I have corrected, enhanced. moderated my design notes from my earlier Amps-n-Volts News Letter. This was sent thru Your Mailing List Provider for a few years. Even now some errors and misconceptions of mine, might still exist in these posts. Any feedback or correction is welcome.
Near 2001 i started sharing my learning and experience in Electronics Engineering on Blogs and Newsletters. One of the Successful eMag and electronic email magazine ran for five years. I lost interest later in the email mag, and this magazine just morphed into a dozen or more Tech Blogs that run today.
From the feedback i got, it has helped engineers and enthusiasts worldwide in Electronic Product Design.
My knowledge is limited to my experience, observation, perception, learning and beliefs, but i have to express my views freely. These posts are mirrored in design devices.
- Before you open a PC remove power, telephone modem and LAN cables else finger and screwdriver in wrong place can zap chips.
- The products that survive the infant mortality time of say first six months will last quite long.
- NTSC is like 320 x 240 pixels, which is TV, which is lower than your computer’s 800 x 600.
- When a microwave oven is turned on, a big spike is caused in the power line due to heavy inrush current on start up, Even pumps and motors cause such short time surges. This causes tripping of electrical protection circuits.
- When a tree branch falls on the high voltage overhead electrical lines, they spark violently and supply trips.
- Big or tall trucks go in small roads they may snap all low level cable or telephone wires on their way.
- Do you need to turn on many equipments-machines all at once? do it one after an other sequentially or use a timer for delays. This is because at peak power demand time, turning on all can cause your fuse to blow or worse.
- A battery that can be charged is best charged in CC constant current and CV constant voltage modes, that means both current and voltage have to be limited. When a battery is deep discharged many times it will age fast, and an empty battery will take huge currents so limit current. overcharging a battery will killit. After a voltage level is reached it should only trickle charge in mA and a battery has to be cut off on overload or before deep discharge
- The Lead acid battery breathes a lot, so keep them in a well ventilated open space but rain proof. Use sealed maintenance free battery when possible, these are safer.
- Teflon tape can be used to make leak proof pneumatic or hydraulic connections if junctions are leaking.
- The current thru a 3mm or 5mm LED (light emitting diode) should not exceed 20mA, 15mA is quite good.
- In a circuit swap all PNP and NPN , reverse all diodes and el-caps, reverse the supplies and input polarities, most of the circuit may still work like they did before.
- A sharp bend in a PCB track is a huge inductance (say 1nH ) when it comes to RF. it may radiate or reflect, it may even act like an antenna and pick up RF from the SMPS, Motor or Cellphones nearby.
- Persistence of vison around 16 frames a second (60mS) hence very fast events not seen .
Some of these points may be repeated and some not relevant in the present technical engineering scenario. As issues may have been set right, years back.
- Design Notes – Analog and Opamps – 01
- Design Notes – Power Electronics – 02
- Design Notes – Power Electronics – 03
- Design Notes – Schematic and PCB – 04
- Design Notes – Components Selection – 05
- Design Notes – Analog Basics – 06
- Design Notes – Product Development – 07