how to wire galvo driver signal to ILDA with only X gnd and Y?

[laserjohnn]

i have a small 10K scanner set from china which has a signal connector with 3 pins
the 3 pins are X, GND, Y
the signal required that manufacturer told is "Max ±10V input singal"

now i have my ilda connector which has X+ (pin 1) X- (pin 14) Y+ (pin 2) Y- (pin 15) and GND (pin 25)

how would i wire this correctly? i use a pangolin FB3-QS. isnt this outputting +5v to -5v?

[JohnYayas]

Use X+ Y+ and GND.

[laserjohnn]

would'nt this give only half angle when using it with a FB3-QS as it only outputs 5v?

[JohnYayas]

would'nt this give only half angle when using it with a FB3-QS as it only outputs 5v?

Yes. But, you have to work with what you have. I'd contact Pangolin AND your galvo manufacturer to see what they recommend in that case.

[buffo]

Your only other alternative would be to build a differential receiver front-end for that set of scanners. All you need is two op amps and some resistors. (You already have a +/- power supply for the scanners which can also power the op amps. Suggest using something like a TL-082.) This would give you back the full signal deflection.

Note that your statement about the FB3 "only putting out 5 volts" is misleading: it outputs +/- 5 volts, just like every other controller that follows the ILDA spec. The ILDA spec for X and Y signalling is +/- 5V *differential*, which means if X+ is at +5V and X- is at -5V, that yields a +10 net signal. Now reverse those numbers, and you get a -10V net signal. The total swing between them is 20 volts, even though the voltage on any one pin (X+ or X-) never goes above +5 volts or below -5 volts.

The issue is that the manufacturer of that cheap chinese galvo set did not add a simple $0.20 chip to handle the differential-to-single-ended conversion on the input stage of the amp. So your choices are to add the op amps yourself, or live with half the max scan angle by only using X+, Y+, and GND.

Adam

[laserjohnn]

i recently came up with this project again and was wondering if you would have a schematic of this?
i lack the skills to design this myself but i guess this would be a really simple schematic.

i do have +15V GND and -15V from the PSU
the signal is +5v to -5V for X scanner and +5v to -5V for Y scanner
with this option the signal would become +10V to 0V for X and +10V to 0V for Y
so then it would be possible to connect it to 3 pins (+X, GND and +Y)

i do have some solder skills and breadboards for testing, hope anyone could help me with the schematic

[mixedgas]

The ILDA standards of old are a sticky on here, see page 14-15-16 of attached PDF for explanations and line receiver / transmitter schematics:

Power supply bypass and filter capacitors for the opamps are implied, but not shown. Usually I install clamping Zener diodes on the outputs of these circuits to prevent problems.

Otherwise the sticky with three PDFs of the old recommendations are a sticky at the top of Laser Displays, Shows and Scanning section of the forum.

https://photonlexicon.com/forums/sho...ILDA-STANDARDS


Steve

[laserjohnn]

Thanks for the schematic, i am rather new to electronics so i made a little drawing, would this be the correct wiring?
is it also correct to wire gnd to pin 25?
and not exactly sure where i should put resistors and what value

[mixedgas]

Thanks for the schematic, i am rather new to electronics so i made a little drawing, would this be the correct wiring?
is it also correct to wire gnd to pin 25?
and not exactly sure where i should put resistors and what value

No, not without the resistors
Steve

drawing coming soon..

Steve

[mixedgas]

Drawing came Late...

See attached,,,,
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Yes, I'm having a little fun with my response... But for beginners in electronics, its sort of how you think at the start.
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There is a E-book for Kindle etc of Bill Benner's book for like 99 cents... Suggest you buy it...

LASER SCANNERS: Technologies and Applications: How they work, and how they can work for your product: Benner Jr., William R.: 9780692747773: Amazon.com: Books

Mr. Benner is Mr. Pangolin...


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May I suggest the following light reading titles:

abebooks.com is a great asset for electronics texts:
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Electronics Circuits for the Evil Genus by David Clutcher
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The Art of Electronics by Horrowitz and Hill (2nd Edition)
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The freebie that is very good, curtesy of the Navy

Navy NEETS modules 1-24

https://schems.com/NEETS/
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Takes a while to go through this, Elliot Labs, and your there for the style and technique, but laser show signals are Audio down to DC for the most part:

https://sound-au.com/

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Freeware 2D cad for schematics:

http://www.cadstd.com/

Most people end up registering it anyways for the extra tools..
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Enjoy....

Steve

Steve