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.
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
- 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 or 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