Has anyone tried these galvos?

[carmangary]

what is a catweasel and xt wide style? Nevermind... I looked around on the internets and found info about them.

[carmangary]

My chinese 30K galvos arrive today. woohoo! Is everyone excited about the upcoming review? hehe.

[buffo]

Carmangary;

Actually, yeah, I am looking forward to your review. I'm actually about to undertake another review myself, and it's also going to be a galvo review. I'd be interested in comparing notes after it's done. (I won't get them for about another week or two though.)

Adam

[carmangary]

I received my chinese 30k galvos and tried them out today. I already had a chinse 15K scanner set and they were really quiet. The 30K set is definitely louder. Do all galvos make noise?

They are definitely a lot faster than the 15K set but I think they need tuning. Also, their is some noise from somewhere because I have some ripple in the lines. My next thing is to change the piece of junk dac-to-amp cable to a shielded on and then to try to tune them.

One thing I found is that my printer port DAC really shows its weakness when going at 30K. I think it is definitely time to move on to something else.

[buffo]

In my experience, galvos only make noise when you're overdriving them. I used to get it every once in a while with my DT-40's when I was playing around with my Alphalite's abstract generator. It can make some cool patterns, but it can also smoke a set of galvos if you're not careful. (Pangolin's abstract generator is much more galvo-friendly, though if you're really determined (or really stupid) you can still push the galvos too far.)

Are we talking about a slight buzzing sound or a high-pitched screeching sound? The former is OK, the latter is bad!

Adam

[carmangary]

The galvos squeal and clack. Sounds awful. Then I took one out of the holder block and it got quiet. Stuck it back in and it got loud again. All I have to do is touch them to the holder block and they get loud. It's crazy!

[allthatwhichis]

I'm gonna say that is bad, but make an audio clip and take a poll.

[Pangolin]

It's funny... In reading the manual, I don't know if these guys are the original manufacturers, or merely resellers...

The 10K variants are made by a company called "LaTu" (pronounced Lay Too). I have seen them installed in many Chinese-manufactured projectors. Also I think someone on this forum sells the 10K variants.

In general, scanners don't make noise. At least, not while projecting most imagery... What Buffo said was correct. If you put high RMS demands on them, such as raster or abstract imagery with a lot of squarewave or high frequency sinewave content, you will hear them. But never things like "cracking"...

Will you be at SELEM? If so, I am sure everyone would love to see (and hear) them

Best regards,

William Benner

[buffo]

Hi Bill!

I've been trying to talk Carmangary into attending SELEM for about a week now! Saddly, he said he had a previous engagement. (But I'm not giving up yet!)

But yeah, it would have been fun to see those galvos in action at SELEM. (Though from the description so far, it appears we might need earplugs!)

Adam

[carmangary]

OK, my galvos are much better now. When they were shipped to me they were very badly tuned. Here is a list of issues that I had and how they were overcome:

(1) The scan angle was only 10 degrees at +/- 5vdc. I didn't know I needed to connect the (-) differential connector on the scan amps to gnd. Once I did this the scan angle doubled. I can double it again by using adjusting the input on my scan amp or by using a differential signal DAC. So, this issue is solved.

(2) The galvos made a LOT of audible noise and produced visible oscillations in some ILDA files. It turned out that the scan amps were VERY badly tuned. Once I tuned them using the procedure on the LaserFX website the galvos became very quiet and the oscillations went away. Another problem solved.

Currently, I have no more issues with the galvos. They can easily do 30K pps. It is amazing how much more stuff I can do than with my 15K set.

The company I purchased these from have been very helpful. One of the support people in China was on MSN messenger with me for an hour one night helping me to solve my issues. They actually initiated it when they saw that I had posted an issue on this website! So, they are very proactive in helping their customer.

In fact, I LIKE THE GALVOS SO MUCH THAT I JUST BOUGHT 10 MORE SETS!!! So, if anyone wants to buy a set from me please send me an email. Otherwise, you will see them on Ebay.