This is my channel to post videos of my electronics projects,that I think may be interesting for others as well. My projects will cover hardware, software, lab notes, and the occasional review. Its a new channel and I have lots of ideas for more videos coming up.
I hope you find it interesting. Please leave comments
Become a Patron for early access, exclusive content and more direct access.
You, sir, just came at the right time! I was working with a laser driver circuit and didn't have the probing I needed to debug a flash lamp driver and didn't want to purchase an expensive 1000x probe. I think this will likely do the job for me!
I made my probe and it works wonderfully =) I used a single 50M resistor and 10x 100pF, 3kV capacitors in parallel with it. The added capacitance in the scope side was 10nF. I tested the bandwidth with my function generator and got good behavior until 7MHz which is pretty good!! Once again, thank you sir; such a simple thing but you are helping people out there 🙏
I bought years ago 2 of those for 13e each now you can't find them at this price , they are identical I think , I don't remember if mine have 2 ICs on the inside but the shell and the rest are the same
Mükemmel teshis bende aynısı var ve neden ölçümlerin sürekli farklı çıkmasına bi anlam verememiştim ayar potlarından ayarladım ve gerçeğe yakın geldi teşekkürler çok faydalı video
This python script works just as I had hoped to control my DPS5005, great work! At first I just got timeouts, because I forgot you must change the serial speed to 19200 as shown in the first DPS video, in the menu accessed by holding down the V/^ button at powerup. Otherwise, mine was set at the factory to 9600 bps which the script wasn't configured for.
Looks like links are now disallowed, but just FYI, for "Seven Segment OCR" I found some github code from "auerswal" named "ssocr" worked OK for me back in 2013, and I see the code has been recently updated this year (2024). It works with a tight crop of one LCD display only, not a bunch of different displays. Lower resolutions worked better. Too many pixels confused the program.
Great info here, thank you! I personally had to remove the 39K resistor and replace it with an 82K. No matter what resistor I put in parallel with the 47K, it wouldn't let me get it in range for whatever reason? Maybe a slight board change? Who knows? I removed the 39K and tried various resistors with higher resistance. The 82K put me 1 Hz away from the 10 MHz signal coming from my GPSDO. This is with the 52K pot in the middle position so I have close to plus or minus 30 Hz. The SMD resistors on this board are size 0805 just in case anyone wants to buy replacement SMD resistors. Thanks again for the info TheHWcave!
Most of the less expensive DMM’s are perfectly fine for hobby electronic work but not really suitable for any power measurements. Common sense I guess. Likewise if I had cost & size constraints, I would opt for the small Uni-T with the clamp (UT-210). Small and has a surprisingly good feel. Most importantly though, like was displayed perfectly here. The best upgrade for any cheap meter is some decent probes.
Yes, very easy to buy whatever the other meter is that has the exact same brand model but is a different 2000 count meter... For simplicity with 3 terminals, I still think it is very hard to beat Aneng 8008/8009. The only thing I miss on it is the REL function. Recently I have been tempted to get a ZOYI ZT303. I believe ZOYI are the OEM to Aneng DMMs anyway. It seems to use the same DMM backend as the AN870, giving 22000 counts, but it is in a slightly smaller package.
I've noticed a seemingly identical for case and shape meter sold under a different brand name. Checked again and they are not of the same quality, this is the better one with decent electronics and display. The other one is probably fine as well for the lower price but beware of copies. I could probably buy one to take on my campervan trips. One error I've made in the past is buying big meters for the bench besides the bench top DMM. Don't, the smaller it is the better at least for me.
thank you so much.... I just bought a CA702 and was disappointed diode mode fails to light a LED. the build quality seems ok but I am a little disappointed for a 40euro meter.
Yeah, you can get better meters and I would not buy this one again. Problem is that this kind of stuff is rarely in the specs/manual and you can only find out once you have it in front of you. To that tune, I am starting a review series of some budget meters soon.
One channel at the input and one at the output, but (!!!) before you do that you need to check if ground is the same for input and output. Usually the input is but the output often is not (talking audio amps here and their speaker output), This is often the case for beefier outputs. in which case the scope cannot be grounded or you will short circuit the output. This means you have to do it in steps. Measure input voltage (nothing else connected), then measure output voltage (nothing else connected), calculate gain. Repeat for different frequencies ...
Hi HWCave, thank you for all your great content! I wonder if you could please help guide me with a firmware update for the TC66. Mine came with v1.12 but I believe we are now up to v1.18
Hi HWCave, thank you for all your great content. I wonder if you could please help guide me with a firmware update for the TC66. Mine came with v1.12 but I believe we are now up to v1.18
Was just rehabilitating a vintage Variac and had to give this a watch! A lot of the vintage ones weren't grounded at all interestingly enough. The vintage ones do use a double pole switch as well, but I'm not sure if there's much point in breaking the neutral at the same time other than maybe to prevent arcing if you are using it under a super high load maybe? I've also see where they are configured to use a switch that sets whether live voltage is applied to the very end or part of the way in so that you can choose between over voltage and mains voltage as a maximum. Assuming your varian is wired correctly, and the output was at 10VAC, how would touching it be harmful? Where I think the danger lies is if live and neutral are swapped. In that case, then yes, touching the 10VAC output' is really touching the mains voltage in reference to ground. This could happen for two reasons - if the outlet you plug it into is wired incorrectly, or if the variac has a non-polarized plug and it's plugged in the wrong way. Lastly, is there anything preventing you from applying your live to the center tap? Doing so I think would give you an output that is about double the mains voltage, though I don't really know what use you'd have for ~500V, but it could be useful with 120V sources to up convert to 240. My guess is that the downside would be that it could only handle half the current at the higher voltage
It is probably safe to touch it if its 10V but as you say, L and N could be swapped and anyway it is probably never a good idea. I don't think the wiring and isolation is designed for such high voltage that you are thinking of. I use an external isolation transformer if I need higher voltages. Much safer,
Dude, that was beautiful I almost peed myself when you addressed the negative voltage as I am working on the Elenco XP-720K kit. thank you for being thorough.
Thanks, for another great video!!! Precision printing tips = I print my DIY PCB board layouts to 100% scale, in order to proof the footprints to the actual component, itself. In learning about doing that, I discovered that inkjet printers have a common problem... Even set to 1:1 scale, they do not print true. I checked mine and, yes, it prints slightly smaller than it should. Here is my work-around... I add a 100mm line to a layer that is not active on the actual board... In KiCad, I use the Users Comments layer. I print the board with the User Comments layer set to be included. After printing, I measure the line with a ruler that I know is true. My line measures 98mm, so I adjust my printing scale to 102% This works well enough. This procedure should work correctly for meter faces, as well. HTH.
That is a good tip, thanks for sharing. I remember similar issues when using an ink jet printer. These days I am using a Samsung laser printer and find that it is quite accurate
14:15 I was able to do a quick test of this on my TF2331 this morning before heading out on a trip. With shorted inputs it read somewhere in the middle between 0 and 1 on the 0 to 10 scale of 0.1% So in the 0.006 - 0.007% area of distortion. And with a slight movement on the needle, sugesting that it's noise it's picking up. Your's looks to be at about 0.004 (not 0.04). Probably not that bad considering the old germanium transistors in this units... I tried measuring the voltage on the output, but it was all over the place. Starting at several voltages and slowly counting down into the milivolt range. Have to investigate this further when I get back to my shop later this week.
@@TheHWcave I made a mistake and measured the DC volts at the Output, that explained the strange readings I got. Must have been way to early in the morning... Anyway, when I hook up my HP3400A True RMS meter to the output, things look much better. I put the HP meter on it's 100mV range, and then do the "Set reference level" on the TF2331. With a 700Hz 2V p-p input signal from a Uni-T sig gen, I was able to dial it down to around 0.0025% THD. The controls (frequency and phase) are extremely touchy at this stage, so I'm considering replacing them with newer ones. Changing to a 10KHz signal I was able to get the THD even lower, down to around 0,0015%. I had a scope connected in parallel with the HP meter to watch the signal, and it's basically only noise left at that point. At least that's what the scope is able to pick up...
@@geirendre Very interesting. So using an external meter works fine with your unit. This means I need to go on a hunt to find the source of the excess noise in mine.
Thank you for another interesting video. Your solution for the meter scale replacement is excellent - I have filed it away for future reference! Regards, David
That square wave filtered graph would seem to be the most informative - something causing the lop-sided waveform. I wonder if it's more caps needing to be replaced, maybe even selected for some moderate matching.
I have the XDM2041 and after 2.5 years the display is starting to show. It is the same as the XDM1041. A red line runs through the screen and a part of the image remains black due to the reduction. The meter is placed in a place where no damage can occur. I've taken the display out and looked, but can't buy or find an alternative. The type number is: YYS37HV-133-A7 and the dimensions are 54.5mm x 85mm
Another option is to add an AC socket in place of the lamp socket into which a high wattage resistive load can be plugged, such as a clothes iron or a resistance heater. That allows you to test higher wattage DUT.
Thx for the video, but aint this meter like a 25 buck device, so its build to a price so how other meters to +500 to 800 dollar does it when charging like Agilent... arhh come on, be grounded.. at the end of the day.. it ain't kids that uses such a device but usually adults and you as the consumer also have a responsibility to not do stupid things that clearly ain't intended... like having a charge lead hanging loose when checking high voltage mains and even ignore the warning on screen and double dipping to counter the lockdown as come on, whats next.? you also have a responsiblelity.. when you wanna work with mains.. you need a certain skill and understanding of how things work.. just as, if you wanna work on mains voltage, then get a decent meter, not the cheapest ones form China.. use common sense.. The only item I got from Kaiweets/Habotest etc is the 35 dollar HT208D (incl. EUVAT) and that is mainly because of the inrush which were surprisingly okay both in DC & AC not least with the price in mind.
6:52 there is 6 pin tiny component on the left which is close to the edge and two other smd components Are they presoldered? I want to buy this tester but I can't solder smd component.
For Christ sake people, it's a cheap ass $10 meter and a 1Hz difference doesn't amount to squat. Here's a simpler fix - put a piece of black electrical tape over the far right digit - problem solved. 🤪
No, but I have not had any problems, using it every summer. Rather than trying (in vain) to make something 100% waterproof, I drilled a little hole at the bottom so any water that gets in can drain out.
Very pofessional. It seems like those Varta 9V ready to use rechargeable batteries are still the best 9V LSD batteries available. They only have 200mA instead of 300mA that other's have. But they self discharge at 25% per year instead of 50% per year as most other 9V LSD batteries do. It seems like 9V block batteries haven't advanced in 5-10 years. Other form factors such as AA have much lower self discharge by now. Yes I know this 9V block is 7 cells in series, while the AA batteries only have 1 cell. But 25 to 50% self discharge per year is still too high for batteries marketed as LSD. Moreover from some ~20 ANSMANN 9V LSD batteries that I bought 2 are outright duds that won't hold a charge for 2 days. And from the rest about half self discharge within 3 months. And the rest has wildly different capacities. There seems to be near zero quality control for some of those 9V batteries.
I just picked up one of these kits. I know very little about electronics but I'm wanting to learn (at 40 years old). This video series is excellent (in fact all your videos are). I didn't understand everything you talked about, but I feel I've learned a LOT more than I knew before I started. Unfortunately my kit came with the SMD components not mounted so I have a harder challenge to build mine, but this will be something fun to look forward to down the line. Thanks for posting the good content!
I have a XDM1241 (batter powered). I don't like the DCV autoranging either. I did measure the burden resistance of the DC current measurements: 50uA & 5mA = 101 ohms, 50mA & 500mA = 1.46 ohms, 5A & 10A = 0.030 ohms. I am very sure ACI uses the same shunt resistors. It's a pretty decent meter. I really enjoyed your thorough review - exceptional!
I do not have a load to measure battery capacity. So how can I use TC66 to get actual battery capacity (mAh) of power bank using TC66 but no load item to discharge the power bank. Thanks
You could use any USB device as a load, for example LED lights or indeed charging a phone/tablet but there are issues. Those loads may turn-off on their own making the results a bit unpredicatbe and not easy to repeat. Better invest in one of those very cheap USB loads on the "Internet" that consist just of a USB socket, a switch and 1 or 2 big wire-wound resistors to draw either 1A or 2A at 5V. They cost very littte and enable reproducable tests, just beware, these get very hot. Don't touch and keep well clear of anything that can burn. The 2nd fundamental problem is that measuring a power bank from its USB output will always show a lower capacity than what the battery really has. That is because the electronics in the powerbank to produce the nice and stable 5V take their "cut" and delivery only 70-90% of the battery capacity. The same problem happens when measuring charge going it. Now the USB tester will record more capacity than the battery really could store because of the inefficiency of the charging circuit. The omly way around these issues is to open the powerbank, disconnect the battery and measure it directlt, but this is an advanced operation and needs experience. Just accept that measuring "from the outside" will not give the true battery capacity but at least the capacity usable in practice.
@@TheHWcave thanks for the very complete answer as well as tips and info. I think I will take your advice and get one of those load resistors since they cost next to nothing and I could use this USB tester for other batteries etc in my house so a very small cost for alot of information i could get back. Keep up the great vids - I appreciate them.
Certainly best review I have seen on a DMM. Very articulate and to the point. I have couple of flukes and 118E. Bought this one today before watching your review. Let's see how I like it. BTW i'm a casual user, hobbyist and fix personal stuff when needed. Thanks for very soothing review. Most cause me headache...lol.
It seems the 1905a is a capable meter. How did you become so familiar with it? Have you used one before or did you need to absorb the manual for the two videos? The three push switches mounted on the back gave a very neat solution with the plate being mounted internally to the casing.
Terminal G is used in a measuring circuit with shielding from leakage currents. In this circuit, L is connected to the line, E is connected to ground, and the conductor of terminal G is wound around the insulation of the line core with several turns.
True analysis free from marketing.which is budget friendly as wel as accurate.i think zoyi zt 300ab or htc dm98 or of such similar kind. secondaly recharging batteies r creating trouble after long use brust or enlarged like ballon may damages multimeter body.if AA size has enough life then it is not good to think about rechargable battery and creat problems of charging and as u mention in ur valuable video. Thanks for vivid transparent analysis .👌
