delabs-Portfolio

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In: Design, Handheld Portables

I once worked in Tek for a very short period. I got to experience the 2235 and 2465 analog scopes and their controls. The 2465 was a 400 MHz Digitally Controlled Analog Scope.

I also used the Plugin Scopes and Calibration systems that were Tek Culture and Tech contribution to the Instrumentation world, it probably evolved into VXI-PXI as uC systems took over.

delabs designs – The code has been moved from Google Code Hosting to github – delabs-dapj

delabs Web Widget and Application Interface Usability Experiments 2003-2008

I also had a chance to look at DSO/Logic Analyzers and the just developed TDS Series. The older tek analog scopes made me understand about usability and panel layouts. Many controls are inevitable in a Analog Scope with Electromechanical Interface.

In a Digital World that can be largely changed using the Monitor and Trackballs. The older BlackBerry phones are also good study for usability before Touch Screens came.

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In: Instrumentation, Power Electronics

This is a Regulated 0-30 V DC Power Supply manufactured by me in small numbers, 0-30V 5A and 5V -5A. It had a Switching Preregulator. This keeps the Vce across Transistor Bank at the Back of Instrument, at the lowest possible level, in order to keep them Cool. When Vce and Ic both are more in a Power transistor it will get heated more, then the efficiency of power supply is low.

Power Supplies Section – delabs

Variable Regulated Power Supply

The Output had both Constant Current Control and Constant Voltage Control. The CC control is also a Short circuit protection. The Output was protected from outside voltages damaging output circuits even when equipment is switched off. The back panel is a finned anodized black aluminum heat sink with many transistors.

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In: Process Control

Below is a Electrical Control Panel, It has a Strip Chart Recorder which is electro-mechanical, It has a PLC Inside. A handheld PLC Programming unit. The computer is showing the Ladder Logic Program. PLC is based on a embedded uC. The DIN Controllers are Analog + Digital circuits. So you see it is a Electrical Control Panel with Electronics and the PLC Ladder Logic means, Software too.

Process Control Application Notes

This is a PID Controller based Control Panel using a PLC from GE Fanuc Automation. The Computer is a 386 40MHz with 40MB HDD.

PID Controller PLC

Electrical Control Panel Wiring

Control panes have many DIN Instruments like Indicators, Controllers and Recorders. They also have in the back end contacters, drives and circuit breakers with orderly wiring and cable management.

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In: Basic Electronics

This is a demo of the popular 555 timer. you can try out the project on this page by a javascript simulation.Press the Red button below to turn on the circuit press it again to turn off. The 555 can source (LED2) or Sink (LED1) upto 200mA.

Screenshot of Astable 555 Timer Flasher

It can even drive a small motor or lamp with diodes added to protect from inductive kickback.Vary Ra, Rb and Ct with the controls given and see the change of frequency, period and duty cycle.

Screenshot

Astable Multivibrator with 555

Astable Multivibrator with 555

This is a tutorial with calculator to help learn the application of 555 which is a very rare chip innovation. It is simple, versatile, flexible and programmable (by tweaking of pots).