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Sound card DAC tutorial

laser15

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,
Are you able to post or PM me pics of your DAC setup and screenshots of your audio card settings? Hardly anyone ever does that, but I'll ask anyway since they would be absolutely golden in terms of helping to diagnose problems.

I have finished my correction amp today.
I am very pleased with the results, even without blanking.
I will try to post some pictures soon, if someone can explain to me how to do it :D

@ElektroFreak: I have solved the crosstalk problem.
 
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bennett326

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i finally got my dac working but i have no out put out of lfi i turned on lasers and changed the sound card from 1-2
 

ARG

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Does someone know what's the problem when the galvo's are ticking?

I had the same problem when setting up my first pair of galvos with an SC DAC. Don't run your galvos anymore until you are sure your DAC will not wreak them.

Test your DAC on an o-scope if you have one, or have access to one. Make sure you are displaying the ILDA test pattern when trying to test your galvos.
 

laser15

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Can you be more specific? They do a strange sound when running, indeed, but are they moving at all for you?

They are moving normally (I can draw the ILDA pattern easily) but there is a faint tick every now and then. It is different in every frame I play in LFI.

Problem fixed. One of the ground connections from the correction amp was loose :D
 
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Elektrotechniker

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It's a start :) LOL
377444_2247634038178_1468000771_31893912_371569_n.jpg
 

laser15

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I had the same problem when setting up my first pair of galvos with an SC DAC. Don't run your galvos anymore until you are sure your DAC will not wreak them.

Test your DAC on an o-scope if you have one, or have access to one. Make sure you are displaying the ILDA test pattern when trying to test your galvos.

The weird thing is that they don't do it always, sometimes they work normally and sometimes they tick. I can't seem to find out what it is. There is a fan next to the signal cables but if i disconnect it. it doesn't make any difference.

UPDATE: I have found the source of the ticking: It's my laptop. If i listen to the soundcard by headphones I can hear it tick. It's less frequent if i switch my laptop to ''high performance mode'' does someone know why this is happening?
 
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sputnick

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Hi,

I have ordered one of the Murata DC-DC converters to use with the correction amp detailed on page 2 of this thread. Not used one of these before so I am unsure how to wire it.

This the pin out for the converter:-

Pin Function
1 +VIN
2 -VIN
4 -VOUT
5 OV
6 +VOUT

Obviously 4 & 6 are the output, just not sure which inputs I should be wiring (1,2 &5) would I just wire the vcc to 1 and ground to 5 (ignoring 1 -V in)?

Thanks,

Phil
 

Things

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1 is your + input
2 is your negative input
3 is your negative output
5 is your output ground
6 is your output positive.

Only 2 pins are inputs, the rest are outputs
 

sputnick

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So, if I'm using getting the power from the USB connector on the sound card, then USB ground is the negative input(2)?
 

Bionic-Badger

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Yes, that is correct.

USB +5V -> VIN +
USB GND -> VIN -

Pin 5 is zero volts which technically shouldn't matter in the design; however, I would tie it to the other grounds.
 

laser15

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Does someone know what's the problem if the laptop is causing the soundcard to tick? When I listen to the soundcard it ticks about every second if I set my laptop in power saving mode. It ticks less when I set my laptop in high performance mode.
 

ARG

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Does someone know what's the problem if the laptop is causing the soundcard to tick? When I listen to the soundcard it ticks about every second if I set my laptop in power saving mode. It ticks less when I set my laptop in high performance mode.

Tick? Coming from the sound card itself?
 




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