfbp Posted May 31, 2019 Report Share Posted May 31, 2019 See if you can operate the device (with a minidisc inside) with the lid off. Maybe you answered this already, that it wouldn't stay inserted...? See if it: a. spins up and runs for several seconds before either reading TOC or saying "Blank Disc" b. spins up and then immediately down again c. never starts d. spins but gives you a C13 error before proceeding further. As long as you are not in write mode, the laser power should be low enough not to fuss too much. I wouldn't try looking for the beam, put it that way. Also it would be interesting to know if the head seeks. If it doesn't you might try positioning it somewhere other than where you find it, and trying again. Quote Link to comment Share on other sites More sharing options...
kgallen Posted June 1, 2019 Report Share Posted June 1, 2019 Would you not try an Iop Write with the current setting for the new laser? Sorry I couldn't work out which picture was which. But in Service Mode you should be able to do an Iop Read, which will report what the EEPROM on the drive PCB will be holding - which will be the current for the old (original) laser that was shipped with the drive originally. Again in Service Mode, the Iop Write menu item should be used to update that value to the one for the new laser. With that done, I would be hoping the drive would at least read a non-blank disc. Kevin Quote Link to comment Share on other sites More sharing options...
Chrislisa Posted June 1, 2019 Report Share Posted June 1, 2019 OK - i have taken the cover off and the disc spins and displays 'reading' The laser does not appear to move much - I can hear it move once and then it ejects the disc after about 30 seconds. This is what the original laser did before i replaced it. ...... Hi Kevin, first picture is of new laser fitted to drive unit and last 2 pictures are of original laser If i try to perform an Iop write or read what is that called in the manuel ? Teac-MD-H500-Service-Manual.pdf Quote Link to comment Share on other sites More sharing options...
Chrislisa Posted June 1, 2019 Report Share Posted June 1, 2019 This is a manuel for 1997 md 500 - mine is circa 2000 and not all the buttons and commands are exactly the same - but i have worked out some of the ones which are different. For example to enter service mode you need to hold the 'play' button and plug in at the same time - NOT hold power button and plug in as stated in the manuel. Quote Link to comment Share on other sites More sharing options...
kgallen Posted June 1, 2019 Report Share Posted June 1, 2019 Hi Chrislisa, From that manual, it looks like there is no digital readout of the Iop setting and the adjustment in laser power is performed by tweaking a variable resistor with a screwdriver on the BD board. The relevant section of the manual is 4-1-6 Laser Power Adjustment (p9). This is a shame as to me this mandates a laser power meter measurement for each setting of LDPWR ADJUST and then adjusting RV102 which is the variable resistor on the BD board. If I read your pictures correctly, your new laser has an Iop of 53.8mA (for 7mW laser emission) and the old was slightly higher at 54.9mW. This means the current needs to be reduced to avoid burning out the laser. I think this does make it tricky for you as it seems the current needs to be reduced, but without a LPM I don't see how the adjustment could be worked out. We don't even know which way to turn RV102. If your deck is newer than the manual then maybe they've added the Iop report/set feature as under microprocessor control. You'd have to check the BD PCB to see if RV102 is there as a component. If so then you're into LPM territory. If not then it's hunting the Test Mode menus for something with Iop in the name... Regards, Kevin Quote Link to comment Share on other sites More sharing options...
sfbp Posted June 1, 2019 Report Share Posted June 1, 2019 I think the IOP is for storage of a value. It doesn't do anything per se. The newer decks allow you to tweak power by one step using the AMS knob Ultimately Iop is the current measured in the circuit. If you can set the circuit up and tweak the potentiometer until you get the iop written on the laser, that may do the trick. However be very careful when you adjust the write power. Above all do it quickly and dont look at the laser. But get the read (ie no C13 on a prooerly recorded MO disc, forget prerecorded) working first. Quote Link to comment Share on other sites More sharing options...
Chrislisa Posted June 2, 2019 Report Share Posted June 2, 2019 Thanks Kevin - I will try later - .... I take it that a new laser will not read discs if it is overpowered or underpowered - it has to be just right ? Quote Link to comment Share on other sites More sharing options...
sfbp Posted June 2, 2019 Report Share Posted June 2, 2019 Yes. And the write power not so critical except that if you have it too high you will wear out the laser unit. But you can get the Iop current to within +/- 10% of the correct value by matching that output with the value written on the laser (that you entered using writeIOP). Then you may be able to do without the LPM but the read power is more fussy. Quote Link to comment Share on other sites More sharing options...
Chrislisa Posted June 2, 2019 Report Share Posted June 2, 2019 I think the laser power is 55.8 mA not 53.8mA -or have i read it wrong ? I enclose 2 pictures of the front board and i cannot see a potentiometer on it - or do i have to remove the board to see the other side ? Quote Link to comment Share on other sites More sharing options...
Chrislisa Posted June 2, 2019 Report Share Posted June 2, 2019 Quote Link to comment Share on other sites More sharing options...
sfbp Posted June 3, 2019 Report Share Posted June 3, 2019 On 6/1/2019 at 12:58 PM, kgallen said: Hi Chrislisa, From that manual, it looks like there is no digital readout of the Iop setting and the adjustment in laser power is performed by tweaking a variable resistor with a screwdriver on the BD board. The relevant section of the manual is 4-1-6 Laser Power Adjustment (p9). This is a shame as to me this mandates a laser power meter measurement for each setting of LDPWR ADJUST and then adjusting RV102 which is the variable resistor on the BD board. If I read your pictures correctly, your new laser has an Iop of 53.8mA (for 7mW laser emission) and the old was slightly higher at 54.9mW. This means the current needs to be reduced to avoid burning out the laser. I think this does make it tricky for you as it seems the current needs to be reduced, but without a LPM I don't see how the adjustment could be worked out. We don't even know which way to turn RV102. If your deck is newer than the manual then maybe they've added the Iop report/set feature as under microprocessor control. You'd have to check the BD PCB to see if RV102 is there as a component. If so then you're into LPM territory. If not then it's hunting the Test Mode menus for something with Iop in the name... Regards, Kevin It finally hit me (I've never had to do this). If you can measure IOP then you simply adjust until IOP reaches the value on the sticker. Writing it into NVRAM is a convenience, nothing more, for service personnel so they don't have to take out the OP to read the value off the paper. I already suggested that the values are 56.3 and 54.8. Maybe I'm wrong... Speaking utterly ex-cathedra (easy to make it up when I have no way of checking my assertion), the pot must be on the component side (!) and no, you definitely shouldn''t have to remove the board from the rest as you won't be able to do the adjust. Quote Link to comment Share on other sites More sharing options...
Chrislisa Posted June 3, 2019 Report Share Posted June 3, 2019 Hi Kevin Thanks - yes i agree the new laser is 56.3 on the sticker so needs more power than the old one - and would you agree that you cannot see a potentiometer on the board - I can take more pics - and if it isnt there then the power must be adjustable with on screen menues which perhaps i can adjust bit by bit - if i can find it ... ? Quote Link to comment Share on other sites More sharing options...
kgallen Posted June 4, 2019 Report Share Posted June 4, 2019 Hi Chrislisa, Your latest photos seem to be of the display/buttons PCB rather than the minidisc drive PCB. As Stephen says, if the RV102 pot does exist then it should be in an accessible position for adjustment when the MD drive unit is in one piece and working. This is likely to be when the drive is not within a deck, but fully intact as a drive assembly. If I look back at the photos on your May 28 post, the underside shot of the drive PCB (the one showing the N-2 silk screen) then I can't immediately see an RV102... Neither can I see it on the "peeled open" photo that follows. Neither can I see an IOP measurement header. Hmmm. Kevin Quote Link to comment Share on other sites More sharing options...
Chrislisa Posted June 4, 2019 Report Share Posted June 4, 2019 OK ........... So what do you suggest ... ???? I can take more photos inside or i can take photos of the service menues or i could take it to the tip !!! Quote Link to comment Share on other sites More sharing options...
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