The Challenge Suggestion Thread, - submit your suggestions HERE!

This is the Challenge Suggestion Thread:

Here you may take a look at the suggestions for the various WEC (Weekly Electronics Challenges) or BMEC (Bi-Monthly Electronic Challenges), and suggest some of your own.

The first post of this thread will be updated by me with YOUR suggestions, you can add your own in this thread. When you submit your suggestion, please also add some simple rules that should be valid for THAT suggestion only, this will be used for future reference, if we should pick YOUR suggestion at some time.

If you haven't read the rules - Do this first - Click here.

WEC Suggestions:

• Analog Timer
• Variable Pulse Generator
• Crystal Radio
• Remote Controlled Unit
• Egg Timer
• Amplitude Modulator
• Tune Generator
• Computer Interfacing
• Auto Power Off Circuit
• Tube Amplifier
• Sound Generator
• Prison Radio
• Laser Fun
• HV Sparks & Effects
• LED Pattern Generator
• Geek KeyChain
• Line Level Audio Mixer
• Anything Goes - build something weird
• Boost Converter
• Magnetic Audio Amplifier
• Isolation Transformer
• Isolated line communications
• A self-powered, miniature pulse "generator"
• Christmas Light Show

BMEC Suggestions:

• Analog Line Following Robot
• Oscilloscope Display
• Small Robot Arm
• Morse Code Transmitter and Receiver
• effects pedal
• Digital Clock
• Levitating device In progress as BMEC #6
• PIC Programming Device
• Induction Heater
• Switchmode Power Supply
• LED Frequency Meter
• Metal Detector
• Internet Radio
• 20 Watt Stereo Receiver
• Bug Zapper
• Isolated Current Sensor
• Human powered power generator

UPDATE: The competition suggestions will be RECYCLED from time to time in no particular order, meaning - if they´re fairly popular, I´ll recycle these on request or at will

Well then, I'll add a few suggestions to add to the list:

WEC suggestions:
Analog timer:
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Objective: Create an analog pulsed timer that create a pulse each second, it must be as accurate as you can make it.

Rules: You can only use simple discrete components or tubes to do this. Discrete components means no chips, no IC's, no multiple-transistor-arrays or advanced chips of any kind, not even a blinking-led with it's own on-board chip for blinking.

You also need to provide some proof of concept, preferably a you tube video (with all cables clearly visible and connected to eg. a timer or an oscilloscope - proving that your pulse is "how" accurate?

Variable Pulse Generator:
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Objective: Create an analog or digital pulse generator that is variable. Any frequency you want, any speed you want, but it must be square and regular, that means - no irregular pulses.

Rules: Discrete & Tubes & Integrated Circuits allowed, any design.

Crystal Radio:
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Objective: Build a crystal radio - cover any frequency you're capable of, and receive as many stations as you can. Components allowed - anyone, it can be anything from radio-on-a-chip, a single transistor, tubes, digital chips, anything you want to get your result.

Rules: Post a YouTube video with your results, if you have no camera, record it with a microphone and submit a mp3 or wav file with the result - if you chose to submit a wave file only, you MUST provide a schematics YOU created (or created by someone else) proving that's what you used to make it + a picture of your own submission (your radio).

Remote controlled unit:
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Objective: Build something remote controlled, it doesn't have to be wireless, but not being wireless somewhat defeats the purpose, but it's up to you how you want to design it and what you're capable of - after all - it's just an exercise in electronics and for fun. You can use any components you want to achieve this, tubes, discretes, digital chips - anything. The objective is to control something, either you turn on a LED, make something MOVE....or anything we can see or hear.

Rules: Upload a YouTube video of the final result, or show it in a picture. Other than that - no rules really.

Those all sound great, I'll add one:

Egg Timer
Monostable timer. Points for simplicity and for features(display/time scale, alert mechanism)/time range/accuracy tradeoff between the two means you should aim for a simple, accurate circuit with a decent timing range.

Amplitude modulator

Objective:

• Make a discrete square wave amplitude modulator.

Bonus points:

• Lowest component count.
• Highest speed (carrier).
• Lowest power consumption.
• Maybe something else I can't think of right now.

Rules:

• Errr, somehow prove that it actually works.
• Submit proof for each bonus point.
• No IC's or oscillators in a can or silly stuff like that is allowed.

Tune Generator.

Objective:

• Build a circuit that can output a tune through a speaker
• Tune itself can be stored any way you can think of but no flash/eeproms/etc.

Rules:

• You may use any components, but no fancy programmable IC's. A 555 timer is allowed
• Must be a proper reproducible tune, no random tones, etc.

You must be able to provide a proof of concept, a video of the circuit in action or an mp3 file and a picture. Schematic must be supplied with the entry.

Bonus points:

• Lowest component count
• Elegance of design
• A good tune of course

Oscilloscope Display

Objective:

• Create a circuit that can convert a video signal (any type) to an X-Y-Z signal (suitable for an oscilloscope).
• Display something interesting on an oscilloscope (lissajous, etc.)
• Make an oscilloscope clock.

Rules:

• Transistors, tubes, and IC's ARE allowed, but only analog or simple digital circuitry is allowed (no microcontrollers, computers, ADCs). An example of simple digital circuitry is a flip-flop, logic gate, or shift register.
• The circuit must be mostly your own design (using the example circuit from an individual IC is ok, but anything bigger is no good).
• Total component expense must be less than $50.
• Video, pictures, schematic, board design (if any), and explanation of the circuit's workings are necessary.

Bonus points:

• The more complex, the better.
• Usefulness is important.
• Be creative!

Computer Interfacing

Objective:

• Make your character LCD a monitor, so that when you type a letter from your keyboard the letter will appear directly on the LCD.
• When the LCD lines fill, the LCD should clear all the lines automatically.

Rules:

• You can use any components you want.
• Your interface should be connecting to your computer on either USB or serial port.
• You can use any programs to send the data to the port you used.
• Post a Youtube video with your results.

Abdulla

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Note: Correct any English mistake if you found in my posts, thanks.

Auto Power Off circuit

I own a couple of old battery powered multi-meters and L/C meters which have no auto power off feature. So, if I forget to turn one off after using it, I'll come back to find a dead battery. So, the challenge is to build an add-on power off circuit.


Requirements:

1. Time delay: somewhere between 1 and 10 minutes. Doesn't need to be adjustable, and doesn't need to be super accurate. The fixed time value could be set when constructed, using a fixed component value or jumper setting.

2. Power Handling: Enough to power a typical battery operated multimeter. Let's say about 100 mA just to be safe. Should also be compatible with whatever voltage the meter uses. Let's say 1.5 to 15 volts.

3. Power consumption: Should consume zero power when the device is powered down (but see item 5), and minimal power when the device is powered up.

4. Size: Should be as small as possible so that it can be fit into an existing meter case.

5. Operation:
Method A (easy): The simplest option is to have an added momentary pushbutton to turn the power on, and then the circuit will power down after the specified time elapses.

Method B (difficult): The deluxe option is to have the circuit detect current flow to the meter which tells it that the meter has been switched on, and then after the specified time elapses, it interupts power to the meter. It then keeps power interrupted until the user manually switches the meter off, at which time the circuit resets. With this second option, it would be necessary for the timer circuit to consume some power while it has the meter powered down. However, the less power consumed, the better.

6. Should not interfere with or affect the normal operation of the meter.

7. Cost and Parts Count: Do I need to say anything about this?

Please keep this thread CLEAN and to CHALLENGE Suggestions ONLY!

I will delete irrelevant posts in here in the future, this will make it easier to sift trough the suggestions over time as we pick them for each new week.

But keep them coming please.

Tube Amplifier

The obligatory tube project...

The Objective:

• Make a single ended vacuum tube audio amplifier with as few components as you can

The Rules:

• No more than 20 components (not including PSU)
• Must cost less than $50 in components
• No exotica (must be commonly available components)
• Must be battery (or low-voltage wall-wart) powered
• Only tubes (no solid state stuff except in the PSU)
• Video, pictures, schematic, board design (if any), and explanation of the amplifier's workings are necessary.

Bonus points:

• Elegance
• Low power consumption
• Decent sound

Small Robot Arm

Objective:

• Build a small robot arm can be controlling from a joystick or computer.
• The arm should move in accurate steps.
• The arm should contain 3 to 4 knuckles.

Rules:

• You can use any components you want.
• The motors should be either servo or stepper motor.
• The arm body should be plastic (to keep the low cost).
• Post a Youtube video with your results.

Abdulla

Morse Code Transmitter and Receiver

Objective:

• Build a Morse code transmitter and receiver

Rules:

• Must transmit over radio
• Any modulation scheme is OK
• No radios-in-a-chip or microcontrollers or anything like that
• Should have a decent range (across a street, for example)
• Component cost must be less than $50
• Video, pictures, schematic, board design (if any), and explanation of the transmitter and receiver's workings are necessary.

Bonus points:

• Small size
• Reliability
• Elegance

Make an electronic sound producing device using the fewest possible components.
Anything goes, except the sound has to come from a speaker or piezo disc & must be self sustaining.
Points for the fewest components, most power output, closest waveform to a pure sine wave.
Special prize for the most irritating sound, if you cannot, or don't want to, achieve a reasonable sine wave.

Since we do seem to have a few guitarists in the forum at various levels of electronic development.
the Tone Bender special.
Objective:
build an effects pedal be it distortion, reverb or any other form of audio modification or enhancement.

Rules:
It must work, Schematics and sound clips must be provided.
It must make either proper, or improper but effective use of at least 1 LED.
All parts allowed.

Bonus ... creative misuse of parts to provable effect.

Line Following Robot (with a twist)

Objective:

• Robot must follow line in a closed loop course (any shape except a circle).

Rules:

• Robot must utilise a steering mechanism independant of the drive wheels. Solenoid(s), steering motor(s), or other steerig mechanisms are allowed. Steering via drive wheels (brake/skid steering) is NOT allowed.
• Robot must be fully supported by wheels (i.e. nothing allowed to drag on course surface).
• Discrete components only. No ICs.
• Proof of design success required (video preferred).

Just a thought.

Prison Radio

Objective:

• Build an AM radio

Rules:

• Only supplies that would be available in a prison are allowed (like that thread that JoOngle did a while ago)
• Must have adjustable channel (it needs to be able to tune to multiple frequencies)
• Video, pictures, schematic, and explanation of the radio's workings are necessary.

Bonus points:

• FM capability
• Amplification
• Adjustable volume
• Good reception
• Simplicity

Laser Fun

Objective:

• Make a laser setup, make it do something interesting.

Rules:

• You can use any commercial laser you want
• You can use laser diodes too
• The setup must do something, maybe an alarm, maybe a mosquito killer, sensor, light-show.
• You can use any components you want for this, a computer is allowed too
• Building your own controller is encouraged

Digital Clock


Objective:

• Build a digital Clock with (1-4) switchs to set the time.

Rules:

• You can use any components you want.
• The display should be characters LCD, or Clock LED Display.
• Post a Youtube video with your results.

Abdulla

Levitating Device

Objective:

• Build a levitating device

Rules:

• Must be levitating on it's own, no strings or wires attached
• You can use any components you wish
• The device must be operated by electricity, not magnetism alone
• No computer fakery or special effects
• You may use both analog and digital components, computers too
• Video proof of a functioning device must be provided

HV Sparks & Effects

Objective:

• Create a mad-science device that sparks, fizzes or produces ligthning like effects, arches or otherwise

Rules:

• Must create some kind of effect that lights up
• Must be High-Voltage
• You are free to use any components, tubes, transformers, even ready made HV-generators

Geek chain.
from a thread about a pocket sized laptop someone was drooling over.
the goal is to build a key chain sized device that flaunts your geekhood.
it must fit in a pocket and perform any sort of function ...
micro controllers will likely be used so USB is good for bonus points

I think we could incrementally build stereo receivers through a series of WECs Id hold off on it for now untill things get moving a little more fluidly though.

first wec .. power amp
second wec tone controls / EQ's
third wec signal switching
fourth wec .. making them all fight nice in the same cab.
all wecs should be wide open all components in since it would have a real world useful outcome ... who couldn't benefit from one of these at the WEC bench?

How about some useful bench equipment? The simpler stuff might appeal to those with less experience.

- A signal generator that produces variable frequency square, sine, triangle and/or sawtooth waves.

- A variable voltage-regulating module than can be used with any DC power supply.

- A variable current-limiting module than can be used with any DC power supply.

- A variable PWM module than can be used with any DC power supply.

- A low current 300V-500V voltage supply (for testing MOVs, etc.).

- A simple multi-purpose bench amplifier.

- A minimal current audible/visible (buzzer/LED) continuity tester.

Just a few thoughts.

A capacitance meter can be surprisingly easy to build.

An LC meter is a bit harder...

PIC Programming Device

Object:

• Build a small programmer for any PIC series 12,16,.....

Rules:

• The programmer should work on either serial or USB port.
• Post a picture and video with your results.

Abdulla

Line Level Audio Mixer

Objective:

• Design & build a line level mixer for headphones/headset.

Rules:

• Must have at least two line level inputs.
• Must have a single output (to headphones/headset).
• Must be an active design.
• Discrete components only.
• As usual proof of working design required: Video (must have audio) of working circuit or schematics with detailed explanation.