Electronics Design

Transformerless LED supply idea

I saw the following circuit design posted to Facebook. Source: https://www.facebook.com/share/p/1HuYVvXHcf/ What is wrong with this design: No isolation from mains, potentially electrocutes if you touch any part of exposed LED strip. The circuit will only give around 220V/30000ohms=0.00766.. mA current that can light one normal LED but not any long LED strip like shown

Bad amplifier design

I saw this at Facebook at https://www.facebook.com/share/p/1YitRKKmxy/ Can burn loudspeaker and transformer due DC flowing Dc quite probably saturates transformer core-> lots of distortion and very little sound Even if works the transformer is expensive and limits sound quality Very low impedance sound input is less than 30 ohms – which means this circuit does

Touch switch

I saw this circuit at https://www.facebook.com/share/p/16HFEwzkcQ/ The diodes try to charge and discharge the mosfet gate based on static electricity of user touching. Depending on the amount of charge you happen have it might not work at all, might work or could fry the mosfet (they are static sensitive components). FETs are extremely vulnerable to

Phone line over voltage protection

This is a telephone line over voltage protector. This is basen on a design I did originally around 1995. Has been available for almost 30 years. That white thing is a deal gas discharge tube over-voltage protector that dissipates most of the over-voltage surge. It is followed with two other layers of protection (VDR and

NPN and PNP transistors

There are two main types of transistor: bipolar junction transistors (BJTs) and field effect transistors (FETs). The invention of the transistor in the 1940s was a major turning point in the history of electronics. The bipolar transistor was the first transistor to be invented, when one simply says “transistors,” it sometimes means bipolar transistors. BJTs

VituixCAD

VituixCAD is loudspeaker simulation software. Design philosophy is to simulate loudspeaker behavior in full space or half space. Even though emphasis is on power response, polar responses and directivity index, it is possible to design a loudspeaker without comprehensive angled measurements. This is not encouraged though. Software package includes everything one needs for simulating and

Low resistance measurement

There are applications where measurement of low resistances are needed. Measuring low resistance helps identify resistance elements that have increased above acceptable values. How you measure low resistances below one ohms? Most multimeters aren’t accurate below 1 ohm. Occasionally, you’ll need to measure electronic parts with very low resistances, such as wires, switches, current-sense resistors,