got a package in the mail from Shih Wei Chieh


first go


find out what's up with the Y axis galvo. it gets very hot when on and doesnt move.


Shih notes, similar to ldgraphy

the scanner is PT-A40

manual for PT-A40

what's inside?

AlliExp stroe (not he one sent)-
pro ThorLAB -

Basic Tuning
Basic adjustments
The driver board comes already pre adjusted for 3 projection angle and needs to be set up for
the galvo only in small areas. Every galvo is different, so 3 of them adjustments are needed. For
this, the ILDA test pattern is used ,also a setup of the galvos in XY with a laser . If you need to
tune the driver faster to smaller angles, follow the procedure below . Also if the driver is totally
deadjusted , this will be the procedure to retune it :

  • Size, Servo-Gain, Damping und HF-Damping are adjusted counter clockwise to their left zero position. Now turn LFD 5 full rounds clockwise to right.
  • Connect computer with ILDA test pattern, run it at approx. 20kpps.
  • Power on the amplifiers.
  • Slowly open the servo gain (clockwise). The mirror of the galvo should move now to its middle position. If yes, turn two rounds clockwise.
  • Slowly open the size until you see the galvo moving.
  • Increase servo gain until you see overshoots. Correct it with LFD.
  • Decrease undershoots by opening the HFD pot slightly clockwise. Remove gain/LFD procedure and correct with HFD, until you the picture looks satisfying. Carefully fine tune the driver. The better your fine tuning is, the faster is the scanspeed.
  • Increase speed of test patterns and readjust for optimized picture



needs 3 channels of audio to control X/Y/PULSE
jack got me this to test

“has 1 stereo out and 2 mono”

maybe axoloti if i had it.