need help planning my projector

[cruch]

jkaiser3000:
didnt you get an 25 pin connection with easylase?

[jkaiser3000]

didnt you get an 25 pin connection with easylase?

Yes, I did, I just didn't see the use for it with so little wires being used, besides, at this moment I don't have the male to connect everything to. For that I have to wait for stores to open, probably next week :roll:

does decreasing the pot to tiny make the image small and big if you turn it the other way?

Yes, it does, but apparently more so in one direction than in the other. I tried this test with the ilda test patter once, and when the pot was lowered, the image was almost a point, well, very small . When increased, the Y axis was very big, too big I'd say, while the X axis was significantly smaller.

Is the beam centered and stable with no inputs plugged in?

Yes, absolutely stable. Things start getting weird once a signal is sent to the scanners. For instance, with everything powered up, I can hear a high pitched sound from the galvos, but very low volume, barely audible. This is with mamba not outputing anything, and the beam does not move. When I play a frame, everything goes haywire. You can see this effect in the video, when the laser is stopped, it's because I stopped mamba, with everything still connected and powered up.

try it by touching the two leads of the input (where you plugged the pots in)

You mean with the galvos connected to the PSU and scanamps, and no pot (sort of like shorting the two pins with my finger), and mamba not outputing anything. Is that correct or did I missunderstand you?

It really looks like you are shorting the (-) lines of the X and Y to ground...

Well, it's just the image. The lines are not shorted, maybe the effect is due to the angle the pic was taken at, the use of flash, and the use of a low quality digicam, and most certainly, a lousy job at soldering . I seem to have misplaced the multimeter, so I'll look for it first thing tomorrow morning and try that just in case. (I'm willing to try everything :lol: )

To clarify, your 4.7k doesn't look like 4.7k

They're marked 472, is that 4.7K or am I mistaken? ops:

Again, thanks for your patience

[jkaiser3000]

I just tried the use of my fingers as signal generators and it does produce a straight line when used in only one galvo, and a slightly tilted and elongated figure eight when both scanners are used. No DAC connector for obvious reasons (well, you could say my finger was the DAC :lol: )

[yaddatrance]

Can you measure the resistance between pin 14 and 15? It should read somewhere near 9.4k

What I'm suspecting is that you're getting noise back from the ground lines.

I know it's a pain, but you might want to remove the 4.7k ohm resistor and leave
pins 14 and 15 floating to ensure the lines are isolated from each other and the
ground. The 4.7k is used to keep the opamps efficient, removing it won't damage anything.

[liteglow]

send me the USB and I configure it corretly I have 2 of them already...

But on my first try I did NOT solder the X and Y resistors, and the galvos was going like mad..
So that can maybe be your problem...
If I remeber corectly it is 2 ways to connect this system.
Closed loop and something else :roll:
But anyway, make sure the resistors are corect!
And that all the single ends are soldered to resistor, so there is no free wires going into nowhere... i think it was..

I think it`s the same as yadda says it`s all in the Easylase manual pdf

[jkaiser3000]

Ok, tested the resistance, and each resistor is 4.4K, although they're marked 472 :roll: . Total resistance between pins 14 and 15 is 8.8K. That means they're not shorted. Damn, I was hoping that'd be the problem, y'know, easy fix

I'm going to try now connecting the galvos directly, without the pot. and then taking the resistors out for another test drive. I'll get back to you

P.S.: one thing I found though, is that the resistance between the intensity wires (pins 3 & 16) is around 10K, is that normal?

Edit: if I take the resistors out, do I connect the galvos' ground directly to pin 25?, don't I need to short pins 14 & 15? I'm guessing I do, just want to be sure

[yaddatrance]

The 10K is a simple pulldown resistor for the intensity. That's normal.
Leave pins 14 & 15 floating for the test.
Scanner ground should go to pin 25.

Let me know how it goes. Also, what software are you using? that may have an effect.

[jkaiser3000]

Ok, here's an update. I tried everything againg as it was with resistors and all, but with mamba not outputing a show. In effect, no signal going to the galvos. I did this to test what would happen if I turned the pot. The laser was projected onto the screen and as I turned the pot up, the dot moved down. All this time it's making a barely perceptible hum, but when the pot was all the way to the left (off position), the hum was gone. There were no signals coming from mamba, but it was still connected to the amps, and it was running in my computer, just no shows running at the time of these tests.

Then I took the resistors out and checked without them, with ground hooked directly to pin 25. No jumpers shorting pins 14 & 15 to GND either.

Tried with a simple circle and it produced a somewhat distorted circle. More oval than circular, and some spikes on the bottom of it. Also, I noticed the image is pointig a lot downwards. I have the galvos on a temporary table, and the circle was projected onto the table, just a few cm away from the galvos (I'd say 1 ot 2 inches from the galvos block to the bottom of the circle). Also, the more I turn the pot (yep, I'm still using it :roll: ), the more the image shifts downwards, or closer to the galvos.

All in all, I feel this test with the galvos connected to pin 25 and pins 14-15 not shorted gave somewhat better results. The fact that the circle appeared oval was probably due to distortion as the image was projected on the surface of the table, oblique to the laser's path. And, it was more open than before (less of an oval, if you will, and more circular).

In case you need to know, I'm running mamba 2004 on win XP SP2, and the usb cable I'm currently using is the one that came with my printer, seeing as I didn't get one with the easylase. That cable is connected directly to the motherboard, no hubs in between

P.S.: Phillip, thanks for the offer, but I would like to know for sure that this problem lies with the easylase. No sense in sending it over if the problem is on something else (could be software, amps, galvos, PSU, misbehaving computer, etc)

[yaddatrance]

Ok, we're getting somewhere... with the easylase disconnected, hook a 1.5V battery to the inputs on the board.
See if it cleanly moves the point, then flip the battery (reverse polarity)... do this with both axises...

The skewed oval makes sense since you removed the resistors. Can you post a pic of the oval?

[jkaiser3000]

ehh, what input, on what board?. you mean where the 9volts are usually connected on the easylase?, or to the scanamps?. I'm sorry, didn't catch that one ops: