Having issues with gibberish output from Galvos

[bryce007]

Hello everyone,

I recently purchased some Scanpro 20's already hooked up with the correction amp and USB sound card. I've been trying to get them working properly with LFI player first, so that I can tell that they are working correctly before I buy spaghetti. I'm currently using Windows 7 32-bit, because I've heard from members that have had no issues using their galvos with 32-bit. I have tried using my dad's computer, which uses Windows xp 32-bit, and I've had the same issues as on Win 7 32.

Here's what I've tried.

1. I've got the audio driver installed as shown on Elektrofreak's tutorial
2. I've got the output set to 6CH on the sound card's control panel
3. I'm using LFI player version 1.1.6, using the EZAudDAC files from the 1.1.5 version of LFI.
4. The USB sound card is NOT the default audio source being used on the PC
5. I've opened the EzAudDac text file, which shows that the USB sound card speakers are sound card #2. Then I opened the EzAudDac configuration file, and made sure it was using sound card 2, and saving the document of course.
6. Then, I run LFI_Player_V1_1_6_EzAudDAC.exe file, and open a text document which says "Testing...Testing..."
7. When I hit the play button, I can hear and see the galvos moving, but when I shine a laser pointer on the galvos, no modulation as of now, all I get is some spikey lines that look like they're just moving along to a song or something.
8. Also, Elektrofreak had me test the DC-DC converter. I tested the set of three pins, and got +/- 9.10V with reference to the middle pin.

I also noticed, that I can't change the channel from 6 to 8 or something in the USB control panel unless the USB sound card is set as default in windows. Otherwise, when not set to default, the USB control panel still says 5.1, but all the channel buttons are grayed out.

I have tried setting the USB sound card to default, then switching to 8 Channels, and then setting my normal sound card to default and trying LFI again, I get the same results.

I was wondering if any of you had some ideas as to what might be my problem.

Here's some pics of my setup:



Here's what the galvos output when nothing is playing (idle):



The image looks clear in person, but blury because I had to hold the laser pointing to the galvos, and the camera at the same time.

I can post a video of the gibberish output if needed.

The reason I'm trying first with LFI player, is because I want to make sure the galvos are working properly with my computer/operating system before I buy spaghetti.

I appreciate any input

[The_Doctor]

That layout risks plenty of things going wrong. You won't get secure results till you have secure mounts and connections.

Some things to watch for:
Overheating scanners (though that looks like a thick black anodised baseplate so maybe they're ok).
Overheating scan amps. Those should be mounted to a solid heatsink.
Static damage to parts resulting from that bubblewrap. The air at this time of year is often very dry so this risk is serious right now.
Ground loops or other grounding problems, as some of those connections look insecure.

I guess that sound box has been modified to bypass the caps to allow DC coupling? (I also guess that's why the next board has amps and pots, partly to remove the 2.25V DC offset from the DAC's on those USB boxes.

[edison]

thats why you need a good solid case with a 10mm baseplate to keep things nice and cool

[MisterWilling]

You might read through this thread, its long but it shows me getting my soundcard DAC to work through trying different drivers. http://www.photonlexicon.com/forums/...62-Scan-Pro-40

[bryce007]

You might read through this thread, its long but it shows me getting my soundcard DAC to work through trying different drivers. http://www.photonlexicon.com/forums/...62-Scan-Pro-40

I'll look through it some more. I did see Lava's post with the pics his driver version, and my version is the same.

That layout risks plenty of things going wrong. You won't get secure results till you have secure mounts and connections.

Some things to watch for:
Overheating scanners (though that looks like a thick black anodised baseplate so maybe they're ok).
Overheating scan amps. Those should be mounted to a solid heatsink.
Static damage to parts resulting from that bubblewrap. The air at this time of year is often very dry so this risk is serious right now.
Ground loops or other grounding problems, as some of those connections look insecure.

I guess that sound box has been modified to bypass the caps to allow DC coupling? (I also guess that's why the next board has amps and pots, partly to remove the 2.25V DC offset from the DAC's on those USB boxes.

They were only on the bubble wrap for a short time. They've since been moved onto a thin metal plate until I get my baseplate.

[dave]

Test the DAC output with a cro and report back.

[The_Doctor]

They were only on the bubble wrap for a short time. They've since been moved onto a thin metal plate until I get my baseplate.

It doesn't sneak up on things during long quiet moments when your back is turned, it bites the moment you move stuff (even if all you do is lightly brush against it), and you might not see, hear or feel a thing, and it could still destroy sensitive electronic parts. Just putting them on that kind of plastic in a dry climate like Arizona's is asking for trouble, a microsecond could be more than long enough.

You probably got lucky because parts already assembled into boards get some protection if the design is good, but best keep the expensive delicate stuff properly protected from static at all times, because static damage is hard to confirm and expensive to eliminate. But very cheap to protect against.

Edit:
If you're ever handling static sensitive parts, one of the cheapest ways to do it is to close the doors and windows and boil a kettle. Wait till the air feels thick with humidity, but turn off the kettle before you see condensation on things or a room full of steam. At that point you can handle the parts as normal, just make sure they (and their packaging, if it's not designed to shield against static) are settled in place not to be moved or touched again before you let the room get dry again.

[ElektroFreak]

And for those who might not be electronics experts, a "cro" is an oscilloscope.. although I don't know if you have one bryce.. That would help determine if the problem is the DAC or if it's your galvos. Normally the galvos are tuned from the factory, so most of the time DAC wiring is the culprit.. One thing I did notice in your pic you showed me is that you are feeding the galvos on their positive and ground wires (red and black). Try giving them signal on the red and white wires, red + and white - (leaving the ground wire [black] disconected) and see if that does anything for you.

[edison]

My first guess was a crowbar

[drlava]

I was looking at that galvo connection, too. make sure you have connections:
G-Black
6-Red
G-Black
5-Red
and ground the white wires to G also, leaving them floating could lead to that noisy loop you posted.

In your first photo it looks like you skipped the first G socket. You must be detail oriented while wiring.

If you are using the same driver version as I posted, you should be able to change to 6 or 8 channel mode even with the sound card as secondary (or tertiary, etc) in XP.