My next project is a word clock inspired by drj113’s instructible on making a word clock.
My design differs from drj113’s original considerably
- Rearranged lettering on the front, giving am and pm yet maintaining a compact design
- Dimmable LED channels so that i can create smooth time transitions
- Light sensor so that brightness can be adjusted according to ambient light
- Superbright power LEDs on the back so that the clock can be used for dawn simulation.
I’ve also decided the frame of the clock will be aluminium, touching this aluminium should toggle the power LEDs on and off (with smooth transition).
Ok, so i designed my torch. This is fine but designs are no good unless you actually put them into practice. This is quite a quick build that goes together nice and quickly and has some nice satisfactory results:
I have this brinkmann 3xLED flashlight. I bought it in a walmart in the USA a few years ago for next to nothing. It isn’t very bright but the body is completely aluminium and the overall build quality is pretty good. I’ve been wanting to supercharge it for a while now so i bought some 3watt star LEDs from bestshop2008hk on ebay. My idea is to use one of these in the flashlight. I’ve put together a simple design to help accomplish this, including a way of heat sinking the LED to the torch case. Read more to see the design.
I’ve updated my bench power supply project description with a summary of the project (as follows):
This project started as me trying to fulfil a need for a reliable and convenient power supply and wanting to learn some lessons along the way. I designed the project in sketchup and then proceeded to go through various stages of construction. There were a few design changes along the way but nothing major. I decided to add an external voltage probe and a switch to allow voltage measurements either from the ammeter or ground.
- My Adjustable Voltage Circuit
- My Panel Meter Circuit
- My Aluminium Supply Case (Labelled)
- 2x DPDT switch
- Green Binding Post
- 4x Red Binding Post
- 4x Black Binding Post
- 3mm Red LED
- 6x 3mm Green LED
- 7x 3mm LED panel clips
- 4P2T rotary switch
- Amp Panel Meter
- Voltage Panel Meter
- Red Multimeter Lead
- 2x 6mm knobs
- ~20cm of 3mm 3:1 Heatshrink
- 2x TO-220 heasinks
- ~50 Crimp terminals
- Lead Free Solder
- 3x 47 KΩ resistors
- 3x 5.6 KΩ resistors
- 3.9 KΩ resistor
- 820 Ω resistor
- 12 KΩ resistor
- 1.8 KΩ resistor
- Soldering Iron
- Crimping tool
- Snipe nosed pliers
- Wire cutters
- Glue Gun
- Phillips screwdriver
- 2mm Allen key
For most of this it should be clear how it goes together. The circuit construction just followed my power supply schematic. If there is anything that needs explaining further then feel free to ask. Unfortunately i got a bit carried away at some parts and forgot to take photos, I’m still learning to take my time.
You may have noticed that my previous post shows strange labels for the rotary switch. This is because i’ve changed the function of the rotary switch.
The ammeter causes a small voltage drop and so when the ammeter is being used as ground, the effective supply voltage is different to when the actual ground is being used. As such i’ve made the switch have the following options for the voltage measurement:
- Variable voltage to Ground (VG)
- Variable voltage to Ammeter (VA)
- External probe to Ground (EG)
- External probe to Ammeter (EA)
As such the previous schematic for the power supply needs updating. Below is the updated schematic:
I think this is a slightly more useful design as it allows me to compensate for the voltage drop across the ammeter. The only function i lose is the ability to measure the fixed outputs. But considering the external probe should be able to do this, i don’t really mind.