EngTech

Hi Dave, I've had a few of these gearboxes apart, and every gearbox has different broken or shredded gears. Ultimately it's a very poor design and not robust enough. The gears are injection moulded I'm not sure what material, I very much doubt that a 3D printer would be able to produce a gear that even comes close to handling the torque required as ultimately they need be substantially stronger than the originals. To be honest the the gearboxes are so bad I wouldn't waste time with them. I've managed to bypass a couple of the gearboxes by fitting a small PCB that I made, it means you have to open the mirror by hand but the projectors now work fine.

I've got quite a few, including :- Multiple Amigas including an A4000/40 A few SUN unix boxes (Sun Ultra X86 and Sun Ultra Sparc) A few SUN/Cobalt RAQs, An almost mint condition SGI Inidigo. Plus the usual pc's and macs. This is my SGI box... you just have to love SGI's

I've managed to have a very quick look at the plausibility of the LED hack, the Kingbright 12V LED would not cause an issue when running the correct polarity, however this is where my concerns were originally aroused as the motor driver BA6287F reverses its polarity to close the mirror, and also to confirm the mirror position. So in effect we would then be putting reverse ≤12v through the diode, Kingbrights datasheet states an absolute maximum reverse voltage of 5v. This would suggest that even if the hack works it is a risky way to go as the LED will eventually break down and cook itself, possibly causing damage to the BA6287F motor driver.

I guess the important thing to know is are all the images in one directory or are they spread accross the server in different locations? Ultimately if you need to convert 1.6 mil photos you need a script that can automatically traverse the directory structure and convert on the fly, otherwise you'll need to manually select all the image locations which will be a job in itself. I've recently written a similar script for a clients web based gallery using PHP and GD, it was fully automated and converted the images on the fly. Personally I'd be tempted to write a similar script to iterate the directories then use imagemagick to do the conversion. (https://www.imagemagick.org). It would be pretty simple to do under Linux, marginally more frustrating under windows.

I think it's difficult to recommend one as there are simply 1000s out there many of which are identical but branded differently. Importantly how long is your cable run going to be? For example if you hooking up a projector on a long cable run, could you use an A/D converter at source? e.g. S-VIDEO to HDMI as digital will carry the signal over a distance with less picture degradation than a long analogue cable. If your talking about only a short run i.e. VCR to VCR 🤔, then I doubt you'll notice a huge difference in any cable.

If I get some time later on this evening I'll drag one of the projectors out have a closer look at the schematics and have a probe around with my Fluke, simply dropping a diode across a 12v output doesn't sound like a great idea and may even damage the (BA6287F) motor driver. If I get time I'll make some small PCBs that can simply plug in and bypass the motor and logic circuit completely, so put an end to those pesky gearbox problems!

Having just read this thread and coming from an electrical / electronic engineering background, I'm a little sceptical and quite concerned regarding the suggestion of wiring an LED across the output terminals of the motor. Firstly I've not tried this so can not say if I actually works or not however an LED being a diode basically has the following electrical characteristics:- Forward current flows as normal I.e. a direct short (slight volt drop but negligible) Reverse current blocked I.e open circuit (if the diode is overloaded it will simply fail and short circuit) So I can only assume the LED that is being suggested has an in built resistor to suit the 12v output. As far as I can tell from the schematics this projector (as with most consumer electronics) monitors the current of the output terminals infact the service manual states there are "over current" settings in the "factory" menu. But I don't see how this LED could trick the mirror motor logic, and position circuits. As I've said I have not tried this hack, but the only conceivable logic behind it that I can think of is if the mirror motor endpoint switch (photographed by gkkes) is actually only used to check the mirror posistion then the current monitoring could possibly be used to confirm the motor has reached its hard endpoint I.e can't turn any more (large current increase). I would be really interested to hear from any user who has tried this hack as I have a few of these projectors all of which work apart from the mirror.

Hi All, this is my first post Sorry for pulling up such an old thread, I also have one of these projectors and would like to know if (and how) it is possible to reset this warning without knowing the pin. As I understand it the warning is a security feature to prevent theft. From reading the docs the orginal owner can set a PIN number for the projector, this pin number needs to be entered in order to override the warning message. However if the owner forgets their PIN a ten digit "Inquiring Code" can be displayed by holding "RESET" for 3 seconds. The displayed "Inquiring code" can then be sent to an Hitachi dealer who will upon confirming the owners details provide the correct PIN code. So does anyone know if this can be reset maybe via hardware, firmware update, etc etc?