Sound card dac not working

[Grix]

I cannot get my projector to work with the sound card dac and spaghetti. I have assigned the projector and dac in spaghetti and I can hear sound from the sound card. But nothing from my projector. I also tried Laserboy, but that doesn't work either.
I tried troubleshooting with a multimeter, I measured a signal all the way to the correction amp, but nothing in the DB25 cable.

I bet the problem is something silly and obvious.. :yabbem:

 

[kiyoukan]

pics of the correction amp?
It could be put together wrong and not working.
or your dc to dc converter is not powering the op amps and if that happens it would act like yours.

 

[ElektroFreak]

If you can hear the sound coming from your computer speakers, then spaghetti's projector settings are not using the right sound card. You'll need to edit the "ezauddac.ini" file in the Spaghetti program directory in the "drivers" folder to use the right card.

Here's an example of the ezauddac.ini file:

[Sound Card Selection]
UseCardNumber=2

LowLatencyBuffering=no
;not all programs work smoothly with minimal buffering, try yes if you have a hyperthreading
; or dual core computer and like to try to speed up timing.
; yes works with zoof games, LDS, HE-Laserscan
; no works best with LazyMame, LFI player

SampleRate=48000    
;choose a standard samplerate that your card can handle 44100, 48000, 96000 etc.


RepeatFrameWhenOut=no
;'yes' or 'no'
;Repeats the last frame displayed if the program doesn't feed another frame in time
;  if 'no', then the DAC output goes to 0 until a new frame is fed.



[Channel Invert]
;enter 'yes' to invert the channel output, 'no' otherwise.
X=no
Y=no
R=yes
G=yes
B=yes
I=yes

[Channel Selection]
;Enter the desired output chanel number (1-8 only) of the signals:
X=1
Y=2
R=3
G=4
B=5
I=6
AL=7
AR=8

you can see near the top of the file where it says "sound card selection". Try changing this number between 1 and 2 (or 3 or 4 if you have more than 2 sound cards in the machine) until you find a setting that works.. Remember to save the file and restart spaghetti each time you change this value.

 

[kiyoukan]

From the post it sounds like he can hear music when he plugs into the usb card but it stops at the amp.

 

[ElektroFreak]

ahh, ok.. I misunderstood. I'd definitely check the voltages on the DC-DC converter, and double check the power connections from the 5V USB pads on the sound card to the DC-DC converter inputs.

 

[Grix]

For more info see this thread: How to configure spaghetti with sound card dac?

I don't feel like repeating it all.

 

[kiyoukan]

if the sound card is still working try hooking up your galvos straight to the sound card just for a bit if they move then you know its not the sound card.
i broke my first sound card.
ordered another one with prebuilt correction amp to save me the headaches.
if they dont move when you connect them directly then you know where your problem is a bit better. its hardware or software.
i use laserboy and it works great. try putting it and installing your sound card on every pc in the house and just for the moment set it as default so all sounds go to it and try again. i went threw 4 out of my 7 pcs before one worked.
if you hook them up straight do not do it for very long.
like i said i blew my sound card and don't know if it was this or my bad correction amp. i have a feeling it was my amp but still you only need to see that they move and be done.

 

[Grix]

I don't feel comfortable opening up a $500 projector. Also I tried it on another computer, same result.

 

[kiyoukan]

i understand your fear the only quick option would be to build an analog driver and put that on the outputs of the sound card and have it drive an led and if it works it will blink or fade.
Or send your scanner and sound card and someone with a working pc and correction amp and a sound card of their own and will test your unit.
it is a lot easier to send the projector then it is to send a pc and the driver setup.

 

[Benm]

If you are sure that the soundcard is putting out the signal (just connect headphones to it and listen), and you measure nothing at the output of the correction amp, it can only be the correction amp at fault.

Be careful with how you measure though: multimeters are not designed to read the high frequencies accurately. Still, you should be able to get some voltage reading in AC mode between the differential X and Y wire pairs when running a sample file at full deflection.

Otherwise, try to find a scope or someone that can borrow you one for a bit, those make diagnostics so much easier!

 

[Grix]

Be careful with how you measure though: multimeters are not designed to read the high frequencies accurately. Still, you should be able to get some voltage reading in AC mode between the differential X and Y wire pairs when running a sample file at full deflection.

Wait what. Oh right, analogue signals = AC, I've measured in DC current all this time...

I'll try to see if I can get some readings the next time I try.

Also now I actually get the projector to recognize something and it goes into ILDA mode when I plug the cable in. Still no laser output though..

 

[ElektroFreak]

Wait what. Oh right, analogue signals = AC, I've measured in DC current all this time...

I'll try to see if I can get some readings the next time I try.

Also now I actually get the projector to recognize something and it goes into ILDA mode when I plug the cable in. Still no laser output though..

You want to measure either AC or DC VOLTAGE, not current. That might be why you're not getting readings on the outputs..

 

[Grix]

I meant voltage.

 

[kiyoukan]

Is it working yet?