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[JimKnopf]

@Mr.B @richnormand

It cuts through 1 mm plywood like butter. 5 mm thick wooden strips can be cut cleanly with just a few strokes and without much pressure. It's incredibly easy.

It gets hot. When you pull it along a ruler, it squeaks quite a bit. I was able to cut a hole in the plastic cap of a water bottle very easily, without any effort. I think it works with ultrasound. I have a surface microphone. Maybe I can use it to determine the frequency. I'll test it out. Does anyone have any tips on how I can determine the frequency of a cutting tool like this?

[shapirus]

Does anyone have any tips on how I can determine the frequency of a cutting tool like this?

Hmmm... Connect a ceramic capacitor to a battery (maybe in series with a resistor), hook it up to an oscilloscope probe, then touch the vibrating surface?

It's just a crazy idea. I don't know if it's going to pick anything up at all, but hey, if it does, it'll be fun.

[thm_w]

Does anyone have any tips on how I can determine the frequency of a cutting tool like this?

Hmmm... Connect a ceramic capacitor to a battery (maybe in series with a resistor), hook it up to an oscilloscope probe, then touch the vibrating surface?

It's just a crazy idea. I don't know if it's going to pick anything up at all, but hey, if it does, it'll be fun.

Possibly relevant video, though at much lower frequency: youtube.com/watch?v=uU6VbJCKh1M
I think its worth trying.

[dobsonr741]

Bought the "USB 100K-10GHZ RF Power Meter V5.0" power meter on Ali. Planning to load the SCPI firmware alternative from https://github.com/iamaiy/usb_powermeter_firmware

[JimKnopf]

@thm_w Interesting Video. Chatgpt suggested using a piezo element + oscilloscope as easiest solution.
Or if available, Laser-Doppler-Vibrometer (LDV) or Laserpointer + Photodiode (Low-tech-Vibrometer).

I will see if i have a piezo element in my e-waste box. From my last project https://www.eevblog.com/forum/testgear/is-the-de-5000-software-useful/msg6095385/#msg6095385, the selfmade IR Sensor for DER EE DE-5000 i have some spare  L-53P3C photodiodes. And from my last years project (seen at Les's Lab on YT) the Pi-Spectrometer and Ulbricht-Sphere, i have a handfull of low power lasers laying around. I will test both versions.

[JimKnopf]

Follow up to my Jakemy JM-10 purchase.

@thm_w I couldn't get the laser / l-53p3c solution to work but the Buzzer works great.

I first taped the buzzer to the blade. I measure around 35 kHz. I removed the buzzer and just touched the surface with the blade. I measure 39,7 kHz. nearly 40 kHz.

[Red Squirrel]

Been meaning to get into STM32, so bought the programmer and a few STM32G07 chips to start with. My end goal is to build PoE based products for my own use. (home automation/monitoring), and maybe marketability.  Already got the Ethernet Phy and the POE chips on hand. For now will do just straight STM32 just to get familiar with the toolchain then start playing with the Ethernet stuff.

[jonovid]

rarely this happens . a crap delivery! 
this is meant to be 4 x 12v 150mW solar panels. only 2 of then are functional.

[richnormand]

Got tired of fishing the right meter or probe on deep shelves below the bench. Got Costco kitchen organizers on sale.
Top shelve will get done too