Archive for the ‘Electronics’ Category.

A 400W (1kW Peak) 100A Electronic Load Using Linear MOSFETs

I bought a couple of IXYS linear MOSFETs (IXTK90N25L2) a while ago to test their capabilities when used as electronic load, and the result was quite impressive. So I decided to build another electronic load using both MOSFETs. As you can see in the video towards the end, this electronic load can sink more than 100 Amps of current while dissipating more than 400W continuously and can withstand more than 1kW of power dissipation in pulsed operation mode. Continue reading ‘A 400W (1kW Peak) 100A Electronic Load Using Linear MOSFETs’ »

Hacking Your Mouse for Rapid Firing

In this blog post, I will show you a simple hardware hack to make your mouse capable of rapid firing (or automatic continuous clicking). Of course you can always resort to software mods to achieve the same goal, but admittedly doing so in hardware is nevertheless more fun and as a bonus you also get an extra button. A video demonstrating this hack can be found towards the end. Continue reading ‘Hacking Your Mouse for Rapid Firing’ »

Teardown of a Vivitar Rapid Battery Charger

I just picked up a charger along with a couple of NP-FW50 spare batteries for my new Sony Alpha A6000 mirrorless digital camera. The Sony branded charger is ridiculously expensive, so I opted for an aftermarket Vivitar branded one (VIV-QCB-104), which retails for under $10. The charger is rated at 8.4V with maximum charging current of 600mA. Spec-wise, it looks fine for the NP-FW50 1Ah 7.4V battery pack. Continue reading ‘Teardown of a Vivitar Rapid Battery Charger’ »

Bertan/Spellman 225-20R HV Power Supply Teardown

I just picked up another high voltage power supply, this time it is a working Bertan/Spellman 225-20R 20kV one. Unlike the Bertan 205A-05R that I did a teardown with last time which was entirely analog, this one can be controlled digitally either via the front panel or via GPIB from the back. In this blog post, let me share some of the teardown pictures with you. If you are interesting in seeing some cool experiments with this high voltage power supply, you can scroll down and watch my video towards the end. Continue reading ‘Bertan/Spellman 225-20R HV Power Supply Teardown’ »

Bertan/Spellman 205A-05R High Voltage Power Supply Teardown

I got a non-working Bertan 205A-05R 5kV high voltage power supply and did an attempted repair video a while ago (see video towards the end). But I forgot to post my teardown pictures somehow. So here we go, better late than never. Continue reading ‘Bertan/Spellman 205A-05R High Voltage Power Supply Teardown’ »

How does Vacuum Cleaner Clean/Dirty Indicator Work?

I have always wondered how the clean/dirty indicator on my Hoover vacuum cleaner works. So when it was time to replace it with a new one, I opened up the old vacuum and took out the “dirt finder” circuit board. As you will see in the video below, it is actually quite clever! Continue reading ‘How does Vacuum Cleaner Clean/Dirty Indicator Work?’ »

Linear MOSFET and Its Use in Electronic Load – Update

In my previous post, I discussed why it is beneficial to use linear MOSFETs in electronic load and performed a couple of experiments using a single IXYS’ IXTK90N25L2 linear MOSFET. The electronic load was able to dissipate around 150W before the case temperature of the MOSFET reached 90°C. Continue reading ‘Linear MOSFET and Its Use in Electronic Load – Update’ »

Linear MOSFET and Its Use in Electronic Load

Power MOSFETs are widely used in switch mode applications such as pulse width modulated electrical motor controllers and switching mode power supplies. While they are also routinely used in linear mode applications such as power amplifiers and linear power supplies, standard MOSFETs are prone to secondary breakdowns due to hot-spotting or current focusing when operated in linear mode. Continue reading ‘Linear MOSFET and Its Use in Electronic Load’ »

A Dual Sensor Fan Controller Build

A while back, I added a fan controller to my Topward 6603A power supply. Later on, when I bought a used programmable power supply (PPS-2322) I had to do the same thing. Both of those builds were done on protoboards but I had a feeling that many of my other projects could use a similarly designed fan controller as well. So I thought why not just have the PCB professionally made? Continue reading ‘A Dual Sensor Fan Controller Build’ »

Teardown of a Static Fieldmeter

Static fieldmeters (or electrostatic fieldmeters) are typically used for non-contact measurements of the electrostatic field strength (usually in kV) of charged objects. These are highly specialized test instruments and most hobbyists probably seldomly have the opportunity of coming across one. So in this post and a companion video towards the end, we will take a look at how it works and what’s inside. Continue reading ‘Teardown of a Static Fieldmeter’ »

A Super Bright Light Source

I did a teardown of a SMART UF-55 DLP Projector a while ago, and later I showed how to hack the ballast board so that the discharge lamp could be powered without the rest of the projector circuitry. Continue reading ‘A Super Bright Light Source’ »

Adding Strain Relief to an Existing cable

Not all cables have proper strain relief built to the connector ends. This is particularity true for some of the iPhone 6 USB to Lightning™ cables. Take this Anker branded iPhone cable for example, after several months’ normal use the cable towards the USB end started to show signs of excessive strain (see image below). The internal wiring would soon be damaged if the strain on this area continues. Continue reading ‘Adding Strain Relief to an Existing cable’ »

Epson PowerLite 84 Multimedia Projector Teardown and Repair

I recently was given a broken Epson PowerLite 84 projector. The projector would not turn on when plugged in and there was no sign of life. So I decided to take a look at what was wrong with it. The potential reward is high since I do not have a projector yet and I could definitely use one for my home theater setup. A video of this teardown and repair is linked towards the end. Continue reading ‘Epson PowerLite 84 Multimedia Projector Teardown and Repair’ »

Wavetek 395 Arbitrary Waveform Generator Teardown

I picked up a Wavetek 395 arbitrary waveform generator on eBay a few weeks ago. Wavetek 395 is a single channel, 12-bit resolution DDS AWG with a maximum clock frequency of 100 MHz. While the operation manual is readily available, I could not find the service manual anywhere. So I was curious to see the construction inside. In this post, I will show you some of the teardown pictures. If you want to see a video of the teardown along with some analysis, you scroll towards the end of this post. Continue reading ‘Wavetek 395 Arbitrary Waveform Generator Teardown’ »

Hacking an OSRAM P-VIP Projector Lamp Driver Board

After taking the SMART UF-55 projector apart, I decided to take a look at the salvaged circuit boards to see whether I could re-use them to power the projector discharge lamp. Most of the modern projectors utilizes some kind of “smart” ballast circuits so that the main board could communicate with the ballast to determine the correct drive level given the required luminous level and monitor the operating temperature. Continue reading ‘Hacking an OSRAM P-VIP Projector Lamp Driver Board’ »