Simple Electronic Devices and Hacks for Every Day Preparations, by Pat in Oregon

Sunday, Oct 16, 2011

Technology is a significant force multiplier in emergency situations.  There are several options I’ve found in my preparations to incorporate electronics into our everyday use and emergency preparations.  Hopefully these ideas will be of use and get others thinking about possibilities.  My goal in utilizing these ‘gadgets’ is to increase availability of resource while decreasing maintenance and effort – all at low cost if possible.  I’d like to share a few of the low-cost options that are simplest to try that we’ve adopted in our preps.

I’m an engineer and realize most of the tools I use won’t be appreciated by everyone, but I do recommend that everyone invest in a simple Digital Multi-meter.  They are quite inexpensive (as little as $15) and useful for troubleshooting automotive and equipment electrical problems.  They are easy to use and with all the information and tutorials on the internet anyone can begin taking advantage of their use.  Besides this tool, the rest of my recommendations are targeted to anyone of any background.  There are several helpful electrical gadgets we’ve found and use that have many broader options.  The best part is that these ideas will hopefully start generating interest or ideas of your own.  Realistically most adults won’t start collecting schematics or advanced electrical tools, but they can start learning new things, or may have friends or better yet, children, who are interested in pursuing these areas more.

Some simple things, first.  In a big family we have need for a lot of flashlights.  The kids use them often and so we often find batteries are dead when we need the light most.  On eBay we have found many Chinese suppliers of low cost, solar powered LED lights that have dramatically decreased our monthly expenditures for batteries.  Sure, these lights are cheaply made (you get what you pay for) but work great for everyday use.  Do a search for “Solar LED keychain” on eBay and you can easily find them for less than $1 each ($0.73 on average).  Over the course of a month we accumulated 10-15 of these lights and they all work great.  They are cheaply made and break easily, so think of them as disposable and to keep the kids from wearing out your more dependable gear.

Another good source of solar LED lighting is the inexpensive outdoor lamps available at all hardware stores.  Wal-Mart sells them for ~$2.  We keep these lights all around our chicken coop, outdoor buildings, and garden to help keep deer and predators away.  They also contribute to security and our own convenience when out-n-about at night doing chores.  They are inexpensive enough to proliferate anywhere needed and require no maintenance.  Another option is to use electrical tape to blacken the side of the light facing our home to improve visibility, or to help minimize visibility of our place from roadways.  Keeping these lights about the chicken coop also has improved egg production and extended the laying season longer into the dark days of winter.

EBay is also a great source for inexpensive wireless door chimes and passive infrared (IR) motion detectors.  For $3 each we picked up a number of different devices to test out as deer and predator alarms.  Some devices work great, others are less effective.  All are effective at detecting our dog at 6 feet, and many will see the dog as far away as 30 feet. For less than $10 we have a wireless perimeter around the chickens that detects any small animal movement and provides loud alarm to deter intrusion and warn us of detection.  Another $20 watches over our half-acre garden from deer or elk intrusions.   The alarms seem to deter the deer better than when we left a radio on out in the dark, and do well to give us and the dog a heads-up that marauders are probing the defenses.  The dog is learning well to respond to the cheerful doorbell chimes when they go off.

We purchased a more expensive IR detector that turns on a sprinkler when deer approach the garden and it has worked well, however it requires us to leave the hose on all night, and is too expensive to deploy in adequate numbers to cover all the fruit, garden, and other vulnerable locations on our place.  These low cost wireless chimes have worked very well for us to provide numbers and coverage.

All of these devices use the smaller, “pen-light” batteries and require replacement every few weeks.  Being an engineer, I’m always looking to ‘improve’ original designs or modify them to my unique needs (or wants).  I hate stocking and replacing batteries, so the logical next step was to combine the solar panel from the LED lights to power these wireless motion detectors.  Simply disassembling the LED lights and wiring the power (red) and ground(black) wires into the motion detectors has eliminated the battery need.  Some motion detectors require more power than others, but all the ones we’ve tested are adequately powered by the solar cells.  If more power is needed, simply use two or more solar cells daisy-chained together to boost the voltage to the detector.  Dropping a clean plastic container over the top is adequate weatherproofing that will not hamper the detector too badly, though I recommend spending time to make a more robust enclosure for your device to ensure longer life and use.

Another option to consider with these low-cost LED devices is to make an emergency charging circuit for your cell phone or handheld gadget.  The landscaping lights are recommended for this option.  Again, simply connecting multiple lights in a daisy chain and wiring a surplus USB cable to the mix works well for charging a FRS radio.  If you disassemble the light, you will discover one or more rechargeable battery inside – usually an “AA” size.  This can be removed and used as needed, and then replaced to recharge in the sun.  Some lights we’ve looked at have the battery soldered or “fixed” in the light, and others use a non-standard size battery, so do some snooping before purchasing in quantity.  Many of these solar devices have a single 3.6V battery.  The cheap keychain lights, for example, are sufficient to power a small “spy” camera that is the size of a car’s FOB, and can power the small camera to record video for up to 3 hours, continuously.

I wanted a more ‘discreet’ warning system around the chicken coop than the loud siren of the motion detectors provided, and found that by simply cutting the wires to the small piezo speaker inside the detector and connecting a separate LED to those wires, the detector gave a visual instead of a verbal warning to me.  Individual LEDs in various colors are available from Radio Shack or online for pennies.  The longer wire on the LED connects to power, the shorter one to ground, though on the speaker’s wires it doesn’t matter which wires the LED connects to.   I inserted the LED into a small tube cut from a pen, and now the LED indicator became very discreet and directional – only seen in the direction the LED was pointed.

There is another alarm available for very low cost to detect movement.  Small magnetic alarms that commonly are attached to a door or window are available at our local “Dollar” stores, and have a piercing alarm when the smaller bar is taken away from the main unit.  Besides their obvious use for detecting unwanted entry into your home or shop, these alarms work great to ensure the kids don’t forget to cover up the chicken feed bin, or leave the coop door open, or any other ‘reminder’ you want to keep a door closed.  I like to turn one on and throw it into the boy’s bedrooms on those mornings they haven’t gotten out of bed by the 3rd call!

As a science project with the kids, we created a GPS-based device that we wanted to launch with weather balloons of helium to track wind patterns, and to set adrift in the ocean to watch water currents.  First, we designed a custom circuit and software to record the GPS track, but in the end we found a much better, low cost solution that has many other applications worth considering.  Instead of a custom circuit, we found that on eBay we could purchase an older cell phone (I recommend a Motorola i415) with GPS capabilities for less than $10.  For another $6 we got a pre-paid phone SIM for the phone.  Using an on-line service for real-time cell phone tracking, we could watch the cell phone travel in real-time, and get our GPS data even if we never got the cell phone back from the ocean.  These phones make great, low-cost equipment tracking similar to Lo-Jack for much less cost.  A possible option for farm equipment, shipping container, or other large item you want to keep tabs on.  Gluing a strong magnet to the phone and modifying the charging cable would allow you to place the phone under the hood, wired to the vehicle’s battery for constant power. 

Rather than running 120AC power out to some of our remote locations, we’ve chosen to use car batteries for lighting and power needs instead.  It is great having a spare battery or two on hand, and with inexpensive solar arrays it is easy to keep them charged and available.  I’ve wired our garden house to use low-cost LED lighting strips, which run off the battery.  The solar panel easily keeps the battery topped off and ready for the infrequent use and the 12V is a standard supply for most battery powered devices and gadgets to run off, too.

With 12V readily available, there are a couple other electrical devices worth mentioning.  Various Internet sellers and eBay have remote controlled relay devices for under $15 (search for “12V remote relay”) that are great for remote control of any motor, light, or device.  They are simple to wire up and use, with little electrical experience needed.  It is nice when the lights are left on out in the garden house to have a remote control by the window in our house to simply click, and turn them off.  This gives all kinds of options to our OPSEC considerations.

For locking or mechanical actuation, I love using inexpensive, 12V automotive door lock solenoids.  Again, for less than $5 these can be had and applied to any number of uses.  We lock our chicken coop door at night with a door lock solenoid (remotely controlled, of course).  These solenoids are very strong (more than 7 lbs of pull in some cases) and work well to flip a wall switch, too. 
Two options we are using for power generation include solar panels and hydro power.  Neither option is able to generate more than 150W of power, but that is adequate to charge a single or bank of 12V car batteries.  Car batteries are the power supply of our choice because they are readily available, stable, and carry significant electrical power.  They are robust for charging and 12V is a common input power for many handheld devices.

I do not believe 120V AC is a viable option for TEOTWAWKI.  It requires extensive resources to generate and is neither safe nor versatile.  We do have several generators for running our freezers and power tools, but in a dramatic or long-term scenario, our plan is to rely on gas-based power tools (i.e. chainsaws, generators, rototillers, etc), propane powered stoves and refrigeration, and DC power based communications equipment.

Solar panels are readily available and easy to use.  We have several that are 40 to 50W, and with an inline diode to protect from back current, they work well to maintain car batteries.  Several springs and creeks in our area provide us and our neighbors with hydro power sources, too.  One design we built for a neighbor is based on a GMC truck alternator.  GMC alternators have a built in voltage regulator and are robust for many alternative power generation options - do a search on Google for “bicycle alternator” and you will see many clever designs for bike-power, for example.  This is one reason we keep several older model GMC trucks and a Suburban around – useful, common parts.  The alternator can be used for a 12V generator supplying up to 100 Amps of current to run AC inverters, charge batteries, or run pumps.  The neighbor’s spring is captured in a 2,000 gallon tank, and channeled off the side to ABS piping into the alternator’s turbine.  The alternator was ~$80; turbine blades are homemade and piping all from scrap on hand.

A lower cost option we used on another neighbor’s stream is my favorite.  Instead of an Alternator we used a 1200 gallon-per-hour bilge pump as a generator.  More regulation circuitry was required, but because the output was under 10 Amps, a simple solar regulator from eBay for $12 was adequate.  The smaller stream’s flow was diverted into a garden hose, fitted easily to the bilge pump’s output to run the motor as a generator.  Total setup costs (besides labor) were under $50.  These have been simple, fun, and safe ways to engage with neighbors in exploring options for remote power generation.  This setup is charging two car batteries and running 12V lighting, shortwave radio, dual-band ham radio station, and a fan in his remote shed.

Finally, one last electrical option that has worked out well for us is a water pump for our drip irrigation system.  Some of our plants require more regular watering than others, so we put in a simple drip system of tubing.  To automate it as much as possible, I used a small barrel suspended from 30 feet high to provide the water source for the tubing.  To keep the barrel full, especially in the summer months when rain is less frequent I used a small bulge-pump (12V) I had on hand to pump small amounts of water out of the livestock trough into the bucket.  I did rig up a simple microcontroller to only turn the pump on for 20 minutes each day which required more than basic electrical skills.  The pump is inexpensive and keeps the water barrel charged without any attention required.

All of these ideas are inexpensive and as simple as possible.  Just imagine what is possible with a small, microcontroller (mini computer chip) that costs less than $1.23 and very advanced sensory and computing power!  While not generally of use most people, there are options out there for your consideration.  As an engineer my emergency preparations include keeping extra microcontrollers on-hand for any number of needs.  The powerful capabilities of these modern devices are a big force multiplier for automating farm and garden tasks as well as the obvious security/OPSEC roles.  If you don’t have a working knowledge in these areas, your children may.  Many different options are available to encourage your kids, friends, etc to pursue learning if they are interested in these things, which will pay off not only in your emergency preparations, but enable them for potential engineering careers in life.

Since all of the devices mentioned are less expensive, it should encourage people to experiment with them.  Hack them, open them up, and try using them in new ways.  Kids love exploring and tearing apart things, and many of these projects have been fun for us to explore with and for the children to learn new concepts, science, and practicing putting stuff back together.  There are several photographs of these and other projects on our family blog, (Northwest Podcast).  Since these ideas are based on 12V DC they are much safer, though higher current levels must be respected.

The last note I would make regarding using electronics or technology in your preparations is to echo the warnings of the scriptures.  No gadget can replace faith and trust in the Lord.  There are significant risks and dependencies in using electronics but many of these (such as an EMP event) can be prepared for.   The scriptures warn us of trusting in the arm of flesh (Jeremiah 17:5) and of worshiping the works of man’s hands (Micah 5:13).  I believe that our culture is at great risk to this form of idolatry because of the technological blessings the Lord has given us.  Let’s use these gifts to bless the lives of our families and those around us, and put all of our trust in the Lord.


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