jim.hoggarth

Just let me know if the cottage next door comes up for rent !!!

Hi. On the JB940, sounds like there could be two problems. Is there a disc actually stuck in the drive? This model uses a variant of the MDM-7 drive, and one of the common problems is bad eject caused by a slipping drive band. It's the only rubber drive band in the unit, and easy enough to swap once you know how to remove the upper slot mechanism. If you can manually help the disc to eject, it may spring back into life. Sometimes just by touching the top of the jammed in disc with a finger or tool is enough to give the drive band a jog to help eject the disc. If you manage to eject it, and reinserting brings you an error (usually C13 error), then chances are the spindle motor is also goosed, or maybe but less likely the optical pickup. When a disc is inserted the mechanism first tries to focus to determine if a disc is inserted, then spins up the spindle motor to read the TOC. If either of these fails then a C13 error is shown. Jim

Almost definitely the overwrite head. Although the same head is used in many different models, the N707 (and N1, and R700) seem particularly prone to this. Still, an easy fix. Are you in the UK? If so I can do the repair for you quickly and at reasonable cost. Even if you are out of the UK it could still be worth your while getting it repaired. But certainly see about getting a refund from the seller first, especially if they claimed it was a working machine in the auction listing. Jim

Stephen - the ABCD and EF stuff. I assume you mean the A-F signals coming from the laser unit? All optical disc lasers need ABCD in order to focus on the data. An algorithm such like A-C + B-D generates an error signal for the focus coil. The theory is that any slight change in focus causes an imbalance in the signal received by these four photo-diodes and can be used to keep the laser's target lens in focus with the track despite any up/down movement of the disc relative to the sled carrying the optical pickup. The E and F photo-diodes are used to generate a lateral error signal for perfect tracking. These diodes are not associated with the data stream, a separate set of photo-diodes read this, I and J. I understand there are other systems which use two I and J diode pairs for both signal and tracking too. Plus, you can also find another photo-diode used as a control for the laser output, to stabilise the light output from that. Phew! I am sure there are some errors in all that BS I have just typed, so apologies now. Incidentally, when you get faults on the optical pickup it is often these photo-diodes that have failed, rather than the focus or tracking coils, or indeed the laser itself. Jim

I have a gut feeling here that it's the famous IC302 problem - the headphone amplifier IC. Probably needs resoldering. Not much more advice I can give, other than post them off to me and I can fix them for you. Parts not a problem if required. Decent price for regular customers! Jim

Hi Sergio I don't have anything to trade, but I just wanted to ask - do you mean the R90 silver? I believe the R91 was only made in Blue, White and Red. Jim

Very strange and uncommon type of fault. Normally sounds just cut out completely, either due to a bad connection or a problem with the optics/alignment. Reduction in signal implies an analogue fault, but of course there is very few analogue signal paths in an MD recorder. But then, I have come across some really weird problems before now. One thought - could it be that the audio drops low and with a strange, ethereal far-away effect, and do vocals almost disappear? That would indicate a bad earth connection on the earphone output. And the fact you have an N505 with the same symptoms leads me to think it may be bad joints or solder pads on the output chip. However, that would also affect all discs, even those recorded on another machine. Jim

Hi. Can you expand on the drop-outs? Do you mean recording carries on, but the volume drops, or does recording and/or playback randomly stop and restart with blank spaces? Most parts are readily available, by the way. The S1 uses many of the same components as the N505 or N510, if I remember correctly. Jim

Ha! A neighbour of mine, whom I detest incidentally, calls me Jimmy Savile because of my long almost-white hair! Jim

This is the cheap portable they brought out using the same chassis, motors and chipset as the N510. Sound is fine, usual Sony quality. The build quality is the same as the N510, N520 and the rest of that era. I personally dislike them as the display is so small, it only shows a few characters and you seem to wait ages for the track titles to scroll by. If the Aiwa is genuinely 'as new' it could be a relatively good purchase, certainly if you could get it cheaper, but I doubt it is new as the charger is wrong, and it is a Panasonic battery. Aiwa gumsticks are mainly silver with an orange strip at one end, if I remember correctly. Blatant sales plug: I have plenty of players in stock, mostly Sony of course. If anything takes your fancy while you peruse the market, just shout. Jim Forgot to mention - the Sony E310 has no remote control socket either, and only takes AA dry batteries, no charger socket. Jim

The battery is actually pictured. It is black with green lettering - pretty sure this is a Panasonic Nickel Cadmium battery. Probably on its last legs. Jim

It takes a standard gumstick battery. That is not the original battery charger, by the way (unless Aiwa shipped some boxes with a different charger - Sony did this once supplying the MW305 instead of the AC-ES305). I don't know if that makes the package look like less of a bargain, personally I think it is a bit expensive. And if the charger is non-original, what other bits are not 'mint'? Jim

Aw, shucks! You're making me blush now. Jim

Hi. I have plenty of these in stock. I assume the plastic door and its smaller plastic hinge part is still with you and in good condition, and all you want is the plastic and metal contact block? If you don't get any joy in the US, send me a PM and I will make arrangements with you. Jim

What! I know the folks who work in these shops aren't that bright, but fifteen quid for a Sony MD deck of any type? I used to frequent these shops regularly when I was a public transport user (no parking in front of most of them due to their city locations), but all I ever saw was tat in the audio section - usually just DJ gear. And lots of guitars, amps and pedals, of course. And videos/DVDs that had been so badly abused you wondered if there's a factory somewhere that makes pre-scratched CDs and DVDs inside pre-torn cases. Jim

Hi Nick. Yes, usually. I have a recorder in for repair now with one of these gumsticks 'in the slot'. The top of the green outer has been cut away at the positive end, and replaced with thin insulating tape. Obviously a common problem, as I have heard of this before. The excess of plastic can prevent the contact strip making with the top of the battery - the contact comes from the side, across the thin edge and onto the contact 'pip', rather than coming at the battery from 'above' the contact, if you see what I mean. Must be very frustrating for users with no mechanical bent as they will just assume the batteries are crap and complain to the seller. And that could be another MD user lost to the iPoo. I have never used these batteries myself, always prefering the Pisen brand from HK. Jim

Have you had the machine apart at all? If you have disconnected the display board, that's exactly what you get. The reset button doesn't really 'click' like a normal button, but it does push down very slightly, say 0.2mm? Thanks to Stephen I now have the AM-F80 service manual. I can confirm that NO ADJ is caused by the service adjustments not being completed, and presumably by a corrupt EEPROM too. I notice there is a main EEPROM and a secondary memory with battery backup. I assume that is for user settings such as the last track played, bass boost and so on. I doubt the EEPROM would lose it's programmed state with not being used for several years, but I suppose it is possible. You will need to run the adjustment routines. To be honest, I doubt you will be able to does this yourself as special tools are needed and a basic grounding on how minidisc recorders work, such as stuff like 'servo engaged', 'OWH loaded', high reflectivity and so on. We could be here until Christmas going through the procedures when I can do it in half an hour. Do you want to send the unit to me and I can repair, service and realign the unit? For a small fee, of course, as it is my line of business! Jim

Unfortunately the free links are just for technical bulletins or the parts lists. I need the full service manual, and I would prefer not to have to pay for something I doubt I will ever need in the workshop. I was hoping to find instructions on entering service mode on-line, but it seems nobody is really interested in the Aiwa MDs. I will continue looking. Jim

Fact is, it's not what you are looking for. The F90 is just a Sony R900 with cosmetic differences. Even the remote control is a Sony RM-MC11EL, with the lettering changed on the front. Incidentally, I had a revelation a couple of days ago regarding the NO ADJ error. I am wondering whether it is equivalent to Sony's NVERR or Error EE messages. In other words, the non-volatile EEPROM has become corrupted, effectively turning your recorder into a box of parts. The solution is to run the internal adjustment routines, but without a service manual or some hints as to how to enter service mode, there's no way of fixing this. I am very busy at present, but hopefully I will have time to pull out all the Aiwa machines and check this out. Jim

Yes, I have seen that too on eBay. Sorry to disappoint, but inside it is a Sony R900. Jim

Good news - I have located my box of Aiwas and run through the machines. Most of them do not work, giving Caution! errors or just plain dead. Luckily one AM-F75 seems to work ok despite having a damaged jog dial. I have also found four Aiwa batteries, and have one on charge now. All I can do is charge each battery up fully, and play back prerecorded discs on shuffle repeat, to see how long the batteries last, A few cycles should give me a good idea of each one's capacity. I will let you know if any have a half-decent charge capacity in a few days time. Jim

Your dead right Stephen - check out paragraph three here: http://www.cdmasteringservices.com/dynamicrange.htm Jim

Thanks for the photos. It's not the drive I thought it might be, sorry. The overwrite head looks very Sony, so it's possible the laser unit is a Sony one too - probably the same optical pickup as the JE510, S39, JE320 etc. But the rest of the drive is possibly pure Denon. The fault does sound like bad switch contacts. These drives usually have up to four switches that feed back positional information to the drive processor. States such as disc-in detect, disc loaded, write head engaged. When the processor initiates an action, such as ejecting a disc, and the switches don't send back the expected info after an expected time, the drive will shut off and display a 'mechanical error' message. Grundig's are famous for it. Often all the switches are mounted on a single board. If you can locate a plastic cam gear driven by the disc load/eject motor, the board should be above/below this. Giving the switches a quick squirt of switch contact cleaner may do wonders. Just be careful you don't spray greasy crud all over the drive unit. If in doubt, get an engineer with some experience of this type of gear, such a VCR technician, to look at it for you. Alternatively you could pull the drive out and post it to me. I am sure I have two DMD1000's in storage somewhere, both with faults but I can't recall what. Perhaps it's time I learned how to strip them down! I am in the UK, give me a PM. It is the DMD1000 isn't it? Jim

I have a few of these batteries, I am sure. What state they are in I don't know. I remember selling a couple of decent working ones to a guy two years or so back, but whether I have any good batteries left I am unsure. I don't do much with these recorders anyway, most of them come up with the dreaded 'NO ADJ' error I haven't been bothered finding out what causes it. At least not yet. I was toying with the idea of getting rid of all my early Aiwa stock anyway, or I may just keep it in case parts are needed in the future. Perhaps if the service manuals for Aiwas were readily available I would have more time for them, models such as the F65, F75, F80 etc. They are actually very nice machines - they remind me a lot of the Sony R55, which I do like very much. If you haven't found a suitable battery yet, give me a shout and I will dig out the Aiwa box from storage. Jim

I regularly see ads, usually on eBay UK, which include misleading or just downright wrong information, or a listing for a recorder with wholly incompatible accessories. One of the most recent was an R-series recorder (R500 or R410 I think), with an RM-MZ1T radio remote and a NetMD style USB cable! I used to message these folk to point out their mistakes, and the fact they were opening themselves up to the prospect of negative feedback, but nine times out of ten I got no reply or the reply would be short and rude. So now I just watch the item, then check back a few weeks later to read the bad feedback! Aren't I naughty. Jim