AliExpress diodes

I ordered a bunch of SMD diodes from AliExpress (nine different types), and nine packages arrived, but they weren’t labeled. I tested everything to infer what I got, and they didn’t ship me what I ordered. My notes are here and the video of me doing all this is here.

I kept a note of the seller and will try to not order from them again. In the mean time I think I have filed the components that did arrive in the correct drawer.

Below are two happy snaps from this project. I guess on the bright side I got some practice doing SMD soldering and using my signal generator and my scope.

Oh, and I added a new item to my debugging notes, viz “is it plugged into the right socket?” (I had my output cable on the signal generator plugged into the wrong BNC connector on the device, that took some figuring out…)

John's test rig

John's test rig, labeled

Switching diodes and rectifying diodes

I had an envelope full of SMD diodes arrive today. Three different types in three different sizes, so nine bundles. Unlabeled!

I’m not sure what they were thinking at the shop. I got them from here.

I managed to figure out that the ones marked ‘S4’ were the Schottky diodes (1N5819WS). I think the ones labeled ‘T4’ are the switching diodes (1N4148WS) and the ones labeled ‘T7’ and ‘A7’ are the rectifying diodes (1N4007), but I’m not sure of that yet.

I asked ChatGPT for help and it explained how I can devise a test circuit, so that’s on my TODO list for tomorrow.

Op amp tester

I was watching How To TEST OP AMPS Using A Multimeter vs Op-Amp Tester Project Single Dual and I learned about this Operational Amplifier OP AMP Tester For Single Dual OPAMP TL071 TL072 TL081 TL082 Single/Dual Op Amp Test Board.

I have to cool it on the spending for a little while, but I’ve made a note of this on my shopping list.

Fluke VoltAlert

I was watching this old EEVBlog video: EEVblog #168 – How To Set Up An Electronics Lab and Dave recommended a Fluke VoltAlert. I discovered there are various versions, such as the 1AC and 2AC, and those alternatives are explained here: Best Non-Contact Voltage Tester.

The Fluke 1AC II Non-Contact Voltage Tester looked like a pretty good one for my purposes and I found one on eBay for AUD$35.40 so I hit the buy button.

Electronic load cables

Well I figured out how to use my new my ZKE Tech EBD-A20H Battery Tester and Electronic Load. This video was really helpful: ZKETECH EBD-A20H first look . Also I managed to find the software mentioned in the comments for that video:

The reason I had trouble configuring this electronic load is that I thought the “cutoff voltage” was a maximum setting, but in fact it means cutoff if the voltage drops below this value. That makes sense of course, especially as the main use case for this device is testing batteries. Once the voltage drops below a certain level the battery is dead and you can stop testing.

The trick with the wiring is that you can just hook the voltage and current terminals up to the battery / power supply terminals. I think the idea is that you can put the voltage and current terminals in different parts of a circuit, but I don’t really understand that, and for simple battery or power supply testing it seems you can just connect them together.

There are two modes available: Constant Current (CC) and Constant Power (CP). I have managed to get the software working and connected so that should mean I can put this up the back of my bench and control it remotely, which will be handy.

My next video will be me making a cable to fix this mess. Once I have that cable I will make a video demoing the EBD-A20H.

The cabling for the electronic load

In The Lab With Jay Jay – July 28, 2023 – Testing Riden RD6006 with 19.5V power supply

This post is part of my video blog: In The Lab With Jay Jay.

Today I confirmed I can successfully power my Riden RD6006 power supply with this 19.5V AC adapter I picked up from Amazon. Big thanks to my mate Rick over on the EEVBlog forum for his help with this one.

In this video I use a 100W 6Ω resistor to test my Riden RD6006 power supply at various voltages from 1V to 18V up to a maximum power of 54W.

I should note that in this video I tried to draw 54W of power from the power supply, but the power supply is only rated up to 45W so I probably shouldn’t have done that, and won’t have any reason to ever do that again, I was just testing the maximum. So maybe don’t do that at home. :)

Watching temperature on ‘charm’

Note to self: run these commands to watch NVMe, GPU, and CPU temperatures on ‘charm‘:

watch sudo sensors
watch sudo nvme smart-log /dev/nvme0
watch sudo nvme smart-log /dev/nvme1
watch sudo nvme smart-log /dev/nvme2
watch sudo nvme smart-log /dev/nvme3

These sensors were enabled with:

sudo apt install nvme-cli
sudo apt install lm-sensors
sudo sensors-detect