Typically, a lab power supply can only operate within a single quadrant. Take a positive voltage power supply for example, it can only output or source current. If any attempt is made trying to sink current into the power supply by connecting a voltage source with a higher voltage than the output voltage of the power supply, the power supply would lose regulation since it cannot sink any current and thus is unable to bring down and regulate the voltage at its output terminals.
The Agilent 66312A dynamic measurement DC source however is a two-quadrant power supply, it not only can source up to 2A of current between 0 and 20V, but also can sink up to 1.2A or 60% of its rated output current as well. Although lacking some key functionality of a source measure unit (SMU), Agilent 66312A can nevertheless be used in similar situations where both current sourcing and sinking capabilities are needed.
Russell Graves did teardown of a Craftsman 19.2V DieHard battery and a Ridgid 12V battery:
It’s time for more tool battery teardowns! This week, I’ve got a Craftsman 19.2V DieHard battery, and a cute little Ridgid 12V battery. They’re both lithium, and I’m going to dig into both of them, because that’s what I do with old batteries I pick up out of junk bins.
If you’re bored of tool battery teardowns, you could always send me more interesting things to mess with! I enjoy poking around tool batteries, and a lot of the ones I pull apart are “new to the internet” in that they haven’t had a detailed teardown before. It’s always interesting to see how different companies approach much the same problem.
Opening the module reveals a series of microwave PCB components and several active devices. A complete analysis of the module is presented. The unit is then measured and the impact of antenna impedance and power supply voltage on the output frequency is measured. The phase noise of the output signal is also measured. Using a series of servo motors, the radiation pattern of the antenna array in both azimuth and elevation is also presented.
IRIG time code generators (not to be confused with the ones used in video and film industry) are often used for clock synchronization among various connected equipment and is commonly used in power generation and distribution industry as well as in the military. In this blog post we will take a look inside a Datum 9300 time code generator from the late 80’s. A video detailing the teardown is linked towards the end of the post.
Specification wise, the adapter is rated to provide 2.1A for its USB output. I did some load testing with an electronic load I built before and it appeared that the 2.1A is rated for the combined output from both USB ports. You can see my testing in the video linked towards the end of this post. This means that if you are charging two devices using this adapter, charging time will be lengthened as the 2.1A output current has to be shared between the two channels.
The internal build quality of this MVMT USB adapter is actually quite good. Two PCBs are used in this adapter. One is for surge protection and the other one is for the switching power supply that generates the 5V output rails.