EMF Meter Comparison (ED88T, ED78S, Trifield 100XE)

After searching for the right EMF meter for my home, I decided to buy the Cornet ED88T. On this post you will find why.

These are four types of EMFs that you want to measure in areas where you spend a significant amount of time:

  1. Microwave Radiation
    • Sources: wireless technology like Wi-Fi routers, cell towers, cordless phones and “smart” meters
  2. Magnetic Fields
    • Sources: power lines, improper home wiring and appliances
    • Health: They decrease the immune system and are known to be carcinogenic3
  3. Electric Fields
    • Sources: unshielded electrical wiring
    • Health: They rob you of a good night’s sleep3
  4. Dirty Electricity
    • DE are the frequencies that travel on your home wiring from things like solar power inverters, florescent lighting, dimmer switches and wireless “smart” meters)
EMF type Cornet ED88T Cornet ED78S Trifield 100XE
Microwave Radiation  Yes  Yes  Yes, but not accurate2
Magnetic Fields  Yes  Yes  Yes
Electric Fields   Yes, but the scale is not ideal1  No Yes, but the scale is not ideal2
Dirty Electricity  No  No  No

Once you have the ED88T, you can watch this video to learn how to use it and you’ll probably wonder what the safe maximums are for all the readings:

EMF type Safe Max3 Safe Max in Cornet ED88T screen readings
Microwave Radiation  100 (day) 10 (sleep) microWatts/squared meters (uW/m2)  0.1000(day), 0.0100 (sleep) miliWatts/squared meters (mW/m2)
Magnetic Fields 1.0 milliGauss (mG)  00.10 microTesla (uT)
Electric Fields  Less than 10 V/m  0010. V/M
Dirty Electricity 25-50 Graham-Stetzer Units

Here are some of the readings I’ve collected.

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Building your own Annoy-a-tron with an ATtiny85

The annoy-a-tron is a little device that makes a small beep every X minutes. If you hide it well enough in a co-worker’s cube, it will drive him/her insane and will do almost anything to find it.

The annoy-a-tron is currently out of stock at ThinkGeek and I really wanted to prank someone at the office with it. So I did some research and decided to build one.

I decided to go with the ATtiny85 because I enjoy coding more than I do soldering. Instead of buying a 555 timer chip with resistors, capacitors, etc. like they are doing here, I just need to program the chip, wire up a battery and a speaker. I chose the ATtiny85 over the Arduino hardware because the ATtiny is cheaper and draws less power.

The final product looks like this:

20150621_223628

And the software I put together makes a beep of customizeable tone frequency and length at random time intervals.

These are the parts you need to build the circuit:

The ATtiny85 is cheaper if you buy it in bigger quantities, I regret not buying more just so I can have different programs (different random intervals, tone, and tone length) loaded on the chips ready to go. SparkFun doesn’t have the best prices so look around if you will buy in bulk. I trust SparkFun and that’s why I bought most things there though.

You need a programming board to program the ATtiny85. I chose the Tiny AVS Programmer instead of the official one because I wanted to try out the Arduino IDE. To set up the IDE with the programmer, just follow the programmer’s hookup guide.

The Circuit:

The circuit is very straight forward. You just wire:

  • The positive end of the battery holder to the positive pin on the ATtiny85 (the solder tail).
  • The negative end of the battery holder to:
    • The negative pin on the ATtiny85
    • The negative pin on the piezo speaker
  • The chosen out pin (I chose pin 1) of the ATtiny85 to the positive end of the piezo speaker.

20150621_223603

The Program:

I used the Arduino IDE (set up with the Tiny AVR Programmer Hookup guide) to program the ATtiny85.

Click this link to get the source code of program I loaded on the ATtiny85.

The program was deeply inspired by TinyTone to generate the tones and millionOhms to preserve power by getting the ATtiny85 to go to sleep.

I found that testing the program out takes a long time since you have to actually wait and see how the chip behaves. The program works like I want it to but I still have some questions that I’d like to ask an Arduino IDE (c++) expert or need a good amount of time to test out:

  • are the #include statements optional?
  • are the #define statements actually setting a variable or are they optional?

Testing those things would take time since removing them might not make compilation break but it might make the ATtiny85 not go to sleep properly and use more battery than expected. So I would have to see how long the battery lasts to really know if it is sleeping properly or measure the current being used by the ATtiny85 with an ampmeter.

Well, I hope you have fun with the ATtiny85! I’ve tried it with a couple of beta victims and I’m ready for a real one tomorrow.

Unlocking your Verizon phone

I currently own a Verizon HTC Incredible 2 cell phone.

I’m happy with Verizon (they’re the only ones that have good signal inside my house). But when I go outside the USA (I go to Guatemala often), I want to be able to switch the SIM card to one that works with a local mobile service providers. Otherwise I would have to use roaming with Verizon and that is ridiculously expensive.

I gave Verizon a call and they quickly gave me the  “unlock” code for me to enter in my phone. After entering the code, the phone was immediately unlocked! They only made me agree to a very obvious agreement that if I stick another SIM card in there I acknowledged that I was no longer using the Verizon service and Verizon could would not support me while I had that third party SIM card in my phone. But if I then switched back to my Verizon SIM card and ran my phone in CDMA (or Global) mode, I would be supported again.

And one more thing, Verizon uses CDMA. SIM cards are used for GSM. So I tried removing my Verizon SIM card from my phone and I was still able to get Verizon service. Nice to know.

I then stuck a SIM card from a friend that uses T-mobile and switched my Incredible’s mode to GSM, I could make and receive calls as him. Very cool.