Recent content by Scotoma

I was just wondering if anyone has ever seen this issue. Sometimes after turning on my scanner or after having my scanner on for a while, the soundcard dac will all of a sudden start outputting the max number of volts (set to 5) on just the red channel, even with the volume of max.wav set to 0...

So oddly enough, connecting the galvo modulation grounds to the same place as the laser modulation grounds got rid of the "waving". Upon simply disconnecting the galvo modulation ground wires, the "waves" were still present. It was only when I plugged them in to pin 18 with the red laser "-"...

Thank you for all the input. I won't have access to the scanner again until Friday, but I'm 95% sure that the problem is the connection of the galvo signal input to the ground pin 25. First of all, this pin is not connected to the common ground like the pins 18, 19, and 20 (for the lasers)...

Alright, it sounds like it might be the wiring, so I'll take a look at that and let you know how it goes. Actually, it makes sense that this might be the problem, since I'm kind of confused about what is actually supposed to be grounded where. All my lasers have + and - modulation wires that...

I have a set of PT-30K galvos that still need to be tuned but that are producing decent, recognizable images using a soundcard DAC and HE Laserscan 5. The problem I am having is that all the images (test patterns, for example) look like they are being modulated by a sine wave at about 2 Hz. In...

So, just to make sure, when deciding on the current for these drivers, we should take into account a 40 mA (rhd) to 152 mA (tsteele) ringing? In other words, the output might go as high as 20-76mA above what it's set to? Thanks for troubleshooting that startup spike away tsteele :beer:

Oh, I see. I was wrong then, the frequency is 1 / (3.5*.0000025) = 114285, or 114 kHz as previously stated. Sorry for adding confusion to the thread.

The following is incorrect because the divisions are 2.5 us, not the whole picture... I hope that helps. Thank you for designing this affordable driver. Hopefully this ripple will turn out to be nothing. If not, hopefully the fix will be easy. Cheers :beer:

Re: FS (offers): LaserBee IX 2100mW + DIY case Payment sent, many thanks Arayan

Beautiful, many thanks ElektroFreak

This question probably has a very simple answer and will most assuredly betray my extreme ignorance, but I can't seem to find the answer anywhere. Does anyone know how to mount the scanheads from pt-30k scanners into the mount? Does the orientation (angle) even matter, or is the angle offset...

So it sounds like there are two potential explanations for the excessive current through the diode. One is that the flexmod temporarily lost the ability to regulate current while the circuit was shorted and that upon reconnection, it sent a current spike to the diode before recovering. The...

I would definitely be willing to give it a shot, though this thing looks really fried, and I might have damaged it further taking it out of the aixiz. Maybe I'll see if JSLE wants to give it a try. Thanks for the suggestion.

Thanks for the reply Things. I connected the driver up to a dummy load, and it seems to be supplying the correct amount of current at both 0V and 5V modulation, so at least it wasn't a $140 mistake. I won't be leaving connections un-insulated again.

So I just learned an expensive lesson about keeping the connections between drivers and diodes solid. I was using non-insulated, crimped-on terminal connectors for the connection from my flexmod to a mitsubishi 500mw ML501P73 diode. The exposed metal from the connectors touched my aluminum...