The entire thing would involve a few components on a board with a cable connected to the sound card in your computer, plus another cable going to a 12V wall wart-style DC power supply plugged into the wall. If the external DC power supply is unacceptable, your computer PSU supplies 12V to half the components in the PC. Just grab one of the molex connectors coming off the PSU and use the 12V off that! ( I prefer not to screw around with my computer's power, but there's no reason why it shouldn't work-- you'd have to be pretty careful though, since the computer PSU can supply a helluva lot more than 100 microamps )...
Operational Amplifier... $0.56
DC Power Supply... $9
Breadboard... Priceless
Seriously, you can do it really cheap. For under $100 you could even have a custom PCB printed and solder your components to it! The cleanliness of the signal would depend almost entirely on the sound card, but I can't speak to that quality. Can't hurt to hook something up and take a look on the 'ol oscilloscope, though.
~John
On 3/15/06, as <[EMAIL PROTECTED]> wrote:
hi,
thanks for the suggestions, but there are a couple more constraints. this is to trigger an external camera that accepts 0-12V trigger and needs ~100 uA of current. ideally i'd just like to avoid an external circuit and especially the power supply for such board. the perfect solution would be a board and a ethernet cable plugged into that board.
the signal needs to be clean and be close to 12V (if a sound card is used, is it possible to specify the output voltage?)
i'd like to keep the cost to under $100.
aravind.
On 3/15/06, John Demme <[EMAIL PROTECTED]> wrote:I would be pretty trivial to build use an op amp to get up to the 12V. Plus, with a sound card, you get two channels (more if you have 5.1 on your computer)... Writing the software to output waveform data to the sound card would be interesting... Better yet, you could probably just use a program to generate an x Hz waveform in wav format and dump that to the device.
