1. Post #121
    www.bff-hab.de
    Dennab
    February 2009
    7,832 Posts
    Make sure to put a heatsink with a fan on it on the hot side.
    Reply With Quote Edit / Delete Windows 7 Germany Show Events

  2. Post #122
    XeNo's Avatar
    August 2006
    98 Posts
    I'm joining this competition in which we have to make an automatic line following robot(as has been done loadsa times)

    Everything should work great but we don't know what motors we should get.
    The robot won't weigh more than 1kg(probably a lot less) and it should be able to go atleast 1m/s

    We don't really know how much torque and rpm it needs though so if anyone could help us, that'd be great

    We need 2 motors and were thinking of geared dc motors http://be02.rs-online.com/web/c/auto...t-option=Prijs

    But we don't want to waste money on motors which are too powerful so could someone give us an example of a motor which would suit our needs, thanks
    Reply With Quote Edit / Delete Windows 7 Belgium Show Events

  3. Post #123
    LoneWolf_Recon's Avatar
    May 2011
    1,742 Posts
    Reply With Quote Edit / Delete Windows XP United States Show Events Friendly Friendly x 1 (list)

  4. Post #124
    OrYgin's Avatar
    November 2007
    751 Posts
    Finally got around buying an arduino. Hoping sparkfun delivers quickly.
    Reply With Quote Edit / Delete Windows 7 Belgium Show Events

  5. Post #125
    Gold Member
    Tw34k's Avatar
    January 2012
    680 Posts
    Finally got around buying an arduino. Hoping sparkfun delivers quickly.
    Yeah, they ship pretty quickly. Shoulda bought just the AT328 and built your own arduino :P
    Reply With Quote Edit / Delete Windows 7 United States Show Events Dumb Dumb x 2 (list)

  6. Post #126
    OrYgin's Avatar
    November 2007
    751 Posts
    Yeah, they ship pretty quickly. Shoulda bought just the AT328 and built your own arduino :P
    I don't think I could've done this :p

    However, I'm not in the US, so maybe it'll slow down.
    Reply With Quote Edit / Delete Windows 7 Belgium Show Events

  7. Post #127
    Gold Member
    Tw34k's Avatar
    January 2012
    680 Posts
    Honestly all a arduino is, is just a breakout board with a power regulator and usb-serial interface. The last of witch isn't always even needed.
    Reply With Quote Edit / Delete Windows 7 United States Show Events Late Late x 1Informative Informative x 1 (list)

  8. Post #128
    Gold Member
    Zero-Point's Avatar
    March 2006
    7,435 Posts
    Honestly all a arduino is, is just a breakout board with a power regulator and usb-serial interface. The last of witch isn't always even needed.
    Arduino is more of an improvement on the development side, kinda like a DirectX for microcontrollers (more specifically ATMega chips).
    Reply With Quote Edit / Delete Windows 7 United States Show Events

  9. Post #129
    Gold Member
    VistaPOWA's Avatar
    October 2008
    8,370 Posts
    Yeah, they ship pretty quickly. Shoulda bought just the AT328 and built your own arduino :P
    You do that when you want to finalize a design. Programming an AT328 takes you an AVR programmer to burn in the Arduino code, an Arduino as ISP then you can only re-program it using an Arduino.
    Reply With Quote Edit / Delete Windows 7 Hungary Show Events

  10. Post #130
    www.bff-hab.de
    Dennab
    February 2009
    7,832 Posts
    I personally believe that the arduino is a great stepping stone for beginners of electrical engineering. It allows you to very easily get started with some simple projects without setting up too much hard- or software. Even further down the line it can be used as a good prototyping platform, but eventually everybody who wants more will grow away from the arduino and move on to AVRs.

    For artists who just need a simple tool that works, the arduino is perfect and exactly what they need. They don't want any hassle to get their art done, they just want it to work.
    Just imagine if you wanted to get into sculpting, but you first have to make the hammer and chisel yourself, which would turn off the most of us.

    Anyways, my point being: If you really want to advance further into electronics, you'll eventually have to ditch arduino and get your hands dirty with AVRs. The change will be very hard, because all of the sudden you have to do everything arduino did for you before, but you get to see what actually happens and you can even make things operate differently (The ADC or using Pins is a good example for that).

    I only use the arduino for really really quick prototyping and as a power supply due to it's convenient power-barrel-jack with the broken Vin pin, that allows me to access a wallwart without having to fiddle around with the barrel-jack.
    Reply With Quote Edit / Delete Windows 7 Germany Show Events Agree Agree x 2 (list)

  11. Post #131
    SubbyV-2's Avatar
    January 2011
    273 Posts
    110VAC. I've got a 3A peltier wafer lying around and I'd like to make a tiny fridge out of it.
    Would an atx power supply not suffice?

    Ddrl, you always have something against atx power supplies, explain the problem with them in an intelligent form please?
    Reply With Quote Edit / Delete Windows 7 Australia Show Events Dumb Dumb x 1 (list)

  12. Post #132
    www.bff-hab.de
    Dennab
    February 2009
    7,832 Posts
    When I powered my peltier, I found out it was to be powered at exactly 15V and would draw 6A. So I bought a 15V 7A Laptop charger and used that to power the peltier! I got ice forming on it, but I probably would've achieved better results with a bigger heatsink and fan.
    Reply With Quote Edit / Delete Windows 7 Germany Show Events Winner Winner x 1 (list)

  13. Post #133
    SubbyV-2's Avatar
    January 2011
    273 Posts
    Oh god double post, 110vac to 12vdc at 4a inst easy

    Might order myself a peltier to play with, what kind of wattage can a old amd cpu cooler put up with?
    Reply With Quote Edit / Delete Windows 7 Australia Show Events

  14. Post #134
    RISC MASTER RACE.
    MIPS's Avatar
    August 2010
    7,095 Posts
    I ahd a friend who glued a peltier tot he bottom of his coffee mug to act as a warmer.
    It didn't work because the mug insulated it and when he tried tot ake it off he split it in two.
    Reply With Quote Edit / Delete Windows XP Canada Show Events Funny Funny x 6 (list)

  15. Post #135
    SubbyV-2's Avatar
    January 2011
    273 Posts
    Got my tube! now just gotta work out a 250Vdc boost converter, 6.3v regulator, 12v to -10v, and non inverting amplifier
    Reply With Quote Edit / Delete Windows 7 Australia Show Events

  16. Post #136
    www.bff-hab.de
    Dennab
    February 2009
    7,832 Posts
    I ahd a friend who glued a peltier tot he bottom of his coffee mug to act as a warmer.
    It didn't work because the mug insulated it and when he tried tot ake it off he split it in two.
    Yes, peltiers without a heatsink self destruct within seconds.
    Reply With Quote Edit / Delete Windows 7 Germany Show Events

  17. Post #137
    Gold Member
    Zero-Point's Avatar
    March 2006
    7,435 Posts
    Would an atx power supply not suffice?

    Ddrl, you always have something against atx power supplies, explain the problem with them in an intelligent form please?
    Nah, I want this fridge to be just big enough to put a water bottle in it. Would like it to be a complete unit but I guess I could settle for a brick PSU. :/
    I've powered it with an ATX supply before, was pretty fun. Even put it on the CPU in my mineral oil PC. Kept it cool... At idle. I knew it wouldn't do much at load, I was just curious is all.
    Reply With Quote Edit / Delete Windows 7 United States Show Events

  18. Post #138
    RISC MASTER RACE.
    MIPS's Avatar
    August 2010
    7,095 Posts
    The rest of my day was spent learning about what has been done with the Mattel Juice Box since I last owned one in 2005.



    Seven years later, here I am with one and in that time the systems have been totally documented and NOTHING HAS BEEN FUCKING DONE WITH IT.
    I don't get it. Here you have something that can play fair bitrate audio and display low resolution pictures and video and so far the most hardcore hacks done with it was to modify the loaded linux distro and make an XD memory adapter. Nobody even messed with how to package your own videos.
    I'm tempted to mess with it but it seems that everything you can do with it has already been done so is there really much of a point?
    Reply With Quote Edit / Delete Windows XP Canada Show Events

  19. Post #139
    SubbyV-2's Avatar
    January 2011
    273 Posts
    Anyone know how to get a clock out of a crystal?
    Reply With Quote Edit / Delete Windows 7 Australia Show Events

  20. Post #140
    www.bff-hab.de
    Dennab
    February 2009
    7,832 Posts
    Anyone know how to get a clock out of a crystal?
    http://www.z80.info/uexosc.htm
    Reply With Quote Edit / Delete Windows 7 Germany Show Events

  21. Post #141
    SubbyV-2's Avatar
    January 2011
    273 Posts
    thanks, but i realized i'll never get a 3KHz crystal.
    Reply With Quote Edit / Delete Windows 7 Australia Show Events Funny Funny x 1 (list)

  22. Post #142
    Aw_Hell's Avatar
    July 2009
    1,158 Posts
    thanks, but i realized i'll never get a 3KHz crystal.
    You should try a real time clock IC, they range from small and simple:

    http://search.digikey.com/us/en/prod...55ED-ND/805852

    To big and fancy:

    http://search.digikey.com/us/en/prod...55ED-ND/805852
    Reply With Quote Edit / Delete Windows 7 United States Show Events Disagree Disagree x 2 (list)

  23. Post #143
    LoneWolf_Recon's Avatar
    May 2011
    1,742 Posts
    I've finished the power supply for the transmitter, and have completed roughly half of the main transmitter board. But I broke a pin on one of the variable caps so I'm outta luck right now :P
    Reply With Quote Edit / Delete Windows XP United States Show Events

  24. Post #144
    Gold Member
    ddrl46's Avatar
    October 2007
    3,681 Posts
    You should try a real time clock IC, they range from small and simple:

    http://search.digikey.com/us/en/prod...55ED-ND/805852

    To big and fancy:

    http://search.digikey.com/us/en/prod...55ED-ND/805852
    He was talking about a clock signal not a time keeping chip.
    Reply With Quote Edit / Delete Netherlands Show Events Agree Agree x 1 (list)

  25. Post #145
    SubbyV-2's Avatar
    January 2011
    273 Posts
    You should try a real time clock IC, they range from small and simple:

    http://search.digikey.com/us/en/prod...55ED-ND/805852

    To big and fancy:

    http://search.digikey.com/us/en/prod...55ED-ND/805852
    I didnt know these puts out clocks?
    Reply With Quote Edit / Delete Windows 7 Australia Show Events Dumb Dumb x 2Late Late x 1Funny Funny x 1 (list)

  26. Post #146
    Gold Member
    Chryseus's Avatar
    February 2009
    2,426 Posts
    I didnt know these puts out clocks?
    They don't.

    Also MIT is doing a free online version of their analog electronics course.
    https://6002x.mitx.mit.edu/
    It starts March 5th.
    Reply With Quote Edit / Delete Windows 7 United Kingdom Show Events Winner Winner x 2 (list)

  27. Post #147
    Gold Member
    ddrl46's Avatar
    October 2007
    3,681 Posts
    You might remember this one from the first thread, replaced a 3 to 8 decoder and it works again:

    Reply With Quote Edit / Delete Windows 7 Netherlands Show Events Winner Winner x 2Artistic Artistic x 1 (list)

  28. Post #148
    chipset's Avatar
    November 2010
    2,262 Posts
    You might remember this one from the first thread, replaced a 3 to 8 decoder and it works again:

    I don't, what is it?
    Reply With Quote Edit / Delete Windows 7 Sweden Show Events

  29. Post #149
    Gold Member
    ddrl46's Avatar
    October 2007
    3,681 Posts
    I don't, what is it?
    Intel 8085 system design kit.
    Reply With Quote Edit / Delete Windows 7 Netherlands Show Events

  30. Post #150
    Gold Member
    Chryseus's Avatar
    February 2009
    2,426 Posts
    Made a quick op-amp relaxation oscillator for Subby.



    Slight modification, add 47uF from the virtual ground to the circuit ground, this cuts out quite a bit of noise.
    There seems to be a step response on the rising and falling edge about 8us long, not exactly sure what is causing it.
    Actually thinking about it, it could be the result of parasitic capacitance and inductance since it seems to get worse with increasing frequency.
    Anyway it's not a problem unless you want a fast clean rise and fall, you could put it into another op-amp and use that as a simple comparator to get a clean output.

    Changed the non-inverting feedback resistor to 100k, that seems to have greatly reduced any step but I'm still not completely sure as to how.
    Reply With Quote Edit / Delete Windows 7 United Kingdom Show Events Useful Useful x 2Funny Funny x 1Agree Agree x 1 (list)

  31. Post #151
    www.bff-hab.de
    Dennab
    February 2009
    7,832 Posts
    A fresh canvas

    Reply With Quote Edit / Delete Windows 7 Germany Show Events Disagree Disagree x 2Agree Agree x 1Optimistic Optimistic x 1 (list)

  32. Post #152
    Tobba.'s Avatar
    February 2012
    17 Posts
    I was needing some high voltage for something, and I couldent find my brick sized HV transformer (how the fuck did I misplace this)

    So as a quick and dirty soloution I ripped a flyback transformer out of an old CRT
    Now to figure out the pinout of this
    Reply With Quote Edit / Delete Windows 7 Sweden Show Events

  33. Post #153
    Chezburger's Avatar
    February 2009
    724 Posts
    A fresh canvas

    Your puny canvasses are nothing compared to my sheets of uncut pcb
    Reply With Quote Edit / Delete Windows Vista Netherlands Show Events Funny Funny x 5Dumb Dumb x 2Informative Informative x 1 (list)

  34. Post #154
    LoneWolf_Recon's Avatar
    May 2011
    1,742 Posts
    Oh do you mean this?
    Reply With Quote Edit / Delete Windows XP United States Show Events

  35. Post #155
    Gold Member
    Chryseus's Avatar
    February 2009
    2,426 Posts
    Just finished shopping, bought:

    100 UV LEDs
    Tweezers set from dealextreme
    Alcohol dispenser
    Small flux container bottle
    Solid rosin flux (for ultra cheap homebrew flux)
    Samsung ML-1865 mono laser printer
    Pack of ten 0.8mm drill bits
    1L of isopropanol
    500gr of sodium metasilicate pentahydrate
    1kg of ferric chloride hexahydrate
    two 100ml cans of positive spray photoresist
    five single sided copper clad boards
    20m roll of 90gsm tracing paper

    All for 115, pretty good I think.
    Time to get making them PCBs :-D
    Reply With Quote Edit / Delete Windows 7 United Kingdom Show Events Useful Useful x 1Winner Winner x 1 (list)

  36. Post #156
    www.bff-hab.de
    Dennab
    February 2009
    7,832 Posts
    WIP

    Reply With Quote Edit / Delete Windows 7 Germany Show Events Optimistic Optimistic x 1 (list)

  37. Post #157
    LoneWolf_Recon's Avatar
    May 2011
    1,742 Posts
    What's on the blue board? Is that an Analog Devices' IC?
    Reply With Quote Edit / Delete Windows XP United States Show Events

  38. Post #158
    Gold Member
    ddrl46's Avatar
    October 2007
    3,681 Posts
    What's on the blue board? Is that an Analog Devices' IC?
    DDS func gen.
    Reply With Quote Edit / Delete Netherlands Show Events Winner Winner x 1 (list)

  39. Post #159
    TVC

    April 2010
    300 Posts
    Anyone know where I can get a good hobbyist Smartcard Reader/Writer, all I find a commercial ones which I'm afraid won't give me full access to the serial interface.
    Reply With Quote Edit / Delete Windows 7 Australia Show Events Funny Funny x 1 (list)

  40. Post #160
    www.bff-hab.de
    Dennab
    February 2009
    7,832 Posts
    What's on the blue board? Is that an Analog Devices' IC?
    It's a board for the AD9850, it can generate sinewaves from 0 to 125 MHz with a precision of 0.0291 Hz/lsb.

    Edited:

    Anyone know where I can get a good hobbyist Smartcard Reader/Writer, all I find a commercial ones which I'm afraid won't give me full access to the serial interface.
    Sparkfun carries one, but of course it's pretty expensive.
    Reply With Quote Edit / Delete Windows 7 Germany Show Events Winner Winner x 1 (list)