And so begins the PLOG!

Well, construction is probably a few weeks away, but for now a kind of shopping list and some initial thoughts and comments. Thanks to a few members (you know who you are) for initial hints and tips Looking forward to getting going properly...

My build will be based aroun the popular and well documented (thanks HAAS man and others) HAAS-style curvy case. I hope to get everthing inside the one box, but time will tell... Here's a quick something I knocked up in AUTOCAD based on the standard dimensions

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The case

The shell will be constructed from 18mm pine furniture board from B&Q, held together with M6 furniture bolts from www.screwfix.com. The top and bottom will be from 4mm ply, with internal 18mm dowels and heat shields, probably aluminium sheet. Did I mention my employer has a woodwork shop ?

The optics

Standard 15in frensels and projection triplet from lumenlab.com

Shower drain (for focusing) from Home Depot (thanks mystery shopper!) I don’t think we have anything remotely like this in the UK! These are now made in black, which is a bonus (most pictures in the forums show white PVC)

The telly

The projector will be based around a Relisys RLT1520 LCD panel. This is sold both as just a computer monitor, or as a slightly fancier version featuring a module that add adds television and video capabilities. So not only is mine a good looking 1024*768 panel (for the moment anyway) but features the following inputs:

- VGA 15 pin DSUB
- Composite video
- S-video
- Component video
- Aerial for inbuilt tuner (PAL/SECAM/NTSC)

And there’s a bonus remote control too!

I don’t know how strippable this model is Another individual on the forums has one, but liked it so much they never took it apart! I can see where they’re coming from…

The lamp and reflector

I’m probably looking to buy a MT400SX from Eye Lighting Europe, with additional hardware (ballast, ignitor and capacitor) from www.lampig.com. This lamp, once in the holder, will be a little too wide for the standard enclosure dimensions, which would require the centre of the lamp to be at 7” from the base. So I am considering either going a little wider on the case, or recessing the lampholder into the side, with a mounting plate on the outside of the projector.

If anyone has any suggestions for UK sources of shorter MH lamps I’d welcome them

E40 lamp base purchased on eBay (suitable for UK lamps)

I have both the Blanda Blank bowl and Soaré napkin holder from IKEA, just in case. Note that the Soaré range is being discontinued, and not all of the IKEA stores had these in stock (as of a few days ago), so I got a couple in just to be safe! My hunch is I'll probably go with the napkin holder since they seem more spherical (no flat bottom) and a little shinier than the bowls.

Cooling

240v 120mm fan from Maplin electronics. I’m hoping to get away with just the one fan and some careful design, however will leave space for an additional second fan if it is needed.

Future plans

Once (and if ) I get the basic projector up and running, future plans are:

- Modify the electronics so the remote control switches the entire projector on and off, i.e. also controls the lighting and cooling fan

- Add a time delay circuit to keep the cooling fan running once the bulb has been switched off

- Add audio output to the projector’s built in tuner, at line level. There is no headphone jack, the only audio is via the built in speakers. Yes I can always use an external tuner, so this is just a 'nice to have'!

OK I had a quick peek inside the back of the LCD! Here's what I found:
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This is as far as I got for now. The screen is connected to the board by a couple of flat connectors - here's a close up:
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I have bolted the thing back together for now, but would welcome some advice on these. My guess is the tape is just there as a security device and that it can be peeled off. Should it then be possible to remove these cables from the connectors? The larger of these is 45 (possibly 46) tracks, so no extension is available for this if I end up needing one. I don't know what happens between the other ends of these cables and the panel itself yet

She's back together as intended for now and still works

That tape is designed to prevent shorts and to be easily removed. You should have no problem removing that tape.



Yes, each connector has two tabs at both ends. The tabs will either pull straight up, thus loosing the connector, or they hing up allowing the cable to be removed. In either case, those tabs are not designed to be robust, so just take your time and you should have no problems.
They require very little force to disengage, so be nice.

OK I have a plan on the lighting front now!

Just found the 400W double ended MH lamp and accessories available on the French site www.izzotek.com and mentioned a few times in the forums (search for 'Radium'). This seems well specced for the job and will fit my 14" (imaginary) wide case nicely. I did the maths and it works out about the same ordering the other lighting hardware from these guys too. They do a complete kit which curently works about £78 inclusive of insured postage, so that's fairly comparable to what the lamp and all the bits would cost me on home ground.

BTW the guys at both iwasaki and lampig were really helpful on the 'phone, and come recommended if you have a larger case and can fit the longer bulbs.

Anyway I have one of these chaps on order now

Hurrah Lamps arrived today, all the way from France. That's about 10 days from placing the order, which isn't so bad. Anyhows, here's what you get in the lighting kit:
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There's some subtle difference between the two lamp ends (different order code), but I haven't figured what it is yet, other than a slightly different style of mounting bolts [edit: I asked the French, the difference is the bolts, that's all!]. So in this pic is the lamp, capacitor, igntor, lampholders and ballast. The whole shooting match weighs a fair bit, so my machine is going to be a hefty beast when she's done.

Lacking any progress on the projector case (day job :angry:) I simply had to try this chap out so built myself a test rig:
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The distance between the two sets of bolts holding the lampholders is 200mm, which leaves the lugs the lamp sits in at 180mm apart. There's a little adjustment on the bolts, so no need to be that precise.

So I flicked the switch from a safe distance
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But about 1 second later was plunged back into darkness.
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Seems I had been a little over-cautious with a 3A fuse which is equivalent to 720W power. My guess is the bulb, rated 400W, draws a little more power when springing into life? We're now running with a 5A fuse, and:
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Get those sunnies on - this thing is BRIGHT!

BTW for any non-UK residents out there, our plugs have fuses built in, which is why you won't find it in my rather Heath-Robinson-esque rig photo. The finished projector will however have its own built-in fuseholder.


Initial impressions are good. The lamp started up through a blue phase, then green, then finally settling on what appeared to be very pure white. Best of all, being smaller than both the OSRAM and IWASAKI bulbs it will fit in my non-existant box! (though I have bought the wood....). Plus I didn't catch any noticeable buzzing from the gear i.e. the cooling fan will be louder!

So next step is making a start on the woodwork...

A couple of questions in the meantime:

1. Are there any dangers handling the capacitor post-use, i.e. when I disconnect it, will it still be charged?

edit: found a thread on this one. Seems capacitor should discharge itself through the ballast when powered down, and there is a resistor for that purpose. Still a quick check with the 'ol voltmeter would be a wise precaution before touching it...

2. The packaging mentions a 45 degree mounting safety zone for the lamp. Am I correct in thinking this relates to rotating about a single end (i.e. that axis) rather than rotating the lamp through an axis running end to end? i.e. it doesn't matter whether my lampholders are pointing towards the front of my case, or the top/bottom. Hope that one makes sense...

Be very carefull with that capacitor. It's a very good idea to check the voltage before touching it. Even if it's been disconnected for a long time . Good capacitors can keep their charge for a very long time. You can discharge it using a resistor but be sure that the resistor is high enough (so it discharges slowly) and that it can sustain the power. If not sure, don't do it.

When in doubt, don't touch it !!

Thanks for the advice. As you rightly say, the easy thing to do is to check it with the 'ol voltmeter before handling

OK here we go with the build! This was made possible by a rainy saturday to stop me playing with model planes , and a router loaned from work . I have been really pleased with the results so far - it's really isn't hard to get things fairly accurate using this method.

So here we go... I'm going to go into lots of detail here, so hopefully you guys will find it useful - and as a disclaimer, I'm assuming everything will fit inside based on the 'standard' dimensions - don't blame me if it doesn't! Time will tell...

The case is constructed from 18mm pine furniture board, which has a nice finish. You could of course use MDF, plywood etc. I got me a couple of large panels for the sides, and a long strip which I will make both the front and back from.

First step is to mark everything out. The really important thing to get right is the positioning of the four holes that will hold the dowels. In mine, they were 225mm each side of the centre line horizontally and 90mm vertically. Drill your four holes large enough to hold some small screws for now. Be as accurate with these as you can - ideally use a drill press if you have access to one. I also marked on both panels all the important verticals, such as the front and back, and lines to show where the router needs to go - oh and the LCD and lens positions of course!

I built myself a trammel to go with the router, which is essentially like a big compass cutter. In metric, the outer radius of the case is 1175mm, with the inside edge of the outer groove at 1164mm, and the inside edge of the heatshileld grooves at 1146mm. There is one more important dimension: if you do the math, the fixing screws work out at a radius of 1135mm from the same imaginary origin. So what use is that? Well...

Use the trammel to mark out a curve on your workboard (say 0.5mm deep cut) at the 1135mm radius. This, and all router cuts I made, use a 5mm cutter. Something like this:
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Next pick a couple of points on the inside of the curve which are 450mm apart (the horizontal distance between the support dowels), and drill a couple of small pilot holes. The arrows in the picture point to these, honest! Then, screw the panel to the board using these holes to hold it firmly in place. The holes are M3 to match the screws and countersunk for now to keep the heads out of the way of the router trammel. Longer term they will be recessed to 19mm diameter to match my dowels.

The trammel has four positions, for the four different arcs I am using. So one down, three to go...
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I moved the trammel to the largest radius (1175mm) and marked the edge curves on both boards. These were about 2mm deep for now, to be kind to the router
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Next, I set the cutter depth to 7mm (seemed like a good number) and cut the top/bottom rails and the heatshield holders. These are at a radius of 1164mm and 1146mm respectively. Watch out for the rails, since these stop short of the front, but go all the way to the back.
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And voila, there's all the curves cut. I still need to cut the groove for the rear heat shiled, and finish the top/bottom curved edges.
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You might have spotted this, which is my attempt at an adjustable lampholder. My lamp will be held both sides, being double-ended, so this allows the lamp to be adjusted forwards and backwards by about 20mm each way from the assumed 'correct' position, which is 220mm from the rear frensel. A bolt will hold this to the side panel, which can be loosened to allow it to be moved. These brackets are from B&Q. So I routed a slot each side, the same height as the bracket and 20mm wider each side based on the central position. The depth is about 2mm, roughly the same bracket thickness.
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The final step was to trim the panels to length - you could use a mitre saw, a table saw, or as I did, the router and a batten guide.

Next up, using the curve I made with the router as a guide, I used a jigsaw to cut the sides off, a few mm oversize for now
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Then it's back to the trammel to clean up the edges
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Another shot of the router in action...
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Now for the front and back. The first step was to cut the grooves for the top and bottom panels. I measured the distance between the grooves on the sides at the point where the front and back are attached, and matched this position (I think it was 190mm). Using a router edge fence I cut the two grooves, again 7mm deep, then marked up for the other components. For now I am making a single length, but this will be cut into the two 14" (356mm) pieces . So here's ths grooves, and the markings for the lens and fan.
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I've included space for a second fan if I end up needing one, but for now am going to try and get away with just the one. I'm also cutting a rebate which will hold the power inlet, fuseholder and mains switch, all mounted on a sheet of aluminium.

Next up I cut the circles using the rounter and a larger circle template I cut out on a fretsaw. In hindsight, I should have used the trammel again (although somewhat shorter) to make the template, which would have been much more accurate. Anyways, here's the lensholder being cut - it should be fairly self exaplantory how this works, just a bit of maths. I've also cut a rebate using a slightly larger circle as a guide.
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I used a larger circle template to cut the fan outlet, and wooden batten guides to give me straight lines for the panel cutout. On the back of the panel I have cut rebates with the router freehand - these won't win any prizes for neatness, but not to worry because they'll be hidden inside the projector.
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Test fitting the fan:
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And the lens:
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So all's good for now. Next steps are to get the thing bolted together with the dowels in place, then maybe round the edges with some fancy router cutters.

Now I've got all my parts cut, has anyone got any tips on the best assembly sequence to get the things square? I have drilled the holes in the sides with a drill press, but still need to drill the support dowels and front/back panels. I was thinking it would be best to do them in situ.

Cheers

OK lots of progress on the box today, largely made possible by use of company facilities (mostly out of office hours of course

All fixing are held by M6 furniture bolts and metal threaded inserts, meaning that the machine can be taken apart countless times in the future without worry of the threads wearing out. The heads have a hex key fitting, and look good on the outside. I think these are similar to what HAAS_man used in the original design.
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I - sorry WE - first bolted the front and back panel to the sides (thanks mystery helper) which seemed to go together nice and squarely. The four supporting dowels were then bolted into the 18mm holes I had recessed into the side panels today. These were about 7mm deep, so the total dowel length is the width of the case (14") + 14mm.

So all's looking good for now. Here's the machine without the top and bottom panels:
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And yes one of the panels IS the wrong way round oops...

The upper and lower panels are made from some bendy ply we have in the warehouse (thanks work ) - no idea exactly what the spec is but it is 4mm and floppy as hell in one direction so ideal for this.
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Installing the fan - because I can!
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The back panel is not my greatest piece of work, but I guess I can replace it in the future! That's the beauty of the homemade projector!...

I should also add that the machine is really quite large! Though I appreaciate it has been designed as small as it can be. I guess because on the forums you don't see people next to them (and I'm no exception...) it's hard to judge the scale! It fits in my car and that's all that matters.

Next steps are to sort out the edges properly, varnish the entire enclosure then get going in the innards. I need to source some metal sheet (probably aluminium?) from somewhere for both the heat shields and the rear control panel. Not quite sure where all the AV inputs are going to go, but I might add another recessed panel in the RHS near the front.

you might want to cover the rear dowels to keep them from getting cooked by the bulb. I use hollow chrome metal tubes made from shower curtain rods, just cut them to length and slip them over the dowels. nice looking box btw.

Thanks - I had that in mind. I think I might have some knocking around somewhere...

This weekend is looking rainy so might be time for some more routing

Very nice woodworking, Richster!

OK I have been at the router again =safety goggles. I went round all the side with a rounding bit, ending up something like this:
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I also angled the front and back panels using a circular saw so that they line up with the edges of the case.

Next up on the list is the lampholder. Here's my creation for now:
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This will hold the two lampholders at the correct distance apart (200mm) while I get the machine up and running. Once I get the optimum position for the lamp figured, I will slice out the central section and put the relector in position. I think I might also have to put some heat shileding over the two side pieces, or I may have made myself a large fire risk? Any thoughts on this? When I ran the bulb in the test rig, the central position directly under the arc got a little scorched.

Essentially this is nothing more than a strip of wood, cut to fractionally under the width of the case. I routed a channel on the back, to fit the brackets tightly into:
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OMG - I think I am becoming a router addict. Good power tool!

A couple of screws attach each bracket to the wood, though I have ground these down with a gridstone so they are flush with the panel and don't intefere with the lampholders.

The two lampholders are bolted 200mm apart from the central point.
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My other reason for leaving the two sides attached for now is to reduce the risk of accidental damage to the bulb while setting up and testing, given that each end of the bulb can be moved independently.

Today I coverered the rear dowels with aluminium tube. This was knocking around in the garage - the size is nearly perfect Also take note of working in daylight hours for a change
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The lampholder is fitting nicely - it just needs a screw in each side to lock it in place once I have found the optimum lamp position.

Today the back panel is missing, because I am making a new one. I was unhappy with my routing efforts on the original so made myself do it again, properly!

Also I had another thought on ballast positioning. I think this will work well, though it will mean adapting the rear heat shield panel when I have this (you can see it straddles this line) and building some additional shielding around the ballast. In these pictures the lamp is in its rear-most position, so this is a 'worst case' scenario. Moving the lamp forwards will give a little more clearance. There will be a bit of air movement here too which is a bonus, unlike the front of the case. The photos are of the bottom RH corner, looking at the unit from the back. My only issue will be if I end up needing a second cooling fan then the ballast will have to go the front of the case So let's hope I don't...

From the back...
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And from the front...
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Looking good, I would cover the wood on the light holding bracket with something, maybe just thin aluminium?

Dont know if you said but how do you plan on mounting the reflector?

I wish I had got a router for my projector, would have made it alot easier

Thanks Nick

I agree totally, though I have yet to get hold of aluminum. The central section of the mounting bracket will be chopped out as I mentioned, though thinking about it I might be able to mount the relector to this somehow, so it moves backwards and forwards with the lamp. I currently have the choice between the BLANDA bowl and the SOARÉ napkin holder (last two in the country, well nearly!) - I'm open to suggestions!

I was looking at routers at B&Q - they do them for about £100 but don't know if they're any good. The orange one I have on loan from work retails at about £250, but it's a very nice bit of kit. Every man should have one

edit: does anyone have the focal length postion for the SOARE napikin holder to hand? I'm sure it's in the forums somewhere, but I haven't spotted it recently. What I'd like is the distance from the centre of the bulb to the rear of the bowl. Or I guess if I knew the radius of the hypothetical sphere, I could work from that. I presume the BLANDA BLANK is close enough hemispherical, so no problems there.

I picked my aluminium up off ebay for £15 inc delivery for 5 sheets of 1m x 75cm which was perfect for flashing the projector (not in my plog yet)

After seeing your plog I decided I will buy a router and well its only a cheap one for £30 but it will do the job i hope But because I already have cut my panels I will have to do it by hand I think

Also where did you get that shower drain thing

rich..... that wood for fc2 lamp mounts is gonna burn,,, its way too close to the lamp

It's from the USA I'm afraid (home depot I think) I have my contacts sorry HAD my contacts, they're back in the UK now I think like many things in the USA it's a bit bigger than anything we have here. Mmmm bring on the diners! Also nice they are making them in black now (though the cover grille which you'd see in the shower is still white)

Re the routing - if you have been generous enough with your chopping, you might be able to use the router to clean up the edges maybe?

How thick was the ally? I think I want some thin-ish sheet for the heatshields, then some thick material for the control and connector panels (the connector panel doesn't exist yet, but will probably be front RHS - looking from the back that is!)

As I wrote, it's going to be chopped out - just for alignment purposes at the moment...

My aluminium was thinner than a mm, could be bent to shape easily, cutting was no problem at all, its perfect for covering wood as its not too heavy either

sorry, thats what happens when one reads only part of a story,,

This evening I have made a start on the wiring, with a view to getting the lamp up and running in the projector. First step was to make a control panel out of aluminium sheet, and mount this into the cutout. Note this is a replacement back panel, since some of my routing was a bit suspect on my first attempt . For now I have mounted an IEC mains inlet, 20mm fuseholder and DPDT switch into the panel. I also got myself some special metal-cutting jigsaw blades, which make cutting the aluminium a breeze and I found it was possible to be fairly accurate.
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So that leaves a space at the top…. I reckon the video inputs will all go towards the front of the machine on a separate panel (a safe distance from the 230v too), but was possibly looking at a temperature module for this location or maybe some indicator lights.

How about one of these? This runs off 1.5V - I could get that from my screen PSU with a little circuitry

Anyway, it’s room for new features in the future!

Now to the wiring…
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All LIVE wires are brown, and NEUTRAL are blue, as per UK wiring specs. The live and neutral from the mains inlet both go to the switch, the live via the fuseholder. I’ve then taken a branch off this to my connection block, so for now my fan is always on when the mains is plugged up. The outputs from the switch go to my second (currently unused) connections. I’ll wire the lighting gear to this shortly. I’ve purposely left things fairly adaptable since as per my intro I’m hoping to do some clever things with the switching down the line if all goes well. In a nutshell, the top two connections on the block are always live, the middle is to earth, and the bottom two are switched. You could get away with a SPST switch, but it's better practice to switch both poles.

BTW for safety I've earthed the fan case (it's a 230v fan in a metal chassis) and will also be earthing the ballast. Beyond that, most of the internal metalwork and the rear panel will be aluminium, so no need to earth these.

Day job kept me late (again :angry:) so not much of an update today. I installed the ballast on the RH panel (viewed from rear), note the earth wire bolted to the case for safety - you can't see it, but I attached it to one of the mounting screws with a lug (like on the fan). I also made sure I used all the screwholes since there's a lot of weight in this compoenent. Next job is to cut the rear heatshield so it fits around this. The good news is that it looks like there's enough room for the ignitor and the capacitor too in this area of the case, i.e. in the behind the heatshields and next to the ballast.
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Oh BTW I am postponing sanding, staining and varnishing the case for a while partly because I find it dull (prefer building stuff) but also in case I damage the case while installing bits. It will probably be the stage just before the LCD goes in.

Weekend is on the way don't know if I'll get much more done because I need to get some more metal sheet. I also need to source some lexan - there is a UK contact on this site somewhere, alternatively I have some pals that work in a glass shop who may be able to help...

I found myself passing a Maplin today, so got me one of these chaps:
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It turns out I haven't left mysef enough room on the rear panel for this , so it will be going on the side connections panel (which doesn't exist yet!) Possibly not a bad thing since this will keep it away from all the nasty high voltage components.

In addition to showing the temperature (there will be an external probe attached), this baby is also capable of showing the time, but perhaps more usefully triggering a couple of outputs at a preset high and low temperature, which is kinda interesting. These could be used, I suspect with a little electronics tweakery, to control the cooling fan. But I'd need to be sure I did it properly since I don't want to melt stuff! One of the dangers is that when power is disconnected (though you can fit a 1.5v battery), the maximum and minimum temperature settings are lost. Here's some more info you don't get on the Maplin website:

- Pin 1: 0v
- Pin 2: Set temp alarm on/off
- Pin 3: Set high/low temp
- Pin 4: Display test
- Pin 5: Select 10s or 1s update frequency
- Pin 6: High temp trigger (output)
- Pin 7: Low temp trigger (output)
- Pin 8: High or low temp trigger (output)
- Pin 9: Serial data out
- Pin 10: Serial data out
- Pin 11: Clock/thermometer select
- Pin 12: Show high temp setting
- Pin 13: Show low temp setting
- Pin 14: Centigrade/Farenheit switch
- Pin 15: Tempearture alarm output
- Pin 16: 1.5v

So I think there's some fairly neat things that could be done with this...

BTW can anyone give me some advice on how to run this from my 12V power supply? What I'm struggling to figure out is the current this thinhg draws varies, so that makes it kinda hard to pick a series resistor that would drop the voltage to the 1.5 I need . Essentially I'd look to drop 10.5V across the resistor and the remainder across this. Current is an average of 10nanoamps, though I guess if I fit an alarm as per the circuit diagram it will go up somewhat.

1.5V battery is fine for now!

It's tight for space , but I managed to get the capacitor into the rear of the box as I was hoping. This model comes with a built in retaining bolt, so with a suitably sized hold you can literally screw the unit into the side panel as I've done here:
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The terminal block provides a way of disconnecting this side panel if need be - once I installed the capacitor, it was no longer possible to acccess the screw terminals on the ballast. The connectors marked L and N will go to the switched outlet on my rear panel, and the B terminal goes to the ignitor. The ignitor itself will fit vertically next to the capacitor, bolted to the rear heatshield (need to make a fixing for this, probably out of aluminium). Once that's in place, the lamp electrics and cooling fan are all done. BTW you can see in the end I strapped the balast earth wire to the cooling fan chassis (the second red connector here). The ignitor will get similar treatment.

Here's the back panel installed in the case:
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I also did a little painting. The line where black meets pine is the position of the LCD panel.
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I still need to get some aluminium to move the build forwards (will try and drop by a metal merchant's this week) so in the meantime I have been having a think about the layout of the front of the box.

First it was back to CAD to draw in the LCD positions and light paths - took me ages since I don't really know what I'm doing and it's in 3D (though this image isn't):
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The yellow lines show the frensel positions and the light path, the vertical purple rectangle is the LCD, the horizontal purple box is the PCB connected along the edge of the screen, and the one at a slight angle is the main circruit board from the telly. This links to the edge connector board via a couple of FCCs, and all seems safe on that front (having had it aprt and back together successfuly , it still works! Here's a shot of the back of the panel (backlight still in place):
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I also specced out what my main connector and control panel is going to look like:
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This incorporates all the connectors I want to use, some buttons for the screen's main features (though more functions are available via the remote), the remote sensor, and controls for my fan circuitry (which may or may not come to fruition...) Another purpose of the CAD drawing was to check the spacing for this in terms of the ligh path - I have at least 85mm (worst area) so should be AOK!


Attached to the back of this in the case will be the TV module, which currently looks like this:
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This will be connected to the main board by a short length of 25-way cable using the existing DSUB connectors. I tried connecting a 1m parallell extension yesterday - it worked, but there was a noticeable drop in image quality, so need to keep this as short as possible. Using my proposed layout, the two won't be far away. The VGA connector is on the main board, so just needs a short extension from it to the panel socket.

Oh - does anyone have any suggestions for printing lettering onto aluminium? You used to get those transfers (I might even have somewhere) for making words letter by letter(!) or is there something more clever that can be done in this day and age?

Polycarbonate ('Lexan') arrived today from these guys:

http://www.davis-plastics.co.uk

Next day delivery, the material itself is faitly cheap, but postage was fairly steep on this. Spoke to a helpful guy there called Ross on 01293 552836. Mine is 4mm and the guys have cut it to exactly the size I asked for

I'm not sure if this has a UV filter as such like the XL10, I think it is more a case that the material is UV resiatant (time will tell). Perhaps this isn't such an issue sine the bulb I am using already has UV filtering glass (according to the packaging...)
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Hopefully I'll get hold of some metal before the weekend so I can start work on the heatshielding.

BTW the word 'POLYCARBONATE' is the only english on the protective film!

I've also been having a think about some of the electronics. Using a circuit like this one
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I think it should be possible to control the projector lamp from the LCD status (i.e. from the remote control). Using this design I simply substitute the opto-isolator for the existing power LED, therefore I hope the LCD circuit board should be happy with this. Everything else is in a separate circuit thus reducing the chances of me breaking anything. Probably a bit overkill, there would be simpler ways, but better safe than a fried circuit board.

Also the LCD effectively has two LEDs (though they are a single lamp), one for power on, and one for standby. With this screen, there is no LED in the completely 'off' mode when working as a video device. Using a dual opto-isolator and both LED outputs, I think I could activate the relay for either yellow or green lights like this:
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The remainder of the circuit on the RHS would work in the same way as my first sketch.

What do people think?

very nice.. I like this pic a lot, very clean

Dead easy with the rounding bit! I've actually got a couple of LEDs in store for the blank area of the panel, but don't tell

yup I know.. but my router is attached to a table and I'm too lazy to unbolt it up until now I haven't had a use for it other than making custom moldings so it's never been seperated! I use file + sandpaper

Having a somewhat rainy Saturday, so managed to get lots done today I'd planned to put my heatshielding in, but still don't have my aluminium so that's going to have to wait for next week. In the meantime:

First up, I cut the hole for my front control and connector panel. I had a feeling that something was going to go horribly wrong having nearly finished this side, but all went to plan (well on the outside of the box anyway
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The hole is cut with a router then smoothed using a rounding bit. The rear of the panel is then recessed to 7mm, like this:
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This hole is made in exactly the same way as the one on the rear panel, though it is a slightly different size.
Cutting a little oversize on the edges like this allows me to put a rectangular panel in without having to worry about rounded corners. Have a peek a few posts up to see the proposed layout of this

Next up, I cut two channels in the other side 5mm wide and 3mm deep, and have installed two sets of cables. The upper one carrys 230v from the mains input on the back panel to the LCD power supply. Connection is by IEC (I sabotaged the cable). The lower one is 6 core alarm cable which I will use for low voltage communications with the rear panel. I don't know exactly what I'm going to do yet, but I have a ground and up to 5 separate functions there.

Here's the wires at the front:
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And at the back:
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The rear cables will be covered with aluminium when I have some to stop it getting too toasty. Also for safety the earth wire is on top, so this would cook first if anything bad was to happen.

Finally for today, I have made a start on the optics.

First I cut two LCD/frensel holders from 22mm pine, and screwed these to the sides making sure they were at the correct poition and in line with each other.
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The rear frensel (which is clingfilm wrapped for protection) sits in the groove like this:
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I then cut two 5*22mm strips, which clamp the frensel in place:
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Lastly I instaled the polycarbonate sheet on top of everything. The holes were all drilled outside of the enclosure, since there isn't much space to work in otherwise.
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And we're all done, awaiting LCD! (lampholder and rear heatshield removed for clarity)
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Now, what's the view on having the top and bottom of the frensel 'free' like this? I am concerned that the lens may distort in the heat (though the two sides are held nicely). I have a plan in mind and some extra wood, so what do we think? Are you guys going to make some more work for me ?

Thanks in advance - Rich

Cant tell if you have made the holes bigger than the actual fresnel, I found with my first fresnel that i had to allow very slightly for them to expand or they would warp very slightly resulting in banana vision

Looking good so far though

Well my grooves are actually (and completely unintentionlly) a smidge too wide, so there is maybe about 1mm for expansion (0.5mm each side)

The jury's still out...

Just trying to choose a woodstain an the moment - there's a teak knocking around in the garage which I'm liking. As it stands the pine has a nice finiish but is just a little too anaemic!

OK minor update today.

I cut the air intake slots in the top panel. Each slot is 54mm long, cut with a 12mm diameter bit. The distance between each is 10mm.
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I'm really pleased with how the case has turned out I still need to make a ceiling/table mount, but I have purposely left this for now beacuase my suspicion is I won't want it pivoted around the middle, since most of the weight is actually in the ballast at the back. Look at how it balances on the table...
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I just need to figure out roughly where the COG is when I've installed everything

Finally I gave the polycarbonate similar treatment (though most sensible people would just cut the height down. I'll see how temperatures fare down the line... This picture is of course taken with the projector upside down.
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Next up I really need to get hold of my aluminium. I also plan to test the optics using glass and maybe some printed transparencies before I install the LCD and electronics. Talking of which the Relisys panel comes apart really easy - my only worry will be the antiglare removal when I get round to that. Otherwise, this unit is a pleasure to work with so we can probably add it to the 'approved LCDs' list, though it is a fairly dated model now.

Um it has gone rusty, so much for my aluminium theory! Never mind...

Teeny tiny update this eve

I have my aluminium now, so first up I have re-built the rear panel. I wasn't happy with my original effort, since there would have been some like leakage around the IEC connector. This one is much nicer plus now has the three indicator lamps installed.
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More to come this weekend hopefully

I've FINALLY got round to installing my aluminium heatshields

First I made a cutout in the lower panel for the ballast, then covered the rear hardboard panel in aluminium (0.8mm thick). The white colour is the protective film applied to one side of the material.
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Next I installed a short length of right angle section. This has numerous functions:

• Stiffens the back panel (it was a bit floppy before
• Gives me a mounting point for the lamp ignitor
• Separates the low voltage electrics (LEDs) from the nasty mains stuff
• I'll probably mount the reflector using this too!

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Finally, I boxed in the ballast - this was a bit fiddly, but I got there in the end
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Well I reckon it's time for a test run

Not forgetting to remove the plastic film, here's the lampholder installed with some temporary aluminium foil to protect the wood. I'll probably add some heatshields to the side walls too in the near future
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And she springs into life! My fan is currently connected to the non-switched terminals, and the lamp stuff is on the switch. Simple as that for now...

I was pleased with lamp leakage out of the fan - not too bad. Though I need to do something with the back of the LEDs since it looks like they're 'on' even though they aren't wired up!
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Need to do something about the light leakage here!
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I was hoping to try the optics this weekend, but I left my front frensel at work

Well British summer time ends today, so I get an extra hour of projector building time. So I made a start on the control and connector panel. Here it is with all the holes cut, and a few of the components installed. For now I have put black PVC tape behind the empty areas. It's pretty much complete on the outside (other than a stain/varnish) shame about the inside
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You can see how this is roughly based on this CAD plan:
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The round holes are no problem, the VGA connector and the temp module were a little more gnarly

This afternoon I put together the circuit board based on the designs earlier in this PLOG. And neither of the circuits works I need help - I know a man who might be able to
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EDIT: I never published a circuit for the fan controller - I'll knock one up now!

Here's the original electronics, as featured in my GCSE electronics book In circuit terms, it's a 'bistable'. The red numbers show the values of components I have used
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One change I made was to replace the switches on the inputs with transistors, like this:
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My plan was to use the ouputs on the temperature monitor unit to control the fan. From the bistable, one output would be connected to an LED, and the other output would be connected to another LED and a relay to switch the fan. I actually have a bi-colour LED (see the photos, it's the white looking one on the right) so both are in the same unit.

At the moment, BOTH my outputs turn on (though seemingly not at full voltage). From what I've read, when I power this up and ignoring the inputs, one of the outputs should go high, and the other low.

Any ideas/comments ?

OK going for the first test image today

First I installed the polycarbonate sheet and the rear frensel. It's a bit fiddly getting those holding screws in place with the heatshields installed, but it's do-able!
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Next I got my local glass supplier to cut me a piece the same size as the LCD panel. I have surrounded the edges with PVC tape, partly to protect my pinkies but also this shows where the actual screen image border is within the LCD mount. I marked the centre point using a couple of strips of clear tape
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The front frensel is held in place by, er, luck more than anything. This one is also still clingfilmed for protection while I work on it.
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And voila, a picture. Nicely in focus in the middle, though the light levels drop somewat towards the outside.
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This wider picture shows the issue better
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I am hoping adjusting the lamp position (haven't done this yet) will fix this. Also of course I haven't fitted the reflector, which can only help things

Update....

Pushing the lamp back does indeed sort out the edges - I just need to find the optimum position for it. Results in the intended place (i.e. 220mm from the frensel) aren't bad, it's just that I might be able to go even better than this.

One of the downsides of my lampholder design is it's kinda fiddly to adjust i.e. I need to swith the lamp on and off between each adjustment, which takes a good 10/20 minutes given the warm up and cool down time. I'm using my camera's expoure meter to check light levels, also photographing each option to compare the edge fading. Once I have the position sussed, it's reflector time