How To Make Induction Cooker

The induction cooking design consists of a small number of simple blocks.
The isolated power supply is obtained directly from the mains, 220 V AC 50 Hz. 15 volts are
used to supply the IGBT driver, fan, relay and feedback circuitry, while 5 volts are needed to
supply the rest of the ICs, including the MCU.
The ST7FLITE09Y0 microcontroller controls the whole process and communicates with the
user interface (buttons and display), drives the fan and the relay, receives feedback from the
cooking element (referred to in this document as “plate” for simplicity) and generates the
PWM signal to drive the IGBTs.

Schematic
Although the schematic is not very complex, this section presents the different parts as
separate topics:

    Mains, DC link and zero voltage switching
    Isolated power supply
    Power stage
    Feedbacks
    MCU pin configuration

Isolated power supply
An isolated power supply is connected immediately after the mains filtering, without passing
through the safety relay. A VIPer22A and a simple voltage regulator provide 15 and 5 volts
respectively. The power supply ground is isolated from the system ground.

Big Motor Driver TLP250

I have posted a motor controller design that is supposed to be simple, robust, cost effective, and able to handle high currents.  Above is a schematic of the first part of the design.  I will post an updated version to include a PIC to accept commands from a PC, Microcontroller, etc. and provide the direction/PWM signals to the H-bridge.  I am still working on the PCB but here is what I have done so far for review/critism.  What is not shown in the schematic are the in-line fuses for protection.

For the PIC, I use MBasic and PicBasic Pro to write the code.  This should convert easly to the BS2 and PicAxe.


 I updated the schematic again.  As suggested I changed the MOSFET driver to a TLP250 and dropped the 1K resistor across the Gate to source.
Update the schematic to show that the logic grounds are isolated from the dirty motor grounds.

Finished the PCB design.  Once boards are complete will test and post schematic and board files once any kinks are worked out.

I got the prototype boards back from the manufacture two days after I sent them off.  As you'll see below, the quality is excellent.  Tonight I populated the board and checked out functionality with a multimeter prior to testing with a motor.  I managed to get everything put together right so on to the smoke check.  I hooked up a good size motor with a lot of torque and applied power.  The motor moved in both directions and the MOSFET did not even get warm.  This test was applying full power to the motor and not PWM.  Next, I'll write some code and test functionality with PWM hooked to my Oscope so I can check the signals and see how high I can take the frequency.  I'll get around to posting some video but, in the mean time, here are some pictures of one of the finished boards.

Final Project - Ping Pong Shooter L7805CV

The Ping-Pong shooter, as its name, is able to shoot Ping-Pong balls, and the machine can simulate a real-world situation that if there is a player in front of it, it starts shooting; otherwise, it stops working

Criteria of Success
1. A machine that can shoot
2. Able to control the machine i.e. control weather the ping-pong ball will shoot or not
3. Able to control the system with a laser dependent switch


How it works:
The ping-pong shooter mainly contains three parts
1. A switch that is depends on a photoresistor and a light source(laser beam)
2. Two DC motors to shoot the balls
3. Stepping mother which acts likae a gate to control the flow of the ball


Main Component

    Photoresistor
    DC motors
    Stepping Motor (a8byj-48)
    Micro controller (89S51)
    Octal high voltage high current Darlington transistor arrays (ULN2803)
    Voltage regulator (L7805CV)



    A ULN2803 is an intergrated Circuit (IC) chip with a HIGH Voltage/High Current Darlington Transistor Array. It allows you to interface TTL signal with higher voltage/current loads
    The chip takes low level signals (operate at low voltages and low currents0 and acts as a relay of sorts itself, witching on or off a higher level signal on the opposite side.
    


    The 78xx family is commonly used in electronic circuits requiring a regulated power supply due to their ease-of-use and low cost
    I.E. 7805=5V   7812=12V
    Disadvantage: Input voltage always needs to be higher than the regulated voltage

Miscellaneous Component

    Resistor (10k ohm *2)
    Capacitor (33 pF*2,1000nF*1)
    Oscillator(12MHz*1)
    Wires
    PVC tube (2" Diameter)

Box of MOSFET BS170

I was talking to a friend about distortion boxes and the Box of Rock came up. Which got me thinking, I’d never heard one before, and Z Vex always makes good stuff. I found a schematic in the usual place. It looked like a pretty easy build.


The Box is basically two pedals in series, a distortion followed by a booster. The Box has two foot switches, The first switch engages the distortion and the second engages the booster. The controls for the distortion are Gain, Tone and Volume. The booster adds a fourth knob, Gain/Boost.

The distortion section is made of three BS170 MOSFet stages. The first stage is a SHO followed by a Marshall style high pass filter made of a 470p cap and a 470K resistor in parallel. Then come two more BS170s configured gains of approximately 51 and 15.

Next is a BMP style tone stack followed by an extra low pass filter. The low pass filter is exactly the same as used in the BSIAB II. The BSIAB II also uses the same Marshall style, 470p and 470K, high pass filter between the first two stages.

The B of R includes an SHO booster on the output. I had one of these built already so i decided not to build the stock B of R and instead build just the distortion section. I figure I can place my SHO or any other booster after it for different sounds.


I also decided to change up the tone control for a little more variety and to make this into something a little different. I had heard a few good words about the James Tone control a.k.a. Baxandall tone stack. This is a two knob type with a Bass and Treble control. A good description of this tone stack can be found here. Here’s a shorter less technical description.


Here’s an image of the James/Blaxandall tone stack. RT and RB are the Treble and Bass control. I had run into this tone control before at Freestompboxes.org in a project by forum member Mictester. It was included as part of a project called Bigmuff Plus. This was sort of a BMP on steroids. My drawing includes values for the Orange Amp tone controls and the values used in the Big Muff Plus.

Note that the Blaxandall uses the Audio taper pots for the Bass and Treble controls. These are not required but, without them the usable adjust range is bunched up at one end of the pot rotation.


I drew everything in my notebook. At this point I had the following (note this omits the extra low pass filter and volume pot):

I built everything on a breadboard to test out the idea. I tested each stage as I built it. One thing that impressed was how bad the distorted sound was without a tone stack. I shouldn’t really say “bad” as the sound wasn’t terrible. Heck, it’s distortion right, so it might sound good to somebody. What is “bad” when it comes to distortion? The sound did lack the refinement and had some extra high end hash that wasn’t helping in my opinion. Through headphone the sound was unbearable. The headphone, I’m guessing, were reproducing more high end then would come out of a guitar speaker. After adding the tone control the sound was much smoother and had a lot to recommend it.

Later I added the extra low pass filter following the tone control. This really moved the sound into the Marshall territory. This kind of extra fixed filter stage added to the end made a noticeable difference in the sound. Seems like it might be a good addition to a lot of boxes.

Originally I had planned on using the Orange tone stack. Turns out I could only find a single A1M pot. Looking over Mictester’s take on the Blaxandall, he used different resistor and cap values alone with a A470K pot for the treble control. I did happen to have an A500K pot (with detents, it clicks at each of sixteen steps). So I Decided to go with those values. Some times you have to just work with what’s available.

I drilled a box fit all the parts and wired up the standard box connections. I drew up a perf board layout which placed all of the transistors in a row. I noticed at this point that the BS170 is DGS while the 2n7000 (another MOSFET) is SGD, seems like it would possible to swap these.


I’m not the greatest at making flowery descriptions, but here goes. The sound is tight and crunchy. You can dial in a surprising amount of low end with the bass control. The bass is tight and doesn’t get muddy. It’s got a sound you would associate with Marshall amps. I’d say it does AC/DC to Van Halen. It doesn’t quite get to metal.

The added low pass along with the higher impedance tone stack cut the output noticeably. The volume needs to about 3 o’clock for unity gain. Might be good to add another transistor on the end to boost the volume. Then again maybe tinkering with the volume pot might be enough.

solated Full Duplex RS232C Interface Circuit 6N137

This is a Isolated Full Duplex RS232C Interface circuit. This circuit is used to protect PC from direct connection to hazardous voltages. Feature : isolate TxD and RxD lines from the PC serial port , baud rate of 19.2k baud, 5V supply. Component : capacitor, 1N4148 diode, LED, DB9, terminal block resistor, 6N137, CNY17-3, 74HC14. 

700W Power Amplifier with 2SC5200 & 2SA1943

700W Amplifier Adjust the amplifier power 700W looks calm, but we requirement not put out of your mind to the adjustment happening forcing transistors, the whole relating to-engagement of frequency offset. It is compulsory to change the current insurance rule which serves to guard the final transistors. Their tendency to happen allowable to keep the transistors in the SOAR characteristics. primary it was needed to evaluate all the necessary resistors and subsequently measured to verify the accuracy of the calculations, it is managed with satisfactory results. Peripheral changes required in support of it to be there able to consistently amplifier to supply power. - First you need to restore the 2k2 resistors stylish string with the LEDs on Zenerovými resistors with upper wattage. be enough 1/2W resistors, power loss next to 80V +-based 1W. - therefore was traded 1k2 resistor in the pointer resistor by the side of 620 ohms.


Which is the initial reap has doubled, so at this point is the overall gain amplifier 40 and the limit excitation is sufficient to 1V rms. - Předbudiči transistors were replaced by stronger MJE15032/33 since KF467/470 are permitted satellite dish current 20mA - by the side of the exciter output stages are used the same transistors for example the output stage. - add up to of terminals of transistors has been increased to eight pairs - It had to occur to compensate designed for the excitation level by calculation a capacitor 10pF to 47pF + 22K appendage. This led to a slight "gradual" amplifiers, but this did not affect the ensuing parameters. This power is tuned correctly in support of this type of terminal transistors 2SA1943/2SC5200.

With with the purpose of it is a least assessment next to which the amplifier operates stably exclusive of pass by the side of the rising and falling edges of the genuine. - The ultimate adjustment, the adjustment terminal current protection transistor. The SOAR transistor characteristics shows with the intention of the most allowable radio dish current once the voltage of 1.5 A is ideal in favor of cooling, so it's essentially not as much of. Therefore, the current protection is customary to 12A, single-arm. This impersonate protection SOAR transistor characteristics. curt-circuit current is regarding 6 A which is about 075A for every transistor. This is far beneath the SOAR characteristics. The mechanical design is relatively clear-cut, the transistors are placed on the two cooling profiles with a height of 66 mm, width 44mm, overall part 260mm. They are twisted contrary to each one other in this way, from the cooling tunnel. Coolers are attaching the nylon aid which allows the compilation of transistors exclusive of washers, and thus better conveying tepla.DPS amplifier next to the top of the tunnel and the transistors are soldered from the underside of PCB.

Ultimate jewel mod 4N25

My aim was to make a light up jewel (like everyone else) but this jewel had to be different. So basically I set about adding other features and the like to it.
This is what I've come up with and after you’ve read this you'll no doubt have a whole lot of similar, maybe even better ideas based on this design.

What I've ended up with is:
1. A jewel that’s glossy black when the console is off
2. Which glows blue when the console is on
3. Which glows red when there's harddrive activity

Most of these ideas are just transferred from a clear acrylic PC case mod that I did last year!



What you need:
car window tint
spray bottle
small squeegee
Wire - lots of thin gauge wire
4 x red LED’s
4 x blue LED’s
+ The resistors to go with them
For the blue/red LED’s we'll be using the 12volt power source
or if you can, try to get tri-colour LED's, they give you a better effect.
Lots of heatshrink - this is your safest bet as it makes the job incredibly easy and safe IMO
Hairdryer - to heat the heatshrink
Solder and soldering iron
Hot glue gun


Circuit
A piece of strip board
4N25 Opto-isolator
ULN2803 IC
1N4148 Diode
2 x 10K Resistor