Hammer time...

Just a quick one. Today is Father's Day and this was the gift from my boy.

Love it!

More soon, no doubt....

D.

Nitecore D4 charger fault (fixed)

I bought this Nitecore D4 charger from Fasttech nearly four years ago. I use it for charging my collection of Samsung 18650 batteries. I use it everyday.

In the past few days though my charger has been misbehaving. It doesn't appear to have been charging properly, especially when loaded with cells. The screen was also flickering and the information on the display was random nonsense. Oh dear...

Naturally, I had to open it up. This is the charger with the back removed:

Nothing out of place there, although I note some heat damage around the diode #10 (on the left of the picture). I thought I'd better lift the PCB out. Since I wasn't sure whether I could lift it out with the battery holders attached, I desoldered the four springs and earth wires, and decoupled them. I then removed the three screws from the bottom edge of the board and gently teased the board out. On the way, and as soon as I could get my fingers in the gap, I disconnected the power for the screen LED. This is what I saw next:

Yep, a faulty capacitor on the power supply side. I decided (and hoped) that that was likely to be the cause of the problem. I desoldered the faulty cap. It's a 1000uf 16v. I cannot tell what brand it is:

I had a look through my box of electronic goodies and found this, which I think is a Panasonic:

So I soldered it in....

And then I re-assembled. This was a bit of a faff, really. The LED screen sits in a plastic holder. The plastic holder sits loose in the case but if it's not in exactly the right place, the screen display will not work. I found this out only after my first attempt at reassembly. Indeed, getting the screen in the right place so that it would work took longer than the actual repair. Anyway, here it is back together. I've resoldered the springs and earth wires:

And here is my Nitecore  D4 working well again:

Happy days!

Here's a link to Fasttech in case you want to buy one: Nitecore.

More soon, no doubt....



D

ESP DVR-EZ - "no HDD" error

A friend asked me to take a look at this DVR which she has in her shop and which is supposed to record the images from four cameras that are dotted about the place. The problem was that it wasn't recording anything. Once I'd hooked it up to a monitor, I could see a message on the screen - "no HDD". Since there was no suggestion that the HDD had been removed, I disconnected all the cables and opened the DVR up. There was indeed a HDD in there but rather than wondering whether there was a fault with that, I could immediately see blown capacitors on the power supply for the HDD. Here are some photos of the DVR and internals:

And here are the two blown capacitors:

The values are 1000uf 16v. The smaller capacitors (470uf 25v) situated nearby were fine. So, I replaced the faulty caps with some new ones from CPC. Here they are:

Before reassembling everything I also checked the state of the HDD. It worked fine despite its age, although to test it at all I had to dig out an old IDE to USB connector. Yes, remember IDE HDDs?

I'll update this post once I've been able to check whether the new caps have resolved the issue. And for my own benefit, here is the relevant user manual for the DVR.

More soon, no doubt....


D