Your cooling fan could always 'break'

The above was a computer related issue. The video card was overheating.

Now, however, I've a weird problem, and it's one that doesn't show too well in pictures.

Since, I have family coming in town, I thought, "Hey, I'll take the projector down for a good cleaning." I did so, but when I put it back up, I noticed a large "U" shaped brownish discoloration in the middle of the very top of the screen. I thought I must have missed some dust since it looks somewhat like what dust build ups can look like. So, I took the projector back down and inspected it. No, dust. I noticed the pro reflector was a bit dirty and decided to clean it. Oops.

Anyway, the new reflector is here, and the projector is back up. But, the brownish discoloration (with slight focus issues) is still there. It doesn't really show up in photos (I've tried).

Any thoughts as to what this might be? Other than this the projector is working great. Go figure.

R

I'd check the bottom of your projector. It may be a wire that's entered the light path.

Darned good idea. I'll do that. Thanks!

I checked and unfortunately that wasn't it. I did manage to get a picture, though. Any thoughts?

I haven't gone back to see what bulb you have or anything, but have you looked at that in any way?
I know a lot of mogul bases will allow the bulb to drop slightly if mounted horizontally. Did you maybe bump something?
Does the arc chamber on the bulb look ok?
Also, like I said I haven't looked, but, your triplet couldn't have been moved so it is now tilted in any way could it? All speculation, just thinking of things it could be. But, it does sort of look like a shadow, like something in front of the fresnels or lcd is in the path.

I'll go back and recheck everything you suggested, thanks. It is an odd shadow of somekind. The picture is noticeably washed out and blurry in the brown area as well.

I'm using the new bulb mounted horizontally, btw.

R

I think mine does that too when my bulb is bumped too much. My bulb can move alot in its base

Then messing with my bulb is my next step. Right after I get tired of playing Guitar Hero on the projector.

Fixed this by readjusting the bulb position, make it more horizontal. I think it must have slipped over the past year or so.

But, now another prob - any ever have their screen repeatedly bleed white on them, i.e., go blank? I don't think it's heat but I could be wrong. Could the lcd be going bad?

After running the projector for several hours last night using the xbox 360 as my source, I'm pretty convinced the problem lies in my computer. I imagine the video card is going bad. It was a cheap one to begin with.

Extremely belated update: My video card died on me. All is well now.

Next up - HD!

Next up 575 watts from Jonjandran

Anyone know how to wire one of these things?

Did you unhook the two wires I had hooked up to the ballast? The black and white?

They hooked to the two far left pins on the ballast as you are looking at it like in the pic and then you wire them to 120v. Either wire to either wire , because it is AC

You then can add an inline switch and fuse

Thanks!

When it gets here, I'll take a look at that. I'm just doing my homework, now.

That's right I just shipped it.

Boy when you ship 20 things in a week , you get lost.

I also need to know if this effects cooling - I have 2 120 volt fans on the back. So, I doubt it, but I want to be safe.

It's here! Arrived in great shape and earlier than I expected! If all goes well, I'll be viewing with 575 goodness this weekend.



So, what do I need to hook these up to? Why not just to a plug?



Jon - how'd you have this mounted? Not sure what to do about the angle. I'm sure I can compensate with screws and bolts or wood; just curious.

I plan on using this to project through a 15" monitor (hopefully the UXGA Crazychen's got but definitely my current one). What do I need to change or do differently with it to do this?

Go ahead and just use a plug. Just don't complain if it burns out one day because you were to lazy to put an inline fuse

Just get rid of the angle by redrilling and mounting the precon. See those screws on the side. Just redrill them to where it is square.

Well, if you put it that way - what kind of fuse should I wire in? I know nothing about fuses.

Well, if you put it that way - what kind of fuse should I wire in? I know nothing about fuses.

Also, will this pre-con result in some extreme vignetting?

What size should I get for a 15" lcd?

Another question - right now, I'm planning on mounting the light in the same position as the 400 watt bulb. Should I recalculate any distances?

Also, can I use wood to mount it? Or does it get too hot?

Jonjandran recommends I use a metal mount, which makes sense given the heat this thing will probably give off. This'll be a challenge as I no longer have access to metal working tools or a band saw.

So, I'm thinking of creating a platform out of sheet metal that has been spray painted with furnace paint that is mounted on threaded steel rods to the correct height. The ballast would be bolted to that.

Sort of an inverse of this with longer rods. Thoughts? See blelow.

Also, I want to splice this wire into the circuit for my temperature switch (see pic immediately above). Is there anything special about this wire I should know. Will the wire I used for this purpose for the 400 watt bulb work?

Rummaging through my junk drawer I came across some "L" and "T" brackets and a box of nuts and bolts. They all looked to be about the right height. So, I decided to tinker with and come up with this -

PIC 1) I had to drill out the holes on the aluminum frame as well as adding two more holes for the "T" brackets.

PICS 2 & 3) Another challenge I faced is the light box is angled. I need it level. I leveled it off using nuts.

PIC 4) Bottom view of supports

This is an eyeballed placement in the projector - not too bad.

Finished full view & Friend (Louie from Douglas Trumble's Silent Running)

I'd like to splice one of these wires into my temp circuit. Does anyone know if there's anything special about them that would prevent me from doing this. This is the only thing keeping me from completing my wiring.

Wired up the box tonight and lit the lamp. The wiring and all worked just fine. (update: the cord for the lamp is slight warm)

There's heavy vignetting, but I was expecting that.

What I do not know how to deal with is the unexpected heat issue - 116 degrees before I cut it off - which was less than 3 or 4 minutes.

If I pop the front lid the temperature falls quickly so I need to investigate the air intake. Has anyone put one of these in a diy box, yet?

1st Picture - the inside -

2nd - the rear -

3rd - side view -

4th - 1st burn with no lenses -

5th - Lamp on with lenses and lcd - vignetting as expected - should I remove the precondensor lens?

6th - And, finally - the bad news - it's too damned hot - 116 degrees

This thing is darned bright - pics to follow. Heat is less of problem, now. LCD temp stays between 89 and 91 degrees, but, wow the ballast gets hot (150 deg + surface temp).

Had an issue yesterday with the heat switch being triggered. I think it was the ballast heating the wood. I had the ballast flush mounted, but last night I mounted it 1/2 from the side of the box so that there is air on all sides. I was then able to run the projector in a test for 3 hours with no problems.

I'll be reinstalling the projector up top, tonight and will take pics.

There is also a weird bright spot in the center of the screen that is there no matter what bulb I use. Anyone know what that is?

Like I said, pics to follow.

Hmmm - darned thing cut off again (yay heat switch!). It only does this when up in the box, which I'm thinking means the air up there is a bit warmer. I'm also wondering if there's not some exhaust air recycling. That would heat things up a bit.

The following were taken between 6 and 6:30 this evening. The room gets direct sunlight through two windows: one to the side and one directly in front of the screen in the kitchen. Some of the pictures have the side window closed off but all have the kitchen window open (mainly because the blinds fell off).

Doctor Who - Drapes open and then, drapes closed.

And, one from I am Legend (720p matroska file on the 1024 x 768 monitor)

And, now the slightly annoying white spot

Full Screen and Circled

(I don't know why the board posts pics like this - combining them into one post and then, out of order) Can't say I like it much. I'm sure I'm doing something wrong, but I'm tired of trying to fix it. Oh well)

White spot on Abigail Adams

if I remember correctly people were having the same problem (small 575 bulb) because the center of the fresnel lens are not "perfect" at the center it has that dimple I think thats what you are experiencing. Just my 2 pennies.

Cool - I hope that's it, because that's easy! Thanks. I'm about to redo the fresnels anyway - I've got major linage.

what does that mean "thats easy"
I dont think there is any way to fix this.

Sounded like it was merely a matter of adjusting the fresnels. Compared to wiring and carpentry and cooling the box, it sounded comparatively easy. Also, the spot doesn't bother me that much.

Make sure the little dipple on the lamp is either mounted up or down in your lightbox. You probably did but you never know. I use the same lamp and got no problems of white spots, also don't think perfect allingment of your fresnels will do you any good. I know mine is not prefect.

It is. Thanks!

Still having cooling problems. I think I'm going to move the thermal switch about an inch closer to the lcd and see what happens. I'm also considering a 3rd fan to force air into the box.

Moving the thermal switch didn't help. So, I'm going to get a fan and force air over the lcd. After that, I guess it's time to start opening up the box and putting in more fans.

I'd like to get this solved as I want to put a 15" uxga monitor in it, but not until I've solved the heating problem.

The hot spot or white spot seems to be fairly common especially with the 575HMI. I've learned to ignore mine as well. Great job on the PJ! The heat problem absolutely can be solved. Just keep at it.

The white spot doesn't bother me anymore, and I'm going to get cracking on the heat problem. Bought 3 small fans at Frys this morning.

Thanks!

Ok - Cut a hole in the rear lid (there's a front and a rear lid) and put the three new fans across it. The hole is only slightly smaller than the fans. The lamp stayed on for about an hour and 45 minutes.

I'm thinking I'm going to cut a hole in the bottom of the box in order to allow cooler air to be sucked into the lamp area.



Proposed air hole. The fans sit above and just to the rear of the lamp. So, this might bring air in and over the lamp to cool it.

On a happier note: I bought an Xbox 360 HD DVD player and 6 hd movies yesterday for $60. There are several hundred hd dvd's already released and while I am planning on eventually getting an internal Blu-ray drive for the pc. The HD DVD's are now about 6-12 dollars a piece online. So, this is a cheap way of going HD in the short term.


My HTPC is now an HD HTPC as the drivers for the player are readily available and it works on pc's. The picture is phenomenal - even on a my 1024 by 768 monitor. As soon as I have the heating issues solved I'll put a UXGA monitor in the box and really enjoy the pics. I do have a composite out to my tv. So, I can see the vids at 1080p, but it's not the same as on the projector.

Cut the trench and all is well.

Now, you can land planes by the light it gives off, but that's more of an aesthetic issue as it doesn't interfere with the projection in a noticeable manner. I have a couple of ideas as to how to solve that, too.

Well, heck. After days of running it for hours on end, it cuts out tonight after a mere 3 hours and in the middle of a great battle in Troy. Hopefully, just a fluke. We'll see.

Rot Row Roorge!!!

I will send happy thoughts your way. Hope it works out.

Ditch the thermostatic cutoff switch and monitor the temp at the LCD. As long as it remains within tolerances, you're OK.