[url]http://thecubeserver.com/tests/arduino/rc/[/url]
The RC car is back up! Remember: it probably can't go up the chimney :v:
I stuck a metal pole on it and wrapped the antenna around it to boost the range, too. I'm using a slightly worse camera, but this means I can leave it on most of the day. If there are long delays in the stream, refresh the page and as soon as it loads, press play on the video stream (that seems to work for some reason)
Anyway, have fun!
[img]http://i48.tinypic.com/351xvv4.png[/img]
That is all I see :(
Hmmmmmmmmmm
Do you have flash installed and enabled?
What do you see here? : [url]http://www.ustream.tv/channel/ircc[/url]
I couldnt even move the car even after clicking on the java applet
[QUOTE=SubbyV-2;36325176]I couldnt even move the car even after clicking on the java applet[/QUOTE]
Were you using WASD? Or were you trying the arrow keys?
[QUOTE=Trumple;36325186]Were you using WASD? Or were you trying the arrow keys?[/QUOTE]
WASD
Other ustream streams work for me, yours is just black though:
[img]http://i46.tinypic.com/ne4uu.png[/img]
Yeah I was adding some protection to the car :v:
Back on now
Put the car in the chimney, drove it back down, car crashed under bed.
Very nice, it's really fun to try to wreck your room!
[QUOTE=SEKCobra;36325623]Put the car in the chimney, drove it back down, car crashed under bed.[/QUOTE]
Yeah came back and found it upside down
I still have no idea how you managed that
Well you said we can't drive it up the chimney so i did that and when it came back down it was going somewhat fast.
I think it's upside-down again. It is quite awesome though!
One thing that might need a bit of a poke is waiting a little longer between someone loading the page and getting control. Both times that I've loaded it, it dropped me into the driver's seat right as ustream started an advertisement, meaning I could drive, but couldn't see.
[QUOTE=Lapsus;36326501]I think it's upside-down again. It is quite awesome though!
One thing that might need a bit of a poke is waiting a little longer between someone loading the page and getting control. Both times that I've loaded it, it dropped me into the driver's seat right as ustream started an advertisement, meaning I could drive, but couldn't see.[/QUOTE]
Ah yes, I'll bump it up to 30 seconds of initial waiting time
[editline]14th June 2012[/editline]
Thanks for the compliment!
So, this is going way back, but about a year or two ago I designed this little constant-current buck converter as a means of regulating battery current to large LEDs (my friend builds ridiculously overpowered flashlights that melt stuff).
[img]http://i.imgur.com/h7zt7.png[/img]
U[sub]1[/sub] needs to be a comparator which can do rail-to-rail input (or at least very near GND)
R[sub]hysteresis[/sub] (and R[sub]1[/sub]) need to chosen carefully, as they influence the frequency of oscillation. If R[sub]hysteresis[/sub] is too high, it will fail to oscillate (or oscillate too quickly) and Q[sub]1[/sub] will probably burn up (or you'll just lose efficiency). If it's too low, it will oscillate slowly and you will get a lot of ripple in your output.
Now I'm partially bringing this up because it illustrates a question, but I'm also bringing it up because I think it might be of interest to you guys. It's, IMHO, [i]stupidly simple[/i], but if you google anything along the lines of a 'switching constant-current supply' or even just 'constant-current', all you get are these ridiculously over-elaborate designs or linear designs which are unsuitable where you need efficiency. It seems like this approach has been entirely overlooked even though it's both simple and (probably) efficient.
I didn't build it because there were tight space requirements within the enclosure and I'm still using big, fat DIP parts and perf board. It's self-oscillating, but the frequency of oscillation is uncontrollable. It depends on the load that is attached to it, so I was concerned about unintentional RF emissions.
Which brings me to my main point. How concerned do you have to be about unintentional RF radiation? I don't mean like accidentally broadcasting in full AM modulation or anything wacky like that, I just mean just how easy is it to cause interference to local RF transmitters/receivers.
[QUOTE=ROBO_DONUT;36326677]So, this is going way back, but about a year or two ago I designed this little constant-current buck converter as a means of regulating battery current to large LEDs (my friend builds ridiculously overpowered flashlights that melt stuff).
[img]http://i.imgur.com/h7zt7.png[/img]
U[sub]1[/sub] needs to be a comparator which can do rail-to-rail input (or at least very near GND)
R[sub]hysteresis[/sub] (and R[sub]1[/sub]) need to chosen carefully, as they influence the frequency of oscillation. If R[sub]hysteresis[/sub] is too low, it will fail to oscillate (or oscillate too quickly) and Q[sub]1[/sub] will probably burn up (or you'll just lose efficiency). If it's too high, it will oscillate slowly and you will get a lot of ripple in your output.
Now I'm partially bringing this up because it illustrates a question, but I'm also bringing it up because I think it might be of interest to you guys. It's, IMHO, [i]stupidly simple[/i], but if you google anything along the lines of a 'switching constant-current supply' or even just 'constant-current', all you get are these ridiculously over-elaborate designs or linear designs which are unsuitable where you need efficiency. It seems like this approach has been entirely overlooked even though it's both simple and (probably) efficient.
I didn't build it because there were tight space requirements within the enclosure and I'm still using big, fat DIP parts and perf board. It's self-oscillating, but the frequency of oscillation is uncontrollable. It depends on the load that is attached to it, so I was concerned about unintentional RF emissions.
Which brings me to my main point. How concerned do you have to be about unintentional RF radiation? I don't mean like accidentally broadcasting in full AM modulation or anything wacky like that, I just mean just how easy is it to cause interference to RF transmitters/receivers.[/QUOTE]
I think the mosfet wont turn off or on, just stay charged at a certain rate, meaning, this is linear.
[QUOTE=SubbyV-2;36328043]I think the mosfet wont turn off or on, just stay charged at a certain rate, meaning, this is linear.[/QUOTE]
See the positive feedback (hysteresis) on the comparator?
That prevents it from reaching equilibrium.
It depends on what power you're operating it at, but in general it should not be a problem.
I built a similar supply myself, although it did not work too well, I tried adding hysteresis and it had no effect on the oscillation frequency.
So I have this VFD I pulled from a microwave that I wanna use for a power supply at some point in the not too distant future. Problem is I know fuck all about VFD's apart from the fact that they need a somewhat high voltage or some stuff like that.
I took a picture of mine but I can not for the life of me find a datasheet for it, help me someone!
(thumbnails, right click and open in new tab do display properly)
[t]https://dl.dropbox.com/u/59112523/EEP%20thread/2012-06-16%2008.24.44.jpg[/t]
[t]https://dl.dropbox.com/u/59112523/EEP%20thread/2012-06-16%2008.24.00.jpg[/t]
Also some advice on building a switching supply for it would be much appreciated.
That weather station equipment is a nightmare to reverse engineer.
[IMG]http://i11.photobucket.com/albums/a166/ballsandy/stuffs.jpg[/IMG]
Okay, so the wind direction essentially works by increasing the resistance. The wind speed however runs by something really weird which does produce a pulse but it's not momentary at all.
[QUOTE=MIPS;36351143]Okay, so the wind direction essentially works by increasing the resistance. The wind speed however runs by something really weird which does produce a pulse but it's not momentary at all.[/QUOTE]
What kind of pulse, do you have an oscilloscope.
My guess would be it outputs a pulse for every revolution of the wind speed sensor, or part of a revolution.
[QUOTE=chipset;36350693]So I have this VFD I pulled from a microwave that I wanna use for a power supply at some point in the not too distant future. Problem is I know fuck all about VFD's apart from the fact that they need a somewhat high voltage or some stuff like that.
I took a picture of mine but I can not for the life of me find a datasheet for it, help me someone!
Also some advice on building a switching supply for it would be much appreciated.[/QUOTE]
I found the datasheet, or at least the product range overview, the proper part number is FIP4Q8A.
The package type is A-6, 2.4V AC filament (81mA).
[url=www.excesssolutions.com/mas_assets/acrobat/ES1672.pdf]datasheet[/url] (page 12 & 13)
If I'm reading this correctly is runs on 27V, so you can either use a linear supply or switchmode.
So I got bored and decided to measure the resistance of a meter of galvanized 0.65mm steel wire.
[t]https://dl.dropbox.com/u/59112523/EEP%20thread/2012-06-16%2010.55.56.jpg[/t]
that's a 2mV drop across the wire which is in series with a 1k resistor and is running on 11.5 volts.
[t]https://dl.dropbox.com/u/59112523/EEP%20thread/2012-06-16%2010.56.29.jpg[/t]
My sexy scope add-on multimeter shows 11.63mA through the entire thing, doing the math (0.002/0.01163=0.172) gives me a resistance of 172milliohms for a meter.
Here's what I made of that:
[t]https://dl.dropbox.com/u/59112523/EEP%20thread/2012-06-16%2011.57.08.jpg[/t]
A 1 ohm hand wound power resistor. Why? Why not!
I suspect either some non-linearity going on or measurment innacuracy in the 1 meter test because the math told me I'd need approx 6 meters of wire for 1 ohm (since 1 meter was 172 milliohms) but it turned out I only needed about half that. In retrospect I should have used a smaller value series resistor in the first test since a reading of 2mV on an el-cheapo meter is unreliable at best.
Still, I tuned it to the best my meters could do but it's probably only within %10 or something. Still I don't think I'll actually use it for anything but it was fun making.
I tested the power capability of it by putting 3 odd volts through it, since the amps range on my handheld meter is busted (keeps burning fuses for no reason) and my scope add-on meter doesn't go over 2 amps I couldn't measure the current but I did toss in my handheld measuring the voltage for good measure.
[t]https://dl.dropbox.com/u/59112523/EEP%20thread/2012-06-16%2012.02.30.jpg[/t]
It handled 6 watts pretty nicely, it got a bit too warm to hold after a couple of minutes but then it's wrapped in PVC tape so heat dissipation isn't gonna be stellar.
I did some further testing and it seems pretty spot-on, I wish I had a precision LCR meter or something but I'm quite pleased either way.
[editline]16th June 2012[/editline]
Btw in case anyone is wondering, the rod I wrapped the wire around is a busted CCFL originally made for ricing up computers. It lasted all of 2 days before the transformer in the inverter popped.
[QUOTE=chipset;36350693]So I have this VFD I pulled from a microwave that I wanna use for a power supply at some point in the not too distant future. Problem is I know fuck all about VFD's apart from the fact that they need a somewhat high voltage or some stuff like that.
I took a picture of mine but I can not for the life of me find a datasheet for it, help me someone!
(thumbnails, right click and open in new tab do display properly)
[t]https://dl.dropbox.com/u/59112523/EEP%20thread/2012-06-16%2008.24.44.jpg[/t]
[t]https://dl.dropbox.com/u/59112523/EEP%20thread/2012-06-16%2008.24.00.jpg[/t]
Also some advice on building a switching supply for it would be much appreciated.[/QUOTE]
[img]http://i.imgur.com/hWUrG.png[/img]
There we go, gotta love how you can see the traces on the back of the VFD.
Now to do some experimenting to figure out the anode voltage.
[QUOTE=Chryseus;36351926]What kind of pulse, do you have an oscilloscope.
My guess would be it outputs a pulse for every revolution of the wind speed sensor, or part of a revolution.
[/quote]
It's all in the notes. It also gives the pulse perhalf revolution.
[b][u]MY VFD, IT LIVES![/u][/b]
[img]https://dl.dropbox.com/u/59112523/EEP%20thread/2012-06-17%2000.39.51.jpg[/img]
My phone camera doesn't have manual white balance so the color is a bit off, it's a tad bluer than that in real life.
Big thanks to both Chryseus and Ddrl for helping me with this.
Make an incredibly impracticable vacuum tube based "portable" multimeter :p
[QUOTE=Tezzanator92;36360865]Make an incredibly impracticable vacuum tube based "portable" multimeter :p[/QUOTE]
It's probably gonna be a panel meter for a power supply.
[QUOTE=Chryseus;34496818]
[b]Video Lectures[/b]
[url=http://www.youtube.com/user/nptelhrd#grid/user/7987F30C41A9ADCB]Basic Electronics, Prof T.S.Natarajan - NPTEL[/url] [img]http://www.facepunch.com/fp/ratings/winner.png[/img]
Very well made lecture series with a lot of useful information, highly recommended.
[/QUOTE]
Someone should start downloading these videos and save them locally, the videos are not intended to be viewed by anyone that isn't from India. In other words they are going to go down soon.
[QUOTE=OnDemand;36367490]Someone should start downloading these videos and save them locally, the videos are not intended to be viewed by anyone that isn't from India. In other words they are going to go down soon.[/QUOTE]
... They've been there for ages and are intended for everyone just like the MIT lectures, why do you think they're in English??
[quote=Official Website]
NPTEL provides E-learning through online Web and Video courses in Engineering, Science and humanities streams. The mission of NPTEL is to enhance the quality of Engineering education in the country by providing [b]free online courseware[/b].[/quote]
It appears that NXP is producing an ARM microcontroller in a DIP package: [url]http://www.nxp.com/products/microcontrollers/cortex_m0/lpc1100_x_l/LPC1114FN28.html[/url]
[editline]18th June 2012[/editline]
On a related note, does anyone know where I can buy a STM32 discovery board without paying 20 € for shipping?
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