USB Audio DAC mod + LaserBoy Correction Amp

[DPSS]

I think Andrew is right - the ScanPro 20's are probably running as wide as they can with the single-ended output of the sound card correction amp. (Differential signaling will give you 4 times the peak-to-peak voltage.)

You could upgrade to a different controller that supports differential output, or you could live with the smaller scan angle...

Adam

I don't think I agree with you, if that was the case it should be the same on both channels and it's not.

when i play wave files i gat a SUPER WIDE scan angle. when i play it thru spaghetti its WAY SMALLER.. i think it may be something in the driver or spaghetti.

I've tried the test patterns in HE Lasescan and they're even smaller and the wavs I created with laserboy are about the same size as in Spaghetti. I'm not sure though of how to change the scan angle on any of the two programs.

Is there any way you can send me one of your SUPER WIDE scanning waves so I can try it myself?

Twice, +/- 5V verses +/-10V, or 10V peak to peak with single ended, 20V peak to peak with differential.

My ScanEco 30's have enough adjustment range to do fine with +/- 5V single ended, so I wouldn't expect the scanPros to have an issue, but it's possible that's why you should ask the seller.

I'm still waiting for Dave to answer the pm I sent him a couple of day ago. I'll try contacting him again, also thru his web page.

Domingo.

[keeperx]

here is a nice wide one

[DPSS]

Thanks keeperx.

I get the same scan angle as with mine.

[keeperx]

ok well i guess that everyones setup differs..

[DPSS]

ok well i guess that everyones setup differs..

Which exactly is your setup? maybe if I compare it with mine I'll find something.
I'm still trying to get hold of an oscilloscope to take a better look at everything.

Domingo.

[DPSS]

I just received a reply from Dave to the mail I sent him yesterday and, unfortunately, he can't offer a solution due to the many unknowns using the USB DAC and software. He has offered the possibility that I send them back for repair, but doing that without knowing for sure if there's even something wrong with them doesn't seem like a very good idea for the moment.

He also suggested to try them with some known software and commercial DAC but, unless any of you know someone I could contact in Spain that has them, I think it's very unlikely I'll be able to do that.

I think my only remaining option is to check everything posible with the oscilloscope and hope I can find someting that will help.

Domingo.

[dave]

An oscilloscope will show you if the soundcard dac is doing what it should. Otherwise its just guesswork

[DPSS]

Thanks Dave.
I'll let you all know when I get the o-scope. I'm going to need a bit of help using it, last time I used one I was arround 15 years younger and I didn't have much experience then anyway.

Domingo.

[drlava]

one final idea before scope.. you should double check your usb sound card control panel volume levels to make sure the proper adjustments are still at the same level (max) that they were when you set the gains using max.wav.

[buffo]

It might be a bit of a drive (or ride the train), but you might want to try to get together with some of our other European members and connect them to a different controller. I don't know of anyone else in Spain, but I know we've got members in Belgium, Germany, and Italy... Maybe one of them would be willing to lend a hand.

As for one amp having slightly more gain than the other, that's not uncommon at all. But if you can't get more than 10-15 degrees out of the scanners, then that is a problem. As Dave said though - there are too many potential variables right now.

Adam