Electrical Engineering V2

[DrLuke]

[url]http://www.ebay.de/itm/1000pcs-6x6x5mm-TACT-Switch-Push-Button-For-Arduino-AVR-ARM-PCB-/181134960939?pt=LH_DefaultDomain_0&hash=item2a2c7c292b[/url]

There you go

[Ddrl46]

[QUOTE=S31-Syntax;42551447]Huh... that picture format looks familiar...

Oh yeah!
[url]https://www.sparkfun.com/products/97[/url]

[editline]17th October 2013[/editline]

Also I got my VFD, but I cannot for the life of me get the thing to light up at all. I've followed the pinouts, loaded the example code, supplied the specified 5v, and it stays dark.[/QUOTE]

[del]Did you connect the fillament[/del] (didn't know you were using a module, oops) Could you maybe give a link to what tutorial / example code or whatever you are following?

[Chryseus]

[QUOTE=false prophet;42549480]The positive speaker or an exposed wire on any of the pots. Or really, any exposed wire for that matter.

[url]http://www.ti.com/lit/ds/symlink/lm386.pdf[/url]
Page six, the very first schematic.

Could this be an issue with a breadboard?[/QUOTE]

I can't see any obvious problem, check your breadboard, wiring and tell us what power supply you're using.

[S31-Syntax]

[url]http://www.noritake-elec.com/evalkit-sample.php[/url]

Its this guy right here.

Package came with the screen, a 6 pin cable with connectors, 6 headers, the data sheet, info packets, all that jazz.

Here's what I know:
I know its getting 5v at somewhere between 250 to 500mA
I have the serial baud rate set at 38400, this is what the example code shows plus this is what the datasheet shows is supported.
I know the pins are in the right spots [I]and[/I] I have the pins on the arduino board activated and set to either input or output, depending on what the data sheet shows.
This is the example code provided by the manufacturer, built for arduino boards.
The code also came with the complete code libraries for all the GU7000 VFDs from their company, which I have loaded and it compiles without error.

#include <GU7000_Interface.h>
#include <GU7000_Parallel.h>
#include <GU7000_Serial_Async.h>
#include <GU7000_Serial_SPI.h>
#include <GU7000_Serial_Sync.h>
#include <Noritake_VFD_GU7000.h>

// ****************************************************
// ****************************************************
// Uncomment one of the communication interfaces below.
//
//GU7000_Serial_Async interface(38400,3, 5, 7); // BAUD RATE,SIN,BUSY,RESET
//GU7000_Serial_Sync interface(3, 5, 6, 7); // SIN,BUSY,SCK,RESET
//GU7000_Serial_SPI interface(3, 5, 6, 7, 8); // SIN,BUSY,SCK,RESET,CS
//GU7000_Parallel interface('R', 8,9,10,11, 0,1,2,3,4,5,6,7); // Module Pin#3=RESET; BUSY,RESET,WR,RD,D0-D7
//GU7000_Parallel interface('B', 8,9,10,11, 0,1,2,3,4,5,6,7); // Module Pin#3=BUSY; BUSY,RESET,WR,RD,D0-D7
//GU7000_Parallel interface('N', 8,9,10,11, 0,1,2,3,4,5,6,7); // Module Pin#3=nothing; BUSY,RESET,WR,RD,D0-D7

//
// ****************************************************
// ****************************************************
Noritake_VFD_GU7000 vfd;

void setup() {
  _delay_ms(500);           // wait for device to power up
  vfd.begin(140, 16);       // 140x16 module
  // Enter the 4-digit model class number
  // E.g. 7040 for GU140X16G-7040A
  vfd.isModelClass(7000);
  //vfd.isGeneration('B');    // Uncomment this for B generation
  vfd.interface(interface); // select which interface to use
  vfd.GU7000_reset();       // reset module
  vfd.GU7000_init();        // initialize module
  
  
  // Print Noritake on screen.
  vfd.print("Noritake");
}

void loop() {
}

Uncommenting the first serial interface, I have all the pins in place, the board and the VFD are both getting power, I compile the code, send it to the board, board shows it got the code, display stays dark.

[Leestons]

As I said, I don't use Amazon for things like that because it's horribly overpriced, I use bits box instead, but I only use it when I buy a few things due to £1.75 shipping.

Does anyone know where I can find a bag of LEDs (100 or so) for really cheap?

[garychencool]

So yesterday we had day 2 and people suggested to start off with linux on day 1.

Ubuntu would not boot off the 3 bootable devices we had (including the CD, including the USBs we had, hell we even had to use mine.) Mine seemed to work fine :v:

There goes 10 minutes

[Chryseus]

[QUOTE=Leestons;42551857]As I said, I don't use Amazon for things like that because it's horribly overpriced, I use bits box instead, but I only use it when I buy a few things due to £1.75 shipping.

Does anyone know where I can find a bag of LEDs (100 or so) for really cheap?[/QUOTE]

Ebay.

[Metallics]

[QUOTE=Leestons;42551857]As I said, I don't use Amazon for things like that because it's horribly overpriced, I use bits box instead, but I only use it when I buy a few things due to £1.75 shipping.

Does anyone know where I can find a bag of LEDs (100 or so) for really cheap?[/QUOTE]

Definitely ebay, I got a bag of 1000 for about £8 the other week, just dont expect them all to work flawlessly.

[Quarternions]

Hey I am quite new in the world of electronics and have some experience with the arduino. For my first project I want to start of by building a power supply and I ordered a 230v transformer from bitsbox, this top one on this page : [URL]http://www.bitsbox.co.uk/transformers.html[/URL]

It clearly says single 230v winding but I got this :

[thumb]https://dl.dropboxusercontent.com/u/28926055/2013-10-17%2018.19.34.jpg[/thumb]

Is this normal (115v ?), maybe I am just a bit confused since I am all a bit new to this.

[S31-Syntax]

FFFFF[I]FFFF[/I]

Thumb that thing mang there are children here

[LoneWolf_Recon]

Before I offer advice, I should say, be *extremely* careful if you're new to working with line voltage. Hell I'd just say put it off for later project until you gain enough confidence to work with it, it can easily go bad, blah blah safety.

The xformer you have there is a dual primary/secondary transformers, quite useful for international power, you can easily switch between running off of US power (115-120VAC) or some international voltages (230-240VAC). Here's some different wiring diagrams to demonstrate how you can hook it up:

[IMG]https://fbcdn-sphotos-b-a.akamaihd.net/hphotos-ak-ash4/s403x403/5395_185848988240849_1823604078_n.png[/IMG]

I'd also recommend looking at the datasheet of that xformer for its VA rating (How much current it can deliver at a certain AC voltage).

I also recommend using copious amounts of electrical tape, heat shrink tubing on those connectors.

[DrLuke]

You shouldn't work AC out of your socket when you're still unexperienced, you can get hurt or die faster than you'd think.

[Chryseus]

[QUOTE=DrDevil;42553719]You shouldn't work AC out of your socket when you're still unexperienced, you can get hurt or die faster than you'd think.[/QUOTE]

nonsense, there is no time like the present to start learning, once you put it through a transformer you're perfectly safe, just make sure you insulate the connection with some electrical tape or heatshrink so you can't accidentally touch it.

[Quarternions]

[QUOTE=S31-Syntax;42553643]FFFFF[I]FFFF[/I]

Thumb that thing mang there are children here[/QUOTE]

Fuck, I uploaded it with my phone and then just went eating didn't see it was so big

[QUOTE=LoneWolf_Recon;42553653]Before I offer advice, I should say, be *extremely* careful if you're new to working with line voltage. Hell I'd just say put it off for later project until you gain enough confidence to work with it, it can easily go bad, blah blah safety.

The xformer you have there is a dual primary/secondary transformers, quite useful for international power, you can easily switch between running off of US power (115-120VAC) or some international voltages (230-240VAC). Here's some different wiring diagrams to demonstrate how you can hook it up:

-image-

I'd also recommend looking at the datasheet of that xformer for its VA rating (How much current it can deliver at a certain AC voltage).

I also recommend using copious amounts of electrical tape, heat shrink tubing on those connectors.[/QUOTE]

Thanks for the advice, I already bought some protective gloves and I got a shitton of electrical tape and shrink wrap because messing with 230v is scary :v:

[QUOTE=DrDevil;42553719]You shouldn't work AC out of your socket when you're still unexperienced, you can get hurt or die faster than you'd think.[/QUOTE]

Thanks for the advice bit I am pretty stubborn so probably going to do this anyway, already bought everything and you probably know how exiting it is to get new components :dance:

Also I based my design on this [URL]http://3.bp.blogspot.com/-roTnZeWqeKw/T3fss2A7GjI/AAAAAAAABA0/g-m_UUzpb3I/s1600/lm338+power+supply+circuit+digram.png[/URL] only replacing the 25v cap with a 16v one.
If I use the transformer in series (12v) so it becomes 24v and then use a 25v 470uf cap, would that work ? Bit concerned about voltage that goes up after a bridge/capacitor setup.

[Chryseus]

[QUOTE=quincy18;42553934]
Also I based my design on this [url]http://3.bp.blogspot.com/-roTnZeWqeKw/T3fss2A7GjI/AAAAAAAABA0/g-m_UUzpb3I/s1600/lm338+power+supply+circuit+digram.png[/url] only replacing the 25v cap with a 16v one.

Also if I use the transformer in series (12v) so it becomes 24v and then use a 25v 470uf cap, would that work ? Bit concerned about voltage that goes up after a bridge/capacitor setup.[/QUOTE]

The output voltage after rectifier is roughly:
(Vac * sqrt(2)) - 2
So assuming exactly 12Vac that becomes about 14.97V, and 24Vac becomes 31.94V so you'll want a bigger cap in both cases for extra room.

I'd also suggest adding a little output capacitance and a diode across the input and output of the regulator in the reverse direction of normal current flow.
Also the power dissipation is (Vin - Vout) * I, it should be mounted to a decent heatsink in any case.

[Quarternions]

[QUOTE=Chryseus;42555175]The output voltage after rectifier is roughly:
(Vac * sqrt(2)) - 2
So assuming exactly 12Vac that becomes about 14.97V, and 24Vac becomes 31.94V so you'll want a bigger cap in both cases for extra room.[/QUOTE]

Thanks, that's pretty handy, after sifting through my cap box I found out that I do not have a 25v 1000uf Cap (for the 12v parallel setup for the transformer). I only got some higher 16v(4700uf, 2200uf, 1000uf) caps and lower 25v caps starting from 470uf. I tried my hand at some ripple calculations but not quite sure if it will work out as planned so any thoughts on this ?

Edit :

I was doing this :

Maximum output of 5A (which I am not going to reach) mean

Vr = 5 * (1/50) / 0.47 = maximum ripple of 0.2127

[editline]17th October 2013[/editline]

[QUOTE=Chryseus;42555175]The output voltage after rectifier is roughly:
(Vac * sqrt(2)) - 2
So assuming exactly 12Vac that becomes about 14.97V, and 24Vac becomes 31.94V so you'll want a bigger cap in both cases for extra room.

I'd also suggest adding a little output capacitance and a diode across the input and output of the regulator in the reverse direction of normal current flow.
Also the power dissipation is (Vin - Vout) * I, it should be mounted to a decent heatsink in any case.[/QUOTE]

Yes, I read about the diode a while ago and will be adding that, I already managed to get myself a heatsink from some old scrap electronics. You also said this : "I'd also suggest adding a little output capacitance" This would mean another smaller cap at the output right ?

[Chryseus]

[QUOTE=quincy18;42555530]This would mean another smaller cap at the output right ?[/QUOTE]

Yes, it's not critical 10uF or so will do.
Also as a general rule 10,000uF per amp for very low ripple, you can reasonably reduces this to 2,200uF per amp and still get good performance, you don't want to go too mad as more capacitance increases peak current through the rectifier.
For even less ripple use a Pi configuration, capacitor, inductor and capacitor.

[Agent766]

I doubt I'll ever go near mains. I've always hated analog electronic. I'll stick to +/- 5/3.3V and not die kthx

[Chryseus]

[QUOTE=Agent766;42556801]I doubt I'll ever go near mains. I've always hated analog electronic. I'll stick to +/- 5/3.3V and not die kthx[/QUOTE]

It's really not that dangerous, I've shocked myself plenty of times from 250VAC to 350VDC and I'm still alive, granted knowing how to handle high voltage makes a big difference.
Also low voltage can kill you as well if you stab yourself with the conductor.

Thanks for boxes.

[Metallics]

[QUOTE=Chryseus;42556887]It's really not that dangerous, I've shocked myself plenty of times from 250VAC to 350VDC and I'm still alive, granted knowing how to handle high voltage makes a big difference.
Also low voltage can kill you as well if you stab yourself with the conductor.

Thanks for boxes.[/QUOTE]

Mains stings though

[Chryseus]

[QUOTE=metallics;42557304]Mains stings though[/QUOTE]

It certainly does, won't be making those mistakes again.

I'm not saying you should play around with mains like it's some toy, just treat it with caution and respect and you can do a lot of fun stuff.

[Tezzanator92]

Everyone gains a sudden respect for electricity shortly after their first "big" shock.

Got to love UK mains electricity, it has a sting the queen would be proud of.

[pentium]

Need to find a way to replace a D2732A EPROM with a diode matrix.
The only code on the EPROM is $1B in the second byte. Why the fuck didn't they just use eight diodes in the first place??

[Angus725]

[url]https://dl.dropboxusercontent.com/u/64514745/ECE212_2013-Lab%20%233.pdf[/url]

Mildly related to OP-AMP stuff discussed on previous page.

(Lab I need to do for tomorrow)

[bapapabapa]

[url=http://antg.cand.com.vn/vi-vn/phongsu/2011/11/78897.cand]bia heineken gia[/url] tri thuong hieu toan cau

[highlight](User was permabanned for this post ("Spambot" - MaxOfS2D))[/highlight]

[LoneWolf_Recon]

[QUOTE=pentium;42560644]Need to find a way to replace a D2732A EPROM with a diode matrix.
The only code on the EPROM is $1B in the second byte. Why the fuck didn't they just use eight diodes in the first place??[/QUOTE]

Perhaps this will help:

[URL="http://www.robotroom.com/AlphanumericDisplay.html"]Diode Array Rom[/URL]

[Quarternions]

[QUOTE=Chryseus;42555956]Yes, it's not critical 10uF or so will do.
Also as a general rule 10,000uF per amp for very low ripple, you can reasonably reduces this to 2,200uF per amp and still get good performance, you don't want to go too mad as more capacitance increases peak current through the rectifier.
For even less ripple use a Pi configuration, capacitor, inductor and capacitor.[/QUOTE]

Thanks, today I will be asking a friend's father if he still has some bigger capacitors and if I could use his scope to measure out the ripple. I will post some pictures today of the transformer hooked up to the circuit before putting it into the mains:v:

Soldered most of the project onto a board yesterday and hopefully can test it today :D

[TCWilliamson]

I got the power!
[img]http://i.imgur.com/bvC6u08.jpg[/img]

[Ddrl46]

[QUOTE=quincy18;42562052]Thanks, today I will be asking a friend's father if he still has some bigger capacitors and if I could use his scope to measure out the ripple. I will post some pictures today of the transformer hooked up to the circuit before putting it into the mains:v:

Soldered most of the project onto a board yesterday and hopefully can test it today :D[/QUOTE]

Make sure you put a small fuse in line with the primary of the transformer just in case.

[Chryseus]

[QUOTE=ddrl46;42562369]Make sure you put a small fuse in line with the primary of the transformer just in case.[/QUOTE]

Practically all transformers are thermally fused.