Voltlog #71 – Electronic Touch Musical Keyboard Kit

A while ago I saw this touch musical keyboard kit on banggood and it seemed interesting enough to order one. It turns out the kit is using a single atmega8 to do all the touch sensing (8 ch) and play the tunes accordingly. Although not very useful for me it sure was fun to assemble and play with.

Voltlog #69 – LM317 Kit Assembly Fail

Sometimes, when I have some spare time I like assembling these cheap kits coming from China. Today I am assembling an LM317 adjustable power supply kit complete with voltmeter. Unfortunately they sent me a wrong resistor value so the kit didn’t work as expected but I was able to fix it in the end.

Voltlog #67 – Precision Current Reference Using REF200

A while ago I watched a video from Scullcom Hobby Electronics channel where he build a precision current source, a very simple but accurate one. If you don’t know this channel I encourage you to subscribe to it, it has allot of nice videos on lab equipment either building DIY versions or reviewing existing ones. Each video has nice drawings and the guy clearly knows what he is talking about so a great resource for learning.

I don’t have any current source in my lab, and these are useful for testing multimeters for example. I was looking on ebay for a current source but I wasn’t able to find an affordable one so I’ve decided to build one using the project information from that video and I will link the video in the description below, it’s nice to watch it has lots of interesting explanations so I won’t repeat them in this video, I will mostly focus on showing you how I build and improved my current source.

Voltlog #64 – DIY Adjustable Power Supply With Enclosure

Today I’m going to be building a complete DIY analog bench power supply. The actual analog power supply kit (0-30V 0-3A) that I’m going to be using, is this one, it was shown and assembled in voltlog #8. Besides that I’m going to be using this plastic enclosure which I think is quite nice and perfect for such a project, this one can also be found on banggood and there will be links in the description for all the items used in this build.

Voltlog #62 – Rigol DS1054Z Fan Replacement

Everybody knows this is a great scope for the money but as usual test equipment doesn’t use the best solutions in terms of cooling fans and associated hardware. They care mostly about keeping the unit cool and not about the noise the unit makes because usually these are used in environments where multiple equipment is run at the same time, the noise level is already high so it doesn’t matter much if a small 50mm fan is adding noise.

But it’s a totally different story for us hobbyists that are using these pieces of test equipment indoor, in our homes. We usually want units with passive cooling or with silent fans.

Voltlog #54 – BQ24650 MPPT Charging Module

In this video I am taking a look at this compact BQ24650 Charging MPPT Module made by YZX Studio in China. You can use this module to improve the efficiency of your solar system while charging your battery.