Labview over soundcard

[n00bzor]

Hey, i have a couple of questions, maybe you guys can awnser them :

1. What maximum voltage should i expect out of a sound card (i'm thinking 12v depending on the wave)

2. Maximum amperage (no idea, also thinking it depends on the wave, i need a maximum of 10mA to switch three optocouplers)

3. How exactly should i generate a waveform to obtain a certain voltage? Is the amplitude of the signal the same as the voltage?

Thank you in advance.

[Dan DeFriese]

QUOTE (n00bzor @ May 25 2009, 10:03 AM)

Hey, i have a couple of questions, maybe you guys can awnser them :

1. What maximum voltage should i expect out of a sound card (i'm thinking 12v depending on the wave)

2. Maximum amperage (no idea, also thinking it depends on the wave, i need a maximum of 10mA to switch three optocouplers)

3. How exactly should i generate a waveform to obtain a certain voltage? Is the amplitude of the signal the same as the voltage?

Thank you in advance.

You should really look at the specs for the given sound card. Generally, they'll only produce enough power to drive a set of headphones (.5-2Vp-p). What exactly are you trying to do? (Beyond destroying a perfectly good soundcard )

Obviously, cost is an issue for your project, but if you more some more specifics maybe someone here can guide you to cost effective solution. Perhaps using a parallel port (one of those USB adaptor kind if need be) or $10 demo module from ftdichip.com would be more appropriate.

~Dan

[n00bzor]

QUOTE (Dan DeFriese @ May 27 2009, 01:59 AM)

You should really look at the specs for the given sound card. Generally, they'll only produce enough power to drive a set of headphones (.5-2Vp-p). What exactly are you trying to do? (Beyond destroying a perfectly good soundcard )

Obviously, cost is an issue for your project, but if you more some more specifics maybe someone here can guide you to cost effective solution. Perhaps using a parallel port (one of those USB adaptor kind if need be) or $10 demo module from ftdichip.com would be more appropriate.

~Dan

The soundcard is a really cheap one, somewhere in the 10-15$ range, i don't really understand how using a parallel port to usb would help. I'm trying to run a transistor circuit/optocoupler circuit, i've already tried everything and i think the main problem is the 6009's power output on the digital ports (on analog it controls the circuits perfectly). Problem is that i need 5 control lines out of the daq, and i only have 2, so some form of multiplexing isn't an option also.

[jdunham]

QUOTE (n00bzor @ May 27 2009, 12:55 PM)

The soundcard is a really cheap one, somewhere in the 10-15$ range, i don't really understand how using a parallel port to usb would help. I'm trying to run a transistor circuit/optocoupler circuit, i've already tried everything and i think the main problem is the 6009's power output on the digital ports (on analog it controls the circuits perfectly). Problem is that i need 5 control lines out of the daq, and i only have 2, so some form of multiplexing isn't an option also.

AFAIK, most sound cards are AC-coupled. So you can't just leave them at their max voltage if you want to keep a switch on. I don't think its a practical way to control a digital output.

The standard parallel port contains discrete TTL lines. More information is here. If you don't have a built-in parallel port, you should be able to find a USB one for about US$15.

These are a bit pricier (US$100), but would be easier to work with

http://www.phidgets.com/products.php?category=0

If you want to have a lot of fun, you should ease into something like the Basic Stamp

Let us know what works!

[Dan DeFriese]

QUOTE (n00bzor @ May 27 2009, 02:55 PM)

i've already tried everything

Impossible! It doesn't work yet.

Post what you've tried.

QUOTE

and i think the main problem is the 6009's power output on the digital ports (on analog it controls the circuits perfectly). Problem is that i need 5 control lines out of the daq, and i only have 2, so some form of multiplexing isn't an option also.

Are you saying that you have one of those NI-USB-6009 DAQ gizmos? Are your optocouplers really drawing 10mA (This is 2x the rating of the 6009 analog outputs so I'm puzzled.) What is the part number for your optocoupler? Maybe provide a drawing of your setup? Is an external power source available to power a simple transistor amplifier stage between the 6009 and opto. Maybe this could be powered with the 5V 200mA power source from the 6009 itself?

~Dan