Welcome to a new Voltlog, this will be a rather short video cause I will only be addressing one short subject regarding the Riden RD6006 ripple noise. In my review of this power supply in Voltlog #284 I did measure the output ripple but that was measured while using a transformer to power the unit.
That transformer has very little output noise so the results we obtain can be considered best case scenarios but this may vary in practice, especially if you are using the recommended switch mode power supply. The output of that power supply may not be as clean as the one from the transformer so in this video I’m going to measure the output noise with the switch mode power supply installed.
I’m using the recommended NVVV 400W 60V 6.6A rated power supply, this is what RuiDeng officially recommends to use with their power supply kit. In Voltlog 284 part 3 I took a look inside this power supply so I will link that video on screen if you want to check it out.
Welcome to a new Voltlog, if you’ve been watching the channel for a while you might know I’m a fan of the gopher power supply units, I think they are great value for money, they’re simple and they have good specs, in fact I reviewed their latest revision in Voltlog #255 and it had very low noise at the output, even though it is a switch mode power supply. They’re pretty compact, they don’t take up much space on the bench so what’s there not to like about these?
But in recent years there’s been another company which has slowly built-up a name among hobbyists due to their really low priced power supply modules, the name of the company is RuiDeng and they’ve been selling these compact switch mode power supply modules for $20 to $30 for years. They were not great specs, the quality was not great, you needed an external power supply unit but they had a bunch of functionality built into that color TFT display and they were cheap so everyone gave them a try
Now RuiDeng has developed and released a new model RD6006 which resembles a real bench power supply. It has a bigger front panel and it comes with a separate enclosure and power supply unit which are optional.
Welcome to a new Voltlog, it’s November and that means the biggest shopping event happening in Asia is coming up, I’m talking about the 11th of november. There are some numbers published for last years event and it seems they registered more than 30 billion in 24 hours in sales, yes you heard right, billions. So it’s a very big event with nice discounts and opportunities for makers like us to get some new gear. That’s why I prepared this video which will be published 1-2 days before the event so you can get some ideas of stuff that you could purchase. I assembled a list, these are products that I’ve tested and used myself which I think are good value for money and a nice addition to any hobbyist lab.
Welcome to a new Voltlog, those who have been with me since the beginning of this channel, may know the first video I ever released, Voltlog #1 was a review of a switch mode bench power supply from Gopher Technology. It was the CPS-3205C and it was a great little unit, it has served me well over the years and I still have it.
At that time I complained about the fact that the unit has the output jacks on the back which is not really convenient for bench use. There were also other issues mentioned while measuring the performance of the power supply, I will link that video on screen if you want to watch it but the video, audio and editing quality are lower than what you’re seeing today.
Gophert made some improvements to the original design and have now released a newer version of that power supply, it has a new model number it’s NPS-1601 but it’s the same range of 0-32V and 0-5A. There are other models with different ranges but this is what would correspond to the CPS3205 I reviewed years ago.
They have made a bunch of changes on the front panel, the most important one is they moved the output jacks to the front panel so now it’s easier to connect the output of this power supply but they are still not standard spacing so you can’t connect one of these adapters with banana jacks. They have also redesigned the front panel completely, they are still using 7 segment displays but now they also have a wattage display which can be switched on temporarily in place of the amps display, you press the watts button and it will show watts measurement for about 3 seconds before reverting to amps display.
The switch for A/V adjustment is now tactile instead of a sliding switch but the rest has stayed the same. I like this redesigned front panel I just wished they used a lighter color for the text, because for example there are some markings which are barely visible next to the LEDs.
Here is a set of pictures I captured during the teardown:
A while ago I showed this power supply kit, which I ordered from ebay. It was being advertised as an LM317 0-15V 0-5A adjustable power supply kit and it looked promising. Upon receiving the kit and taking a closer look theres 2 thing to mention, one the power supply is not based on the LM317 but on the TL431, they used TL431s instead of op-amps in this power supply design and two there isn’t much documentation about this power supply.
The components used are low quality but that is to be expected from these cheap kits coming from china so no surprises there. If you would like to use some better quality parts I would suggest replacing the electrolytic’s and the TL431s with ones sourced from known sources. Also a nice upgrade would be to use some 10 turn pots instead of the supplied ones to get some finer adjustment. But I just used the originally supplied parts to see what kind of results we get with those.
Here is a screenshot with the signal measured right on the bulk filtering capacitor (4700uF). Looks like this might be the cause of the 100Hz oscillation we we’re seeing on the output.
Here is a screenshot with the current overshoot. The power supply was set for CC 50mA and I suddenly shorted the output through a 1ohm resistor. The scope probe was placed across the resistor leads on the low side ( 1mV = 1mA ). As we can see we have a huge spike of current that could potentially fry an LED connected on this power supply. However the spike lasts less than 1mS which is good and I have observed similar behavior on my HP E3611A analog bench power supply.
Here is also a screenshot with the power supply regulating the current at 50mA in CC mode. This doesn’t look right at all.
Last InTheMail video was published almost two months ago so I think you will appreciate this one where I got some interesting stuff from the usual Chinese sources.
Links for all the items shown in this video below:
So I guess a gadget like this is worth 10$ because you could replace that linear breadboard power supply with a more efficient one, which will give you voltage and current display as well as adjustable output.
Here are some images I took during the teardown of the mini power supply:
In this video I am repairing a power supply board from a Samsung TV. The part number for the power supply board is MK32P5T (BN44-00213A). The TV was showing the stand-by led but refused to turn on. It turns out this was a common problem with a simple fix.
Here are links to some of the tools used in this video:
Welcome to another Voltlog, today we’ll be taking a look at what I’ve been receiving in the mail recently. As much as you guys like watching this stuff, I also like getting all these electronic modules from China. I find it interesting every time I get my hands on a new circuit.
As always I appreciate feedback and discussions in the comments section below, please let me know what you think and don’t forget to like the video, that is always a clear indication of what kind of content you guys like seeing.
Here are links to all the items shown in this video:
Today we are taking a look at this old network equipment, it’s a Nokia IP330 Firewall. This router / firewall was released probably in 2000 or something similar, I couldn’t find any exact info on the release date but we can safely assume it’s at least 15 years old
Don’t forget to like & comment, that helps the channel grow.
