Electronic Hobbyist

For your first High Voltage Project, I highly recommend the Flyback Transformer and Driver. The Flyback Transformer (depending on size) can drive an output of up to 40kV! It all depends on the Amp's you are feeding through your Primary, and the voltage of your Power Supply. I was getting 1.5cm Spark's out of mine with a 12V 850ma Power supply! A Flyback Transformer likes to run at a 20kHZ pulsed Power Supply. So to make it easy, I will give you tips and the circuit to build yours from!

(An example of a brand new Flyback Transformer. Image taken off of www.electronicrepairguide.com)

Flyback Transformers are most commonly found out of old CRT Computer Monitors and CRT TV's. I found mine out of an old TV circuit board. If you can't find one, go to your local TV repair guy and ask for a Flyback Transformer. He will most likely have one lying around. I myself have about 10, half I have gotten from my TV repair guy.

THE CIRCUIT
There are several circuits that you can drive your Flyback with. My first Circuit was a 555 Timer wired up to run at 20kHZ and that powered a N channel MOSFET. It is very technical, so I reccomend the ZVS Flyback Transformer Driver Circuit. With this Driver, you can put up to 50VDC and Several Amps through it!  The schematic is very simple, along with a bill of parts. The MOSFET's can be difficult to get, but if you look around you should be able to find them.



(www.tesladownunder.com You can also find the original image http://tesladownunder.com/Flyback_driverAndrineri.jpg if you cannot read the above image)

Once you build your Circuit, it is time to wind your Primary!

PUT A HEATSINK ON EACH IRFP250's TO PREVENT BURNING THEM UP!!!!!!!

Once you are prepared, hook up your Flyback and your Circuit to power. If nothing happens, make sure you have everything correct. Now it is time to find the Other Secondary pin. (the Secondaries are one of the pins in the flyback, and the thick wire coming out of the top, with the little rubber cone on it. I suggest taking it off and just having a bare wire lead. Hook up a stick to it for safety). Take the one secondary lead and drag it across all the pins safely. What ever pin pulls the longest arc, mark it and there you go! you now have a working Flyback Transformer! I will get pictures on here soon!

This is a fun and simple robot, using 555 timer's in Astable mode. The CdS cells set's the frequency, in turn making the robot turn by PWM (Pulse Width Modulation). It is slow, but very fun and satisfying to watch over a period of time. This is a coustom circuit that I designed to demonstrate the ease of interfacing a 555 to control a robot. To make it seek dark, just reverse what sides the motor's are on (A trick I learned from David Cook)

UPDATE!

I Worked with the Pummer, and I finally got a good one working. It is different than any BEAM Pummer, but it is fun to look at, and simple. The large capacitor makes the LED fade in and eventually be quite bright.

My easiest robot, Macaroni is a obstacle avoiding robot using 2 micro switches taken out of a mouse. It is really easy and I would definately suggest it as a simple or first robot. Email me if you want some switches for free.

Parts Required:

• 2 SPDT Micro Switches
• 2 Motors
• 3V Batteries (or your battery voltage in half, look at schematic)
• Some kind of body
• Battery holder
• Wire

BEAM stands for the following things (most commonly)

• B: Biology
• E: Electronics
• A: Aesthetics
• M: Mechanics

My personal Variant is:

• B: Building
• E: Easy
• A: Autonomous
• M: Machines

Some other wierd less common ones are:

• B: Building
• E: Evil
• A: Apocalyptic
• M: Machines

Well, ok maybe the last one was a bit made up, but they all have one thing in common: The Nv Neuron. The Nv Neuron is a very easy and basic circuit created by the amazing and one and only Mark Tilden, the "Big God" of BEAM Robotics. The Nv Neuron may appear to be nonsense, and complete gibberish, but it actually is a incredible and amazing circuit. In a short Sense, the Nv Neuron is a Capacitor, a Resistor, and a Inverter.

 

(Courtesy of www.solarbotics.net, the best BEAM website out there, just dont die on us!)

The capacitor value can range from 0.1uf to 0.33 uf, and the resistor can range from 1M to 4M ohm, but it you experiment with the following formula you can substitute other values as well:

R*C

    R= Resistance in Ohms
    C= Capacitance in Farads

For example, if you want the same timing as the 0.1uf capacitor and the 1M ohm Resistor, you could use a 1uf capacitor and a 100K Ohm Resistor. More examples Follow:

Resistor Value (in ohms)	Capacitor Value (in microfarads)
1M	0.1uf
100K	1uf
10K	10uf
1K	100uf

I personally prefer the 1uf and the 100K setup, only because It is more available (for me)

You can also hook them up to each other to create some pretty cool robots, such as Walkers (Solarbotics.net reference) and many others.

The Bicore:

The Quadcore:

Now that you have the basic Idea, you could apply what you have learned to try these out. Attach a Resistor to the output of each Inverter to see what it is doing.

 

I am currently working on BEAM robots, which will soon be under a BEAM Robotics Link in the Status bar on the side.

A huge thanks for www.solarbotics.net, the best website for BEAM ever! Tons of links and all sorts of awesome things on there just waiting to be looked at. This is merely a glimpse as what you could do with this BEAM technology. Please check it out!

 

 

I recently built the circuit on Dick Cappels web site (scroll to "rusty Nail Night Light").  These are plans for the Mini 1.5V Voltage booster.  It works great and I suggest using a 1000pf cap.

The circuit is extremely basic, using only 1 capacitor, 1 resistor, 1 LED, and 1 NPN 2222A transistor. It also requires 1.2V to 1.5V input (a AA battery or button cell). It is a very easy circuit, fun for anybody starting electronics. It is based off a inductor, or ferromagnetic core (in my case, a bolt). It MUST be magnetic, or it would do nothing except look like a coil of wire around a bolt. Mine happened to fit perfectly into a small AA battery holder, making it very compact and super sweet looking.

Parts required:
1x 1000pf to 0.1uf capacitor ( In mine, I used a 3300pf)
1x 1k resistor
1x red LED
1x NPN PN2222A Transistor
1.2-1.5 Volt Battery
Some thin insulation wire (24 gauge with thin insulation wire, such as Cat5e wire)
A Bolt slightly shorter than a AA battery (if you want it to fit inside a AA battery holder)
Electricians tape

Tools Required
Soldering Iron
Wire cutter/stripper
Solder
Nippy cutters
Dremel (for cutting the hole in the case, my T13/4 LED fit perfectly snug in the case screw holder)
Pliers

STEP 1. Take the Transistor and Bend the Emitter and Collector 90 degrees to opposide sides (facing away from the Base). Take the LED and push the Leads together so they are close but not touching each other. Then insert the Transistor between the leads (cathode to emitter and anode to collector) and push all the way through so it is almost laying on the transistor's labeled side. Solder and clip the LED leads.

STEP 2. Spread the capacitor's leads apart and put the resistor inbetween them so the resistor is in parallel with the capacitor. Make sure they are as close to eachother as possible. Clip the capacitor's leads and solder one side to the base. Make sure you have everything as compact as possible.

STEP 3. Take your bolt and some long wire and start wrapping it tightly around the bolt. Make sure it is uniform and neat, and it will look good. Have it end at the other side of the bolt (like a electromagnet nail). Take the other wire and wrap that round the wire and bolt too. End it on the opposide side you started. Solder 2 different sides together, and solder one of the remaining 2 sides to the capacitor resistor, and the other to the collector of the transistor.




The above image is the circuit when finished. I substituted the 2700pf cap with a 0.1uf capacitor and another with a 3300pf, but you can use anything within 0.1uf to 1000pf capacitor.

finish the circuit and you are done!

This is mine (below)

Mine works excellent and it looks awesome. Hope you have luck with yours.
If you want to have fun with your circuit, change around the capacitance of the cap on it.

Here's a simple lie detector that can be built in a few minutes, but can be incredibly useful when you want to know if someone is really telling you the truth. It is not as sophisticated as the ones the professionals use, but it works. It works by measuring skin resistance, which goes down when you lie.

• R1 1 33K 1/4W Resistor
  R2 1 5K Pot
  R3 1 1.5K 1/4W Resistor
  C1 1 1uF 16V Electrolytic Capacitor
  Q1 1 2N3565 NPN Transistor
  M1 1 0-1 mA Analog Meter
  MISC 1 Case, Wire, Electrodes (See Notes)

Notes
1. The electrodes can be alligator clips (although they can be painful), electrode pads (like the type they use in the hospital), or just wires and tape.

2. To use the circuit, attach the electrodes to the back of the subjects hand, about 1 inch apart. Then, adjust the meter for a reading of 0. Ask the questions. You know the subject is lying when the meter changes.