Bulb replacement

At http://www.movie2video.com/ the projection led was designed to fit into the old lamp fitting, so the original adjustment can be used for the new led. This seems like a good idea. At movie2video the lamp was connected with two wires, but the lamp fitting is more complex for my projector.

 

To fabricate the led lamp first I broke and removed the glass from an original bulb, to leave only the bulbs metal fitting. Then I cut some sheet aluminum to fit into the original fitting, this was shaped to fit inside the projector's bulb compartment. The aluminum sheet also acts as a heat sink for the led. The new led bulb fits in the projector, but still needs a little fine tuning to ensure the led fully illuminates the frame.

Stripboards

This weekend I have finished the main boards for the projector. On the left is the board for the white led that will be used as the light source for the projector. It includes a FET for switching the led power, and a set of resistors to limit the current. These make up a cheap potentiometer,  the red wire (not attached in the picture) can be connected to one of the resistors with crocodile clip giving a range from 1 ohm to 30 ohms.

On the right is the motor and gap detector board. The motor runs from it's own 12V power supply, and again a FET is used to switch the power. Something is wrong with this board, as the motor runs on it's own if only 12V is connected and the FET can get hot. To be investigated further ...

It's christmas!

So christmas did come early, very early in fact. My Ardunio and assorted components arrived at 8:30am yesterday morning, that was speedy deliver. The circlip pliers turned up a little later too, but it turns out they are slightly too big - will have to try to find some different ones.

Last night I assembled the Ardunio proto shield and finished the night with a working button and fading led. Just two small problems, you can't upload to the Ardunio Uno using OSX 10.4.11. Yes, I know that's very old and I should upgrade!. Once I figured out that was the problem I switched to a Windows 7 box for writing the sketch (aka as a program :)) and it all worked fine. I also messed up the wiring of the switch, and didn't include a pull up resistor. This meant the input was floating and the input was random. Not a problem, as you can enable an internal pull up in the software. Once I figured that out it worked a treat.

Tonight I have assembled the gap detector in a small strip board. It works too! This will be used to detect when a frame is ready to be captured by the camera. For testing now it makes the little red led turn on briefly.

Next up the BIG WHITE LED!

Shopping

As well as starting this blog today I've been shopping online for components, on it's way are:

• an Ardunio and proto shield
• Luxeon white led
• DC motor
• resistors, capacitors, diodes and fets

Everything apart from the motor is in stock, which will ship in three days. The site says delivery is next day for stocked products, but does that mean my whole order will be delayed? Or will Christmas come tomorrow!

This should be most of the parts I need but I still need to work out the how to connect the DC motor to the drive shaft, the diffuser and the optics.

Electronics

The modifications will include adding an LED light source, frame generator and motor control. I am not good with electronics, so when I asked my friend Caleb about the design at http://www.movie2video.com/ he said that's the hard way, and instead I should use an Ardunio for the control. That moves much of the work to software, and I'm good at that :-).

These are my working schematics, donated by Caleb. Thanks!

Demolition

This is what the projector looks like before I started the demolition. The main parts to remove are the transformer, motor and main circuit board. After disconnecting the main wiring these are easy tasks to start with.

 

The shutter mechanism can be seen on the left. I will need to modify the shutter and removing the 40 year old grease and re-lubricating should make it run a little more smoothly.

I was defeated by the circlip's holding on the gears. Circlip pliers now ordered, this will be a job for next weekend.

And here we have the main drive shaft. The original motor used to drive the rubber disks, this allowed 18fps and 24fps to be selected mechanically.

After stripping down the drive shaft here are the parts. Removing the rubber drive wheel was hard, the two grubs screws were stuck hard. I actually bent the screwdriver tip, ouch. Finally pouring boiling water to heat the parts made the difference!

The Donor

I have my Dad's original Dual 8 projector (that can play both Standard 8 and Super 8), but I don't want to do a hatchet job on that. So first step is a donor projector. It's amazing how popular cinefile projectors are on ebay, especially Eumig projectors. After a few projectors went over budget I finally won an action for an Eumig Mark S 712 D dual 8 projector. This projector includes sound, which I don't need but it won't harm.

 

Next job is to strip it down.