[QUOTE=Gulen;40128982]Yeah, I'm assuming it's about a switch to turn it on and such. Like having a push button to turn a motor on or off.[/QUOTE]
Well pretty much everything has a mechanical interface so we can use it as humans, so you shouldnt be short of stuff then!
pretty much any kind of flexsensor, gyroscope or accelerometer and the likes qualify as mechanical signals then, don't they?
[QUOTE=DrLuckyLuke;40129060]pretty much any kind of flexsensor, gyroscope or accelerometer and the likes qualify as mechanical signals then, don't they?[/QUOTE]
And pushbuttons
[QUOTE=LoneWolf_Recon;40051127]Everyone remembers those cheap USBASP programmers. Yeah, so if you by the Lcsoft v2.0 or Hobby King versions of them, you better be prepared to upgrade their firmware before you use it.
Finally got mine working today, it was a mixture of a bad ISP cable and old firmware. Thankfully my old serial port programmer still worked like a champ when I rinse-n-repeat soldered it to the ISP header on the USBASP stick.
[img_thumb]http://oi49.tinypic.com/2lcyd1j.jpg[/img_thumb]
Also, I found this useful for upgrading the firmware:
[URL="http://www.avrfreaks.net/index.php?name=PNphpBB2&file=viewtopic&p=1041690"]http://www.avrfreaks.net/index.php?name=PNphpBB2&file=viewtopic&p=1041690[/URL][/QUOTE]
I bought one very similar on ebay and it worked quite well.
I had read some nonsense about how the "chinese USBasps can only be used with chinese software" on RCGroups, but I was able to use mine just like a legitimate one.
[IMG]http://i54.photobucket.com/albums/g115/31337_tom/IMG_2879_re_small.jpg[/IMG]
Does yours have little stick figures on the silkscreen?
No, its just ye olde, run-of-the-mill, standard blue
[IMG]http://i1339.photobucket.com/albums/o711/joziasdelrios/usbasp_lcsoft_zps2c47ae2b.jpg[/IMG]
[IMG]http://i54.photobucket.com/albums/g115/31337_tom/IMG_4667_small_zpsedbff746.jpg[/IMG]
oh china
[img]http://i.imgur.com/aIaXnD3.jpg[/img]
Added some LED strip lighting to the back of my desk, pretty pleased with the outcome.
[QUOTE=SubbyV-2;40140681]Added some LED strip lighting to the back of my desk, pretty pleased with the outcome.[/QUOTE]
[del]Needs more test equipment.[/del]
I should say.
Needs test equipment..
Probably a silly question, and a silly place to ask, but can any of you help me understand what R5 is doing there?
[IMG]http://i.imgur.com/L0RwmHY.png[/IMG]
As far as I can understand, R3 reduces the amperage so that LD2 won't blow out. But won't R5 mean that T2 will get more amperage, as two ressistances in parallell (LD2 and R5) will mean a lower total ressistance?
[QUOTE=Warsheep;40164834]Probably a silly question, and a silly place to ask, but can any of you help me understand what R5 is doing there?
[IMG]http://i.imgur.com/L0RwmHY.png[/IMG]
As far as I can understand, R3 reduces the amperage so that LD2 won't blow out. But won't R5 mean that T2 will get more amperage, as two ressistances in parallell (LD2 and R5) will mean a lower total ressistance?[/QUOTE]
T2 will only get whatever amperage R3 allows due to how it's hooked up.
Some quick research shows that it's supposed to function as brightness control, perhaps.
Oh here we go again [url]http://www.lessloss.com/blackbody-p-200.html[/url].
[QUOTE=ddrl46;40166112]Oh here we go again [url]http://www.lessloss.com/blackbody-p-200.html[/url].[/QUOTE]
Hurrah for placebo sound enhancers.
[QUOTE=MIPS;40166011][IMG]http://i11.photobucket.com/albums/a166/ballsandy/Computer%20related/DPP_0034-1.jpg[/IMG]
[/QUOTE]
I have that exact set.
It's all crappy steel and I don't expect any of them to last particularly long, but finding all those security bits is a pain in the ass.
[QUOTE=ddrl46;40166112]Oh here we go again [url]http://www.lessloss.com/blackbody-p-200.html[/url].[/QUOTE]
This is possibly even dumber than the high-quality gold-plated SATA cables I've seen floating around.
[QUOTE=Zero-Point;40165819]T2 will only get whatever amperage R3 allows due to how it's hooked up.
Some quick research shows that it's supposed to function as brightness control, perhaps.[/QUOTE]
What happens when you hook things up in parallel? Shared current. I like to think of everything as a resistor...
LED and Resistor in series? No problem! Just treat it as a potential divider!
[QUOTE=Chrisz;40173053]What happens when you hook things up in parallel? Shared current. I like to think of everything as a resistor...
LED and Resistor in series? No problem! Just treat it as a potential divider![/QUOTE]
That'd be great if diodes obeyed ohms law like a resistor... but they don't...
It'd be beautiful if I could model a 3 phase induction motor as a pure resistance, or if I could create a high speed circuit board with exactly 0 capactiance between tracks, but that will never happen.
[QUOTE=metallics;40176329]That'd be great if diodes obeyed ohms law like a resistor... but they don't...
It'd be beautiful if I could model a 3 phase induction motor as a pure resistance, or if I could create a high speed circuit board with exactly 0 capactiance between tracks, but that will never happen.[/QUOTE]
Hm, yeah but the circuit in question was ultra simple... No 3 phase induction motors here!
No need to get all dicky on me when im helping someone out?
Anyway here's WIWO yesterday morning (Factory closes at 12:30 zing)...
bodge wires on dodgy pcb routing from the draughtsmen... CAD software is meant to check schematic and PCB is consistent... but then again draughtsmen are a massive headache. A few years ago us engineers would sit with the designer while he routed it. Stupid things like trying to pass 10A through 32thou track and inductors miles away from the control chip.
[IMG]http://i.imgur.com/E9IdKem.png[/IMG]
I spent today reading about the digital potentiometers I purchased a few weeks ago and did a little research into how to control them. After about an hour of playing around with things, I got the hang of SPI and was using it to control a simple oscillator circuit.
[media]http://www.youtube.com/watch?v=Xqo8wNj8p74[/media]
It's only basic at the moment, but sets some very firm foundations for the synthesizer component of my keyboard. Once I grab another USB cable tomorrow, I should be able to get to work sending keystrokes via serial from the keyboard controller to the synth.
[QUOTE=HiddenMyst;40192897]I spent today reading about the digital potentiometers[/QUOTE]
They work by a tiny servo connected to a shaft of a pot :)
[QUOTE=Chrisz;40193240]They work by a tiny servo connected to a shaft of a pot :)[/QUOTE]
Not quite, they usually are a bunch of resistors inside a chip, and they truly act like a potentiometer.
[QUOTE=Chrisz;40182230]
No need to get all dicky on me when im helping someone out?[/QUOTE]
Your not helping someone out when your information is wrong, metallics clearly pointed out your error so you should instead be thanking him.
[QUOTE=Chrisz;40193240]They work by a tiny servo connected to a shaft of a pot :)[/QUOTE]
That's only true for large (older) amplifiers with a remote that can do the same as the buttons on the front panel.
My Technics one from early 90's work that way, but modern amplifiers have fully digital & non-mechanic solutions.
I've got some new test gear!
Cossor CME-110A Cable Tester
[url=http://i.imgur.com/NE8YfMQ.jpg][img]http://i.imgur.com/NE8YfMQh.jpg[/img][/url]
(Inside pictures here: [url]http://imgur.com/a/9DQcT[/url], it's beautiful)
Another Philips PM 3200 and Philips PM 2513
[url=http://i.imgur.com/WtxWTPo.jpg][img]http://i.imgur.com/WtxWTPoh.jpg[/img][/url]
Not shown: IBM Portable 5155
[QUOTE=DrLuckyLuke;40193252]Not quite, they usually are a bunch of resistors inside a chip, and they truly act like a potentiometer.[/QUOTE]
[IMG]http://i.imgur.com/9G9xo36.jpg[/IMG]
[QUOTE=alexaz;40120542]A thing popped up in my mind: When the dremel discs shatter, are they capable of fucking shit up everywhere? I have blown up a few of them while cutting with the pieces never to be fount, but they havent broken anything. I wonder if a shattered disc could fuck a monitor up or break a window from 2 meters away where cutting was done[/QUOTE]
I remember in house there a one patient who had tiny fragments of metals from workshops and their disks in his eyes which fucked his vision up whenever he went near the mri
[editline]8th April 2013[/editline]
[QUOTE=ddrl46;40166112]Oh here we go again [url]http://www.lessloss.com/blackbody-p-200.html[/url].[/QUOTE]
if it blocks the mains hum then it could be p useful for kidnappers or forgers
[t]http://i.imgur.com/d6PkeCk.png[/t]
Could someone have a quick glance at my regulator circuit? It looks fine to me, but it feels like something is wrong lol
[QUOTE=alexaz;40217860]Could someone have a quick glance at my regulator circuit? It looks fine to me, but it feels like something is wrong lol[/QUOTE]
I'll go through it as I see it and point out any obvious problems.
op-amp B senses the voltage drop across the current shunt R1 and amplifies it by 1 + R5 / R4 giving a feedback voltage of I * R1 * Av.
op-amp A controls Q2 adjusting the current to the load given by the above equation, the gate drive voltage must be able to swing close to the input voltage since ID is dependant on Vgs - Vt which in practice means op-amp A should have a supply voltage equal or greater than the input (there are other options).
op-amp D is a standard voltage regulator however as with op-amp A the gate drive must be at least close to the input voltage.
The circuit is also not quite stable and will be effected by noise in the power supply or reference voltages, possibly in worse case causing it to oscillate.
R3 and R2 are not needed due to the internal output circuit of the op-amps which prevents the transistors getting stuck on, if your directly driving a mosfet it's a good idea to add a small series resistor (< 100 ohm) to help isolate the op-amp from the gate capacitance which can cause instability.
Simulation of the circuit in LTSpice showed some issues so I thought fuck it and redesigned it to use one transistor, this does not include the current amplifier but you can add that yourself easy enough.
Feel free to ask questions.
[t]http://u.cubeupload.com/Chryseus/MZnXOw.png[/t]
[url=https://mega.co.nz/#!LxhTzQYS!PE9EwGASfWCoY4ywBnbsMhmfaoFrPb5zzE_5VU6_ljE]LTSpice file[/url]
Eh I forgot the capacitors, I suggest 10nF to 100nF between the output of each op-amp and the non-inverting feedback.
Wow! Thanks alot! I built your schematic on the breadboard with BC337-40 transistors ([url]http://www.onsemi.com/pub_link/Collateral/BC337-D.PDF[/url]). The problem is even that the both op amps outputs are high, yet the gate of the mosfet is at 0V. The voltage at transistor bases is 0.7V and the voltage drop across the (pull-up, i assume) resistor R2 is the entire VCC.
EDIT: Nevermind, seems like i have mixed up the inputs of the op amps
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