Here is a collection of interesting videos on microphones and microphone technologies: Audio 101: Microphones Dynamic vs Condenser Microphones, What’s the Difference? Audio recording tutorial: The different microphone types | lynda.com XLR vs USB Microphones, Which Should You Buy? $22 MICROPHONE VS $3600 MICROPHONE | Andrew Huang Voice-over Microphone || DIY or Buy How a →
Android smartphones and PC use TRRS headset connectors. You can find details on that interface on my Telephone handset to smart phone and laptop posting. Ealier PCs used two TRS plugs (mic and headphones) for headsets. Because both connection types are still in use, sometimes adapters are needed. Here are some details of those adapters. →
I did earlier a teardown of broken Behringer B208D active PA speaker. Now it was time to get ot fixed. The problem was that sound level before distortion was very low and bass was missing. It seems that low frequency driver could output only 1-2V signal to speaker before distortion, and to get that the →
I wrote around two years ago a blog posting on RJ-45 Ethernet surge protection. Now it is time to check out what is inside one cheap Ethernet surge protector. The product here is very cheap (around $2) CY UT-013 Lightning Protection RJ45 UTP STP CAT6 CAT5e Female to Female Network Lan Adapter Extender. The specifications →
Here is tear-down of cheap USB 2.0 to CAT5E CAT6E RJ45 LAN Modem Extension Extender Adaptor for Webcam XBOX adapter. This adaptor is designed to allow your USB cameras, printers, webcams, keyboard, or any other USB device to be situated some longer than normal USB cable (few meters) distance away from PC. This converts USB →
I ordered this cheap (around $10-15) 5.1 channel USB sound card from China few years ago. The device does not have markings on the box so hard to day which exact model it it was. It seems that there are several similar looking cards available at dx.com and banggood.com even today. CM6206-LX based USB Sound →
Here is teardown of a broken Samsung J5 smart phone (SM-J510FN from 2016). Let’s open it: A Closeups of circuit board Not too much to see. Many parts were covered with metal cases soldered to circuit board. I did not see here any easy to fix problems (like loose connector) that would have allowed to →
This is a teardown of one broken Ethernet to 3G cellular network industrial gateway. There is a miniPCI slots for communications module. It is a commonly used for cellular cards. MiniPCI slot provides both PCI and USB signals. This Option GTM382 cellular module has USB 2.0 host interface (uses AT commands). There there seems to →
This is a teardown of Behringer B208D active PA speaker. Inside Here is input pre-amplifier Look inside power electronics metal box Inside here is swich mode power supply (mains to around +-27V) and amplifier board. Amplifier board has 160W class D amplifier chip (below board and possibly broken) for driving low frequency speaker element, 40W →
For controlling stepper motors you need a suitable controller. It is possible to build controller using discrete components, controller ICs and using micro-controller. It can be fun to build our own stepper controller, but when you have done that few times, you might want to start looking or reasonably priced ready made easy to use →