San

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A Low cost A/D with a Potential of 5KV Isolation from Computing elements by use of Normal/Special Opto-Couplers. This can give better resolution and accuracy than a 8 bit A/D. may be close to 10 bit A/D. Added advantage is that you can optically isolate the inputs.

Convert Analog to Digital with a V-F

Suppose your temperature sensor touches a heating element OR your speed sensor is subjected to a shock from a defective motor with earth line broken. Such situations happen in the field, even at home or lab. Sometimes it is carelessness, other times it is wear-tear. Many times it is breakdowns, accidents etc. So do not let the High voltage to get at your Microcontroller Board.

More about Embedded Micro here – Hyper Embedded

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Radio-Electronics was an American electronics magazine that was published under various titles from 1929 to 2003.You can Read them all here .

Radio Electronics Magazine at The Internet Archive

Recently i found a collection of those mags at Archive.org …..

Radio Electronics Magazine at Archive.org

Hugo Gernsback, sometimes called The Father of Science Fiction, started it as Radio-Craft in July 1929. The title was changed to Radio-Electronics in October 1948 and again to Electronics Now in July 1992. In January 2000 it was merged with Gernsback’s Popular Electronics to become Poptronics.

Gernsback Publications ceased operations in December 2002 and the January 2003 issue was the last.

Over the years, Radio-Electronics featured audio, radio, television and computer technology. The most notable articles were the TV Typewriter (September 1973)[1] and the Mark-8 computer (July 1974). These two issues are considered milestones in the home computer revolution.

Radio Electronics Magazine at SWTPC

Radio-Electronics was aimed at electronics’ professionals such as radio and TV repairmen. And they were men, the tag line on the cover was “For Men with Ideas in Electronics”.

Radio-Electronics & Electronics Now

Radio Electronics was the “new” name for Radio Craft magazine.. Hugo Gernsback, sometimes called The Father of Science Fiction, started it as Radio-Craft in July 1929. The title was changed to Radio-Electronics in October 1948. In July of 1992 transitioned to “Electronics Now

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40 Watts Hi-Fi Music System

Stereo Music player with Tuner, 1986, LED VU meter and Analog VU meter.

SAN 20

This was done as repairing home electronics was my hobby in school days, I learnt by building Amplifiers based only on transistors from the Old Philips Circuits and Books.

Home Made Circuits

The above one is TDA2020 20 Watts Per Channel, with LED input level meter and moving-coil output meters. It would have a 5 pin din input and RCA speaker output, input for phono, tape, etc. The Speakers had a woofer, tweeter and midrange with passive crossover network.

SAN 20 Speakers

Stereo Adapter for Portable Music Player

Low Cost Stereo Adapter 20 Watts for Portable Music Player 1984, Bass Treble and Presence.

Portable Music Player

This was a TB810 based 10+10 Watts Stereo Amplifier with LM381 or 2 Preamplifier, The portable player docks in a wooden cabinet. There was no IR, Wi-Fi or Bluetooth in those days, so the device would interface with amp thru a stereo ear-phone socket-jack system with a shielded cable. Bass, treble and Presence as per an old phillps audio amp book.

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Systematic and Meticulous work has its own Rewards. An Engineers Notebook or a Hobby Experiments Log Book can go a long way in making a Cauliflower out of every Cabbage. (The credits of the Vegetable Analogy goes to Mark Twain)

1. Keep Work Place Clean.

Clean Tables and shelves every day before closing office, Put Cut leads and Solder shots in a separate cup to be accumulated and disposed later as these are toxic. In this cup other irritants like staple pins can be added and these can be clubbed in a month and disposed off as one metallic bulk for recycling. Never bring coffee or food to work area, Keep a waste paper basket on your side.

2. Work carefully to avoid injury

When cutting leads hold the lead in the hand and cut or it will fly all over the place. A piece like that may land on another equipment and cause shorts or it may go right into your eyes and cause blindness. Lead and Iso propyl alcohol and other Chemicals may be dangerous for health if handled carelessly. Do not use fingers, and teeth as tools it is bound to cause a injury to repent a lifetime. Be extra careful with 230V AC and more so with 440V 1 tr 2mA thru your heart and a weak streak of luck may be the last experience you ever had. Do not press your Luck too hard.

Electronics Work Culture and Discipline

3. Protect Desk or table surface.

If you are cutting something let it not leave marks on table, even adhesive stains should not deface table, use a asbestos, Bakelite, fiberglass, hardboard surface which can be disposed once in a way. Before working put two layers of news paper on the table this prevents table from getting spoilt while soldering and newspapers being hygroscopic (water absorbent) they provide a natural antistatic surface to protect CMOS Ics and are nonconductors for any Live PCB kept on the paper.

4. Use tools and equipment’s in a gentle manner.

When you use weller Iron use it as a heat transfer tool never use it for prying or crimping leads or just pressing use pliers or other tools for that.

5. Document what you do and vice versa.

Have a register in which you can make records of what you did to solve a problem or what you learnt while making an equipment this information is valuable for the company to develop production methods and also useful to your team to solve a similar problem. Share abilities and skills with fellow employees but don’t share your company’s technology and database with any other company. When you leave a company use only the abilities and skills in that broad area to evolve as a professional.

delabs notes – 80s and 90s