EMS Labs has many LEDs

Good spread of many types of LEDs for all the DIY or Prototype Projects. 10mm White Diffused LEDs for making lamps too. The 5 mm RGB LEDs with
Diffused-lens and four leads is the best one here.

in reference to: LED Headquarters (view on Google Sidewiki)

How to Learn Hobby Electronics

VE7BPO has a way of presenting easy steps towards your Hobby Lab. It is Ham or Amateur Radio DIY Community that caused the outbreak of Electronic Hobbyist Activity the world over, long ago.

Here the Two Transistor Astable Multivibrator for flashing LEDs, that got popular after low priced Plastic Silicon Transistors became available, Superseding Metal Germanium ones.

in reference to:

"VE7BPO"
- More LED Flashers (view on Google Sidewiki)

Dial based Analog Multimeter

In those days small firms used to make DPM's digital panel meters with 7107. In 1987 when i got a opportunity to design a DPM for a firm, I put the 555 clock in place CD4009 clock shown in intersil, to derive the -5. I created this design to study Eagle Editor. It is not tested by me, but all concepts/modules have been used by me in my designs earlier. It ought to work with some tweaks.

Analog Dial AVO Amps-Volts-Ohms meter

This was designed, keeping in mind, that sometimes we have few components available and we could be flat broke. Even that you could not carry your DMM somewhere, but you have to make some instrument for a quick need with what is available. If you are out of cash or feel like Robinson Crusoe, then this is a low cost measurement system.

How they used to measure with Precision before the advent of new technologies..... See the Instrument above. If you can afford it, buy it as a Lab God. Something you can worship before every new project. Its Presence itself will make you bow a few times before this "Stupendous Excellence". What Dignity and Bearing at this age, they don't make this kinda things no more.

ESI Electro Scientific Inc. 250 DA Impedance Bridge

LED Dimming Lamp

Build it or go for a kit, this is a nice design for a Table or Desktop lamp. You will need to fix in a Enclosure with a Diffused Plastic or Glass Filter Front.

in reference to: 18 LED dimmable LED lamp (view on Google Sidewiki)

Easy to Build Lux Meter - ELM

If you are building LED Lamps and Solar powered lighting, a LUX Meter and a Energy Meter is required to measure what has been achieved. One is the Efficiency of Power Conversion and Other is Illumination comparable to the lighting people are used to.

It would be better like a Mains Supply wiring, 230/110 all houses have a 24V DC Bus for LED and Solar and small appliances on power failure. There is no point stepping down and then stepping up the power. The combined efficiency may become like 60%.

ELM - Lux Meter

"The Lux Meter is usually used to measure illumination. The illumination is how level of luminous flux is falling on a surface area."

From - The Electronic Lives Manufacturing

LM3914 Dimming Flashlight

The LM3914 is used as the basis of a 10-step variable brightness current-regulated white LED torch!

A modification in this design may be to separate the LED Anodes from V+ pin 3. Give a Zener supply at 3. The LED anodes must be supplied a square wave from a LM555 pin 3 at around 200 Hz. This will reduce the dissipation as it is switching. LM555 can drive 500mA which is sufficient.

in reference to: Silicon Chip Online - Circuit Notebook (view on Google Sidewiki)