Introduction

In the video below I cover adding a larger battery to an APC Back-ups 350 or 450.

Items You’ll Need

A 12V 9Ah lead acid battery
A Dremel tool with cut off wheel.

The Hack

The hack takes advantage of the fact that the 350, 450 and 550 APC UPSes use the same enclosure.  The 350 and 450 have extra supports molded in to support a smaller battery.  We need to remove these supports so the larger battery fits in the compartment.

Conclusion

This is a nice upgrade for those times when you need a little extra run time.

Introduction

I’ve been working on a project that required 3 stepper motors. Well Ebay is the best place to get them cheap. Not many of them are 8 wire these days.

Superior Electric M061-FD-6102 Specifications

Leads: 8
Voltage: 11.2V
Current: 0.44A
Step: 200/rotation

Wiring diagam

 

drive 1 ---------[red]-----)   (-----[green]------------ drive 4
                           )   (
                           )   (
          |----[black]-----)   (-----[orange]--------|
     +V --*                  0                       *-- +V
          |----[white]-----)   (-----[white/black]---|
                           )   (
                           )   (
drive 2 ---[white/red]-----)   (-----[white/green]------ drive 3

Introduction

We like to garden inside as well as outside. And wouldn’t you know it, we don’t get much sun in the house. I built this grow light to use on a 4 plant hydroponic garden I built. My test subject for this light will be herbs.

Overview

The colors we are interested in for our light are red and blue. Different LED lights you can buy have differnet ratios of these two colors. There are excellent articles on the internet describing how plants use these two colors. Now if you want to view your plant’s natural beauty then this is not the light for you. For this light I used red and blue LEDs. I used 3 red LEDs for every Blue LED. Hopefully this provides some good results. If you want to view your plants then you’ll have to build a light using white LEDs.

Specifications

I built the light on perf board. See the pictures for the layout. The light draws 10.7 watts of power and runs on 12V. 1.5W is dissipated in the resisters. I used 136 LEDs and 34 100 ohm resisters.

Construction

Please use the pictures as a guide for construction. Each row contains a 100 ohm resister and four LEDs in series.

Greatly dimmed so you can see the LED colors.

Top view of Light.

Bottom view of light.

How Much Light Do You Need?

This is prob the biggest question. Depending on what you are growing you’ll need from 10W to 40W per square foot. Lettus and herbs will need 10W to 25W per square foot. And vegetables will need 25W to 40W per square foot. What you are aiming for is 50% to 70% of the watts per square foot used by an HPS light. For example if you use a 250W HID light you would need at least a 100W LED light.

What Can I Grow?

The ratio of red to blue is important to plant growth. This light has a high percentage of blue light. This makes it well suited for non flowing plants such as herbs.

Conclusion

This is an extremely bright light. It should provide enough light for a small garden. By small I mean less than 1 ft by 1 ft.

Introduction

I needed a bench top power supply for prototyping PIC microcontrollers. I also had my PIC programmer looking for a home. Well combining the two together created a nice piece of equipment.
The PIC programmer is an old parallel version.  It can still be useful for many people.  I have upgraded to a USB version these days.

Overview

This is nothing more than a PIC programmer kit mounted on top of a power supply. You can buy/build the PIC programmer of your choice. The programmer gets its power from the power supply.
The power supply provices 5 volts at 1 amp and 12 volts at 1 amp. When plugged in the power supply powers up the programmer. The front switch controlls a relay which supplies power to the front terminals.

Schematic

The schematic lists the part values. This is a standard power supply design based on the LM7805 and LM7812 voltage regulators.

Right click on the image to view/save a full size version

Pictures

Here’s some pictures of the inside of the power supply.

Conclusion

There’s nothing better than a PIC programmer built on top of a bench top power supply. Just add a prototyping board and a computer and you’re good to go.

Introduction

For under $10 you can buy christmas light sets that flash the lights in different patterns. These sets have a small controller that animates the lights. The light set I chose cost $7.99 and were purchased from Big Lots. The lights can be removed from the controller and plugs installed.

Disclaimer

This project works with items that run off of AC mains. Only qualified persons should consider attempting this project. This project is meant as a guide. Your controller may be different from mine.

The Parts List

• 1 x set of chasing Christmas lights
• 3 x green multi outlet extension cord
• 6 x crimp butt connectors

Tools

• Wire cutters
• Wire strippers
• Crimp tool

Prepping The Controller

1. Remove the lights from the packaging.
2. Identify the main power leads going into the controller. It should be two wires connected to the AC plug. You may want to place some tape on these wires to identify them. We will not be altering these connections.
3. Next we need to identify the wires connected to the lights. Follow each wire to the first light it is connected to. We are going to leave one light connected to each wire. This will let us identify each channel. Cut the wire that is connected between light 1 and light 2. The controller I had gave me three channels. So I had three lights.
4. The last wire to cut is the return wire for all the lights. About 12 inches from the controller cut the wire. Strip this wire back 1/4 inch.

Prepping The Extension Cords

1. Cut the AC plugs off the extension cords. You should be left with the AC receptacles at the other end.
2. Separate the cord back 2 to 3 inches.
3. Strip each wire back about a 1/4 inch.

Putting It Together

I bet you’re wondering why we left one light connected to each channel. Its an easy way to identify the wires.
1. Twist together the wire without a light connected and one wire from each extension cord. Using a crimp connector secure the connection. This forms our common wire.
2. For each of the wires with a light connected do the following. Cut the light off the wire and strip the wire back 1/4 inch. Twist this wire with the un-crimped wire from one of the extension cords. Using a crimp terminal secure the connection.

Notes About LED Lights

Some sets of LED Christmas lights will work with the controllers. The LED rope lights sold by Costco work fine. LED light sets with 35 lights work fine. Home Depot is also selling LED lights that work as well.
The controller rectifies the AC into pulsating DC. Many LED light sets have half the LEDs wired to handle one half of the AC cycle. And the other half of LEDs are wired to handle the other half of the AC cycle.

How Many Lights Can Be Connected

Many controllers were design to run 150 to 200 lights. My controller ran 150 lights and drew 0.6A of current. My controller has 3 channels. That works out to 0.2A per string of lights.
Using standard Christmas light limits what you can do. At 0.2A per channel the max number of bulbs would be 50. That’s only one string of lights per channel.
Using LED Christmas lights gives you a great show. A string of 50 LED lights I have use 0.05A of current. That means that we can use 4 strings of lights per channel. That’s 200 LED lights per channel or 600 LED lights per controller.

Conclusion

This project was a great way to animate my holiday lights. Don’t forget to check those after Christmas sales for the best deals.

DISCLAIMER