I'm glad this video's finished
Added 2024-09-19 04:07:20 +0000 UTCIt's a good video about a very interesting product, but the circuitry was so complex and weird that it took me much longer than usual to reverse engineer it.
That said, it had lots of very novel surprises and also two hidden features I didn't know about until I found their circuitry and went hunting for them.
Comments
For the record, I absolutely appreciate these longer, more complex videos. I always end up feeling like I know nothing about electronics when I watch them, though - my understanding of analog electronics is just enough that I understand what you're saying when you say it, but I wouldn't have been able to work it out on my own. I'm sure the more I watch, the more I'll understand!
Circuitmike
2025-03-11 16:48:20 +0000 UTCVery worthwhile Clive. I wonder if the default (starting) voltage shouldn't be 18V - if you don't know how to change to 300V you probably shouldn't be messing. Also, 18V at the wrong polarity might not kill a lower-voltage LED
Gordo
2024-11-10 16:49:42 +0000 UTC... Try looking for "Wang Yatian GD-9" ... Claims to be 9th generation of this device and not a counterfeit ... "After being identified as a light bar, the primary current is 20MA, the secondary current is 48MA after seven seconds, and the three-stage current is 75MA after seven seconds".
L. Brait
2024-09-28 09:12:52 +0000 UTCI'v just sent for some servos to try out. They look the same as ones costing quite a bit more elsewhere so I'm curious to nsee if they are as good.
Mike Hughes
2024-09-23 16:47:26 +0000 UTCThis is lab equipment, so users should assess risks professionaly .
adorfer
2024-09-21 01:50:58 +0000 UTCI will watch the video at least 4 times from different devices. Since it took you so long to get the schematics down, and I really appreciate that.
adorfer
2024-09-21 01:48:53 +0000 UTCThere is certainly a time factor. The IEC 60479 curves - which are somewhat empirical - are finding their way into various standards and they help people think about symptoms. I know you can't buy an insulation tester for £10 but that's what I'd want. 2mA is half the perceived brightness of 20mA.
Mike Page
2024-09-20 21:19:46 +0000 UTCThe high DC voltage is a tricky issue. It's needed to test modern LED arrays, but does pose a slight hazard. Less so than AC which continuously stimulates muscles and locks your hands on, but still a risk of an initial high current pulse. The soft ramp may help there. Keep in mind that the medical treatment for excessive perspiration (iontophoresis) does often involve passing 10's of mA DC current hand to hand.
Big Clive
2024-09-20 19:44:39 +0000 UTCOne of the Ali listing I was looking at does mention the mode select, kinda. "Short circuit the stylus for plus or minus three seconds to switch between high and low voltage."
Mark Arnold
2024-09-20 11:46:50 +0000 UTCGood to see a decent leadset with GS38 prods. Just as well because the guts are unsafe, delivering more than the Single Fault limit of 140V and 15mA. There are also "foreseeable misuse" issues. Unlike an insulation tester, it does not safely discharge the load. This could leave large capacitances charged. And even though isolated, if used to test a grounded LED, the other prod becomes hazardous. So: nice and cheap with nice leads but use with great care!
Mike Page
2024-09-20 11:38:51 +0000 UTCLoads of genuine good items on AliExpress if you spend time looking. Take the Web-888 SDR radio, for £200 delivered you get a very good web SDR from the actual manufacturer. Some other devices for not very much include several active antennas, filtered RF amplifiers, and multi-couplier antenna splitters. All tested, well built and in heavy duty use, and all operating in designed spec. I know these are exceptional, there is a lot of crap there too but not everything is bad.
Dennis
2024-09-19 21:06:06 +0000 UTCThe leads short circuit gate. FU1N60A
Jaden Huibregtse
2024-09-19 17:20:14 +0000 UTCClive, fantastic video, well done. More like this please! A nice follow up may be to show how to swap the resistors to calibrate the voltage display to make it a little more accurate?? Thank you K. GetCarterCarPark.
Keith W
2024-09-19 13:06:16 +0000 UTCProves that there is some good tech on Ali Express, for not much money.
Mike Hughes
2024-09-19 09:28:33 +0000 UTCThank you very much for doing all the work of reverse engineering the device. I can see it would have taken a lot of time. As Zac already said: Great work!
Frank
2024-09-19 07:48:39 +0000 UTCThat was a very impressive bit of reverse engineering! I love that you can explain to me how that functions when I’m not in the trade. It’s one of the major reasons I’m here. I learn so much from you and it’s always entertaining. Thank you for the work you put in, it’s very much appreciated.
Dave Roberts
2024-09-19 07:46:32 +0000 UTCNice to see clever use of existing chip technology for other purposes. Thanks!
Mark Warburton
2024-09-19 05:01:32 +0000 UTCOne of my favorites
Geoffrey Waldo
2024-09-19 04:53:23 +0000 UTCGreat work. Love the complexity.
Zac
2024-09-19 04:34:49 +0000 UTC
