New diy RGB scanner

[DaftPon3]

So i have been looking into making my own laser projector and this seems fairly reasonable to help me start and on my budget. but like tadawson i am waiting to hear if it is ttl or analog. im only trying to get a kickstart in laser projection and this might help if its worth it.

[dooiespons]

Sorry for the late reply, i've been busy the last couple of days

Here's a copy of my latest post @ LPF:


Pictures:
Testing the lasers & galvos.


Inside of the case (testing) :


Front view of the case:


Rear view of the case:
The ilda connector already built in and a test setup of my audio dac connected:

(The potentiometers are for adjusting the strength of each color, to get a good white balance)

Testing some beams with the audio dac:



And the projector in action in a club! (With Quickshow)
The pictures are a bit bad... but it's really hard to take good pictures of a laser with a camera phone.

Beams!


Projecting images onto a LED-pillar.



Beams, seen from the outside.

(The beams were also clearly visible in the club across the street )

Small rainbow wave.



HE-laserscan just didn't work for me with the audio dac.. i had some major issues (circles not being circles, green blanking delays, color swapping).
So i decided to borrow quickshow, and it worked perfectly. No problems whatsoever
The galvo's are only 20k though, so bigger art flickered a bit when i projected it.


The analog modulation works great, i've made a few rainbow waves in the club and people went crazy!
The only thing you have to do is put a jumper over the TTL pins, and connect the the analog input to the modules.
No delays, and the colours are really good.
For me this was the perfect start: cheap, easy to use, and not much trouble getting the alligment right.

The red beam however is 'fat', it doesn't fit fully on the mirrors (7x11MM).
I think im going to replace that one for a new 635nm sometime.

Small video:

I turned it on about 5 seconds into the video.

[Datsurb]

Impressive result. Looks like you got the alignment sortet out pretty decent too. What kind of ILDA board did you use?

[Mlenox]

I'm curious as to what sort of power it's actually pushing versus what's claimed.

[Datsurb]

I have ordered and received one of RGB modules togheter with This Galvo/showcard set. http://www.ebay.com/itm/40Kpps-Hight...-/170589507384
The module was extremely out of alignment when i received it. (Looked like the laser Gunsight from the Preditor movies), but my Dremel did the job with the Epoxy and adusting the dicros gave a dicent result.

However, it only works when using TTL. No laseroutput at all when shortening the TTL jumper on the LASER PSU, and hooking up towards the analog jumpers.

My guess is that the showcard from the galvoset only supports TTL, but the seller confirmed that it also supported analog as long as i did not use the buildt in auto/sound functions. I got the showcard to be able to make all cabling as easy as possible, but my limited knowlage in the difference between analog and TTL is haunting me.
I would be a happy man if anybody could explain what to take into consideration when doing analog cabeling vs TTL. I understand that TTL is digital 0-5Volt = On-Off, and that analog is 0-5volt =0-100% laser output.
If any more info is requred to explain, please let me know, and i will fill in.

Update. I found the correct word for what I am looking for, and a ILDA breakout board is the thing. Anyone know if it still is awailable from forum members?

[dash8brj]

To check the 5V analog modulation on these, just hook the two ends of a 10K pot to a 5V power source, and the wiper to the analog input's +. Ground the other side of the analog input to the 5V supplies ground.

Now you can simply adjust the pot to see if it has analog modulation.

...................10-100KOhm
+5V--------/\/\/\/\/\/\----------GND
......................^...........|
......................|............-------ANALOG MOD GND
......................|----------------ANALOG MOD Input.

If you ignore the .'s in my crappy ascii schematic, you can see what I mean

Make sure to wire the fully CCW end of the pot to the ground, and the fully CW end to +5V (my schematic's fully CW end is at the left of the pot)

[Datsurb]

Thanks mate! I will try that. Not a wizard in electronics, but this seems to be managable. This will tell me if all modules are analog.
I have ordered a ILDA breakoutboard from Stanwax, and hope that will eliminate the need for PT sowcard, and at the same time save me from a lot of microsoldering directly on the DB25. The projector have been working as a charm, and i look forward to be able to get it to produce more colors and the fading laseroutput as well.

[Datsurb]

A small update on this case:
I discovered that the PT-Ishow card handles analog modules without any issues. If you want to use the onboard show inside the card, (also controlled by DMX), then it will function as TTL, but with QS and Spaghetti as i use, it works perfect with analog modules. Thanks again for all help from dash8brj.

[Bradfo69]

dooie...

Just an observation. You're doing a fine job a learning about building a projector. But, I must also suggest you read some of the threads on laser safety as well. The fact that your beams are even going into the club next door isn't necessarily a good thing. Particularly when you are working with cheaper gear prone to failure. What you DON'T ever want is to be responsible for an eye injury should a galvo go bad and send a hot beam where you DON't want it, let alone the lasers running as they are. You really should think about keeping those beams overhead and watch where they terminate.

[Datsurb]

I just joined the same thread as i was buying the same RGB module. Safety is of course a big issue playing around with lasers, and that was the main reason for me to go analog. The possibilities of reducing output to minimum or none if there is a possibility of croudscanning is essential. I have spendt quite a bit of time reading PL posts, and have now a far better understanding of laser safety and how to use then proper, than prior to my time on PL.