Category Archives: Projects

Postings of my projects.

PIC Programmer & Experiment Board

A few weeks ago I reignited my electronics hobby by purchasing a couple of “put it together kits” that were on clearance at RadioShack. The first kit I tackled was the Velleman K8048 PIC Programmer & Experiment Board.

Velleman K8048 PIC Programmer & Experiment

Velleman K8048 PIC Programmer & Experiment

I’ve played with microcontrollers/PICs in the past, specifically the Parallax BASIC Stamp 2.

Its an exxcellent kit for the novice at a reasonable price.

Parralex BASIC Stamp Activity Kit

Parrallex BASIC Stamp Activity Kit

Soldering the components on the Velleman K8048 board isn’t that difficult. If you don’t have experience soldering I highly recommend that you watch a few YouTube videos and practice with a few wires.

TIP: Solder likes to flow toward the hottest area.

After I had completed the kit I went to my drawer of power supplies to locate a 12v unregulated or 15v regulated DC output power supply. Out of the 20 or so power supplies none of them met the requirements. I figured I could either buy a new one or have some fun in building a variable output power supply.

My next posting will be part one of several covering my experiences with designing and building my power supply.




Digital Oscilloscope – QuantAsylum QA100

QuantAsylum QA 100 Digital Oscilloscope

QuantAsylum QA 100 Digital Oscilloscope

My personal electronics projects have progressed to the point where I need to use an oscilloscope to not only diagnose my circuits but also to further my education.

My research led me to a series of comments left on SparkFun. After looking at various other digital oscilloscopes I decided to give this one a try. This one appeared to be good enough to cover majority of my near future projects at a reasonable cost.

NOTE: This oscilloscope is also my first personal scope and using a digital one. I had used various analog ones in high school and college.

I’ll be posting more about the scope as I use it with my projects. I’ll start with some very basic uses during my power supply project.


Additional information on the QuantAsylum QA 100 Digital Oscilloscope can be found here.

Build Your Own Moisture Sensors Using Nails

I’m constantly scouring other peoples projects looking for ideas. Devon’s  PiPlanter – A Plant Growth Automator project cleverly uses nails and the conductivity of water within the soil to measure soil moisture.

The result of planting wild flower seeds this spring in a 16" terracotta pot.

I’ll have to give this a try with the soil in our terracotta pot. We’re finding that the wild flowers we planted are very sensitive to low moisture. For example, we’ve had rain nearly a week straight until 2 days ago. Last night we noticed that the flowers were drooping already! A few pints of water and an hour later they were back to full strength.


Shelf Over Washer and Dryer

This isn’t a major project but very useful. The shelf is a 1×10. I used my sawhorses and Porter Cable 7-1/4″ circular saw to cut it to length. I offered to stain it but my wife liked the natural color.  I didn’t want the shelf to be permanent nor do excessive damage to the drywall so I used #12 2-1/2″ finishing nails around the perimeter for the board to sit on.

Simple 1x10 shelf

Simple 1×10 shelf

Raised Flower Bed

When we moved into our house the fenced-in backyard was in rough shape. There were two large bare areas each about the size of a 4×8 sheet of plywood. I spent one afternoon working garden soil into the areas and reseeded the yard. I watered the yard each day for the next 3 weeks and nothing was growing in these bare areas; not even weeds. My wife and I brainstormed our options. We both hypothesized that the area must have been contaminated by construction materials so whatever we did it we would want a little separation.  Therefore we came up with the idea of creating a 5×9 raised flower bed.

5x9 raised flower bed w/o flowers

5×9 raised flower bed w/o flowers

Building the flower bed wasn’t hard with the help of my wife to hold the frame up while I attached the boards together. I bought 3 – 2x10x10 pressure treated boards. I cut 1 board in half and cut off 12″ from the other two. Used 3-1/2″ exterior wood screws to secure the corners of the boards. Once all four corners were secure I used scraps of 2x4s approx 16″ long to brace the corners and keep everything square. Additionally the braces double to up to accommodate for the uneven ground thus keeping the top of the boards level.

Finished Product

Raised Flower Bed with Flowers

Raised Flower Bed with Flowers

Recent Picture (08 July 2013)

Picture taken 08 July 2013

Picture taken 08 July 2013 – We have squirrels and chipmunks/ground squirrels so I added the corn platform.



Working in the Rain

Our spring weather has made certain projects challenging.



Growing up in Iowa I took part in many useful actives such as gardening, farming, metal working, fixing mechanical items, etc. However, woodworking/carpentry was one area that I didn’t explore. I don’t know why. I had the opportunities to learn from the best. My uncle, Randy, is an incredible and respected craftsman who has been in the carpentry business over 35 years. He’s done it all. Anyways, I figured now would be a good time as any to start this journey and why not start with something simple, useful, and fundamental – sawhorses.

Helpful Tools

  • Sawhorse plans – A Google search will turn up several hundred results. I chose the I-beam simply because I liked its looks.
  • Saw – I chose to purchase the simple and versatile 7-1/4″ circular saw (Porter Cable)
  • 15 amp extension cord
  • 3″ wood screws
  • Square
  • Pencil
  • Tape measure
  • Phillips screw driver – I chose to purchase a cordless drill (Porter Cable 20v)
  • Eye and ear protection

The amount of wood is dependent on the plans. The trick is to plan your cuts ahead of time so you can minimize the waste and costs.

Tools and Materials Used

untreated 2x4s, cordless drill, ear and eye protection, plans, pencil, 3″ wood screws, 7-1/4″ circular saw, 15 amp extension cord, square

Finished Product

Finished Sawhorses

Set of sawhorses using untreated 2x4s


If anyone is looking to jump into woodworking I highly suggest starting with sawhorses. It’s a small project that can be finished within 90 minutes. Additionally, it’s one of those projects that if you make a mistake it’s not a costly one. A 2x4x10 even pressure treated is less than $5.

There are two small items that I will change the next time I build a set. The first one is to make sure the plans are for stackable sawhorses. The other item is to adjust the height of the sawhorses to match my height vs the average height.

Lastly, once you have the sawhorses built you can graduate to larger projects, such as a flower box, that will put your sawhorses to good use.



Building a Power Supply – Sorting Out Voltage Readings

<post photo of setup>

My previous posting/project, PIC Programmer & Experiment Board, created the opportunity to build my own power supply. A Google search will turn up many design variations, but the most popular is to use an AC transformer, 4 diodes or a full rectifier, capacitors, resister, fuse, and a switch.

As I was testing the transformer and full wave rectifier I noticed a significant difference between the AC voltage output from the transformer and the DC voltage output from the rectifier. It was large enough that it made me want to investigate.



Radio Shack – 25.2V Center Tap 2.0A Heavy-Duty Chassis-Mount Transformer with Lead
Model: 273-1512| Catalog #: 273-1512

You will often see transformers with 2 input lines and 3 output lines like this one. The voltage between both yellow lines for this model will peak at approx. 25.2V up to a certain amperage. The voltage between the center tap (CT), which is the black line, and one of the yellow lines will be at approx half (12.6V) of the full capacity (25.2V). This is because the CT is a line from the middle windings of the transformer.

Transformer Voltage Readings – From Center Tap

<picture of voltage>

Notice the multimeter voltage reading of 13.87 AC and the oscilloscope’s peak voltage reading of 18.7 AC (peak to peak = 37.4). How can this be?

Turns out most multimeters report the root mean square (RMS) of AC voltage. The accuracy of the reading is highly dependent on the circuitry of the multimeter and the wave being measured. The higher-end models will have the ability to sample more frequently thus provide more data to calculate RMS.   RMS also represents the DC voltage equivalent of the AC voltage that delivers the same energy.










Fogger Fun

This year for our Halloween display I purchased a fogger at my local Lowe’s store. It worked exceptionally well. My only complaint was it didn’t automatically produce fog. It required someone to manually operate a rocker switch.

Fogger and Control

The existing hand control is 115v AC based. The green light indicates the fogger is ready and the red rocker switch sends power to the fogger’s pump and produces fog.

The main concern is to isolate the 115v AC from the lower voltage circuitry both for the indicator and to drive the fogger.


I chose to use the H11AA1 Optocoupler to handle the indication that the fogger is ready (Green Light). The H11AA1 is designed to accept AC on one side (pin 1 and 2) and DC on the other (B,C,E). When the AC side is hot two tiny LEDs inside the chip will turn on. The DC side has a photodiode that will detect the light and allow DC current and voltage to flow via pins B, C, and E.

Screen Shot 2013-11-23 at 8.49.48 PM

I chose to use a mechanical relay to handle driving the fogger to produce fog.

Playing with Electronics – The Beginning

Around 1985 or 86 I got one of these for Christmas.

Around 1987, give or take a year, I got a similar one for Christmas. I’m not sure if I had a Gakken, Skilcraft or a Tron Link. I also don’t recall the version. I’m pretty sure it had to be either the EX-100 or below. (image found here)

What I can I say, being around the Apple ][ plus and wondering what those circuit boards captured my interest. It also helped that during this time I was watching shows that incorporated modern to futuristic technology: Superman III, The Wiz Kids and my all time favorite, WarGames, used computers, Small Wonder used an android, Knight Rider had KITT. I can’t forget Star Wars and its robots. All of these and more influenced me.

I have no idea how I articulated this want on my Christmas list that year. I’m pretty sure it was 1987 because that Christmas my sister got an interactive talking Juile doll (to this day that doll is creepy cool). I do remember opening up the present and immediately wanting to play with it. I remember my Aunt Sandy and Uncle Ed helping me with it; none of us really understood what we were doing. I remember trying out the lie detector tester and it being such a disappointment. We could tell it truths all day long and it’d flag it as a potential lie.

Overall, it was a neat kit. I was definitely interested and wanted to learn but I think my interests fell into the crack. I wasn’t old enough to demand my parent to help me find someone that could help explain the experiments nor was I old enough to be able to figure it out on my own. Today when I read about Steve Wozniak and other early Silicon Valley kids I read in envy. Why? Because they access to people all over their neighborhoods who knew a thing or two about electronics. I hit my maximum level of frustration with electronics with this kit and moved on. I am thankful that my parents did what they could and at least gave me a shot at learning electronics with this kit.

Interests Rekindled

Training kit with a fully working Allen Bradley Micrologix 1100 PLC

Training kit with a fully working Allen Bradley Micrologix 1100 PLC

My interests in electronics was rekindled in 2010 while I was working on a software project for a waste water company out of Charleston, South Carolina. That project required me to quickly learn about Programmable Logic Controllers (PLCs). In fact I purchased an excellent complete Allen Bradley MicroLogix training kit off of ebay from plc_trainer aka Ind-Concepts. Additionally I purchased a used Allen Bradley analog module off of ebay for the PLC.


While I was working on the waste water project I also purchased a Parallax BASIC Stamp Kit. More recently I’ve purchased a RaspberryPi Model B and an Arduino Uno.