• Electronics and Embedded Programming V3
    1,545 replies, posted
  • Avatar of Chryseus
  • [QUOTE=DrLuke;35204200]And Nitrous Oxide which is the stuff that really stings[/QUOTE] What Also any power resistors, transformers, transistors, DIP chips. I.E anything you can get out of it.
  • Avatar of Tw34k
  • [QUOTE=demoguy08;35203730]Are there any juicy stuff to salvage from an old CRT tv? The electron gun itself is most likely damaged (might just be some capacitors though) and I've ripped out the speakers.[/QUOTE] Most of the parts I got from the last CRT I scavenged. They are always guaranteed to have a few good heat-sinks in them. [t]http://i924.photobucket.com/albums/ad84/tw34kpics/Electronics-Tech/389384_2682087941398_1532330395_2712039_1684429744_n.jpg[/t] Even though they are dirt cheap, for some reason I get excited when I score second hand 5+ watt resistors.
  • Avatar of demoguy08
  • Alright, might go a second round with it tomorrow. Retrieved a 2Mbit EPROM IC, have no idea how to read from it though.
  • Avatar of LoneWolf_Recon
  • [QUOTE=demoguy08;35206401]Alright, might go a second round with it tomorrow. Retrieved a 2Mbit EPROM IC, have no idea how to read from it though.[/QUOTE] What's the chip ID?
  • Avatar of demoguy08
  • M27C2001. Google gives this: [url]http://se.farnell.com/stmicroelectronics/m27c2001-10f1/ic-eprom-cmos-2mb-tube12/dp/1661758[/url]
  • Avatar of LoneWolf_Recon
  • [QUOTE=demoguy08;35208099]M27C2001. Google gives this: [url]http://se.farnell.com/stmicroelectronics/m27c2001-10f1/ic-eprom-cmos-2mb-tube12/dp/1661758[/url][/QUOTE] Okay its a parallel EPROM, meaning you sequentially plug in the address you want to read to the Address Pins and apply the voltage to the right pin combination as described on page 8 in the datasheet. You could use four 4 bit binary ripple counters(That cascade upon the next) to cycle through the entire address range of the chip and just have a microcontroller read the values on the 8 bit data bus.
  • Avatar of demoguy08
  • [QUOTE=LoneWolf_Recon;35208214]Okay its a parallel EPROM, meaning you sequentially plug in the address you want to read to the Address Pins and apply the voltage to the right pin combination as described on page 8 in the datasheet. You could use four 4 bit binary ripple counters(That cascade upon the next) to cycle through the entire address range of the chip and just have a microcontroller read the values on the 8 bit data bus.[/QUOTE] Hmm, that's a fair bit above my knowlegde of IC's (aka nearly nonexistant). With the risk of sounding like a newb, would the method you describe be possible with an Arduino? Say if I were to create a program that outputs the addresses on a digital pin and reads the incoming data on another.
  • [QUOTE=demoguy08;35208389]Hmm, that's a fair bit above my knowlegde of IC's (aka nearly nonexistant). With the risk of sounding like a newb, would the method you describe be possible with an Arduino? Say if I were to create a program that outputs the addresses on a digital pin and reads the incoming data on another.[/QUOTE] You have a few data lines, A0 to A16 (You don't have to use all data lines if you ground the rest), you send it a address by setting the appropriate pins (and make sure you pull the enable pin low) and then you get the data for the specific address on the Q0 to Q7 outputs.
  • Avatar of LoneWolf_Recon
  • [QUOTE=demoguy08;35208389]Hmm, that's a fair bit above my knowlegde of IC's (aka nearly nonexistant). With the risk of sounding like a newb, would the method you describe be possible with an Arduino? Say if I were to create a program that outputs the addresses on a digital pin and reads the incoming data on another.[/QUOTE] Sure! As long as you have the pins. To access the entire contents of the chip you need 16 pins allocated for addressing, 3 for control, & 8 for data(Which I believe is above the standard Arduino's capability unless you have like the ADK or Mega model). Assuming you are using the standard model with 14 pins, you still need 3 for the control pins & 8 for reading the output data. Leaving you 3 pins to address the chip. :/ Now you could use a 74HC595: [URL="http://www.youtube.com/watch?v=h84cDS7_9Pg"]http://www.youtube.com/watch?v=h84cDS7_9Pg[/URL] And that will free up some pins allowing you to probably address all the data.
  • Avatar of demoguy08
  • Alright, thanks for the advice. Looks like this is gonna turn into a little project of mine, figure it could be a nice way to learn more about ICs and electronics.
  • Avatar of Tw34k
  • If my parts from tayda aren't here soon I'm going to chew my fingers to the bone with anticipation. I need panel mount pots yesterday :suicide:
  • [QUOTE=Tw34k;35210982]If my parts from tayda aren't here soon I'm going to chew my fingers to the bone with anticipation. I need panel mount pots yesterday :suicide:[/QUOTE] On the topic of panel mount pots, I've always hated that the only stereo potentiometer that Radioshack sells is 100kohm. I'm sure stocking 100kohm made sense way back in the day when people were working with tube designs that had 1Mohm input impedances, but today the typical solid state amp has an input impedance of like 10k-100kohm. So, like, all of my designs have to be based around RS's quirky component stocking policies.
  • Avatar of Tw34k
  • I'm down to only about 5-10 radioshack visits a year. I hate that place now. So, I'm thinking about just building my own isolation transformer for my scope, would something like this be sufficient? My scope draws less than 300mA. [url]http://www.ebay.com/itm/ISOLATION-TRANSFORMER-Arcade-Video-Game-Dynamo-Cabinet-115V-105-115-125V-/350546058144?pt=LH_DefaultDomain_0&hash=item519e2c5ba0#ht_568wt_1032[/url] Recommendations are warmly welcomed.
  • Avatar of demoguy08
  • On the subject of shift registers - turns out I have a whole bunch of 74LS195AN/138 DIPs. Google reports them as "4-bit parallel-access shift registers". Will they do for what I'm trying to accomplish?
  • Avatar of DrLuke
  • Friendly advice: Learn to read datasheet. Most of them are very well written and explain everything very well. Those that aren't are a bit tough to go through, but you still get all the information you need.
  • Avatar of chipset
  • Disassembled a microwave today! Microwave in question [img_thumb]http://dl.dropbox.com/u/59112523/Microwave%20disassembly/007.JPG[/img_thumb] Panel off! [img_thumb]http://dl.dropbox.com/u/59112523/Microwave%20disassembly/006.JPG[/img_thumb] Mmm, the grand prize! [img_thumb]http://dl.dropbox.com/u/59112523/Microwave%20disassembly/003.JPG[/img_thumb] [img_thumb]http://dl.dropbox.com/u/59112523/Microwave%20disassembly/052.JPG[/img_thumb] [img_thumb]http://dl.dropbox.com/u/59112523/Microwave%20disassembly/053.JPG[/img_thumb] [img_thumb]http://dl.dropbox.com/u/59112523/Microwave%20disassembly/056.JPG[/img_thumb] Gonna make a spot welder, wish me luck!
  • Avatar of demoguy08
  • [QUOTE=DrLuke;35220678]Friendly advice: Learn to read datasheet. Most of them are very well written and explain everything very well. Those that aren't are a bit tough to go through, but you still get all the information you need.[/QUOTE] Alright, I'll give it a try.
  • Avatar of LoneWolf_Recon
  • [QUOTE=chipset;35221118]Disassembled a microwave today! [...] Gonna make a spot welder, wish me luck![/QUOTE] You should extract the Magnetron, you could sell it on eBay for some good money.
  • Avatar of SubbyV-2
  • [QUOTE=LoneWolf_Recon;35222541]You should extract the Magnetron, you could sell it on eBay for some good money.[/QUOTE] Why would anyone want a magnetron?
  • Avatar of DrLuke
  • [QUOTE=SubbyV-2;35228110]Why would anyone want a magnetron?[/QUOTE] DIY Radar obviously duh
  • [QUOTE=SubbyV-2;35228110]Why would anyone want a magnetron?[/QUOTE] To kill themselves of course.
  • Avatar of DrLuke
  • [QUOTE=ddrl46;35228912]To kill themselves of course.[/QUOTE] Atleast they'll be well done
  • Avatar of Tw34k
  • [QUOTE=SubbyV-2;35228110]Why would anyone want a magnetron?[/QUOTE] [IMG]http://3.bp.blogspot.com/_ESC4bygtp2M/SO1SDYTiCdI/AAAAAAAAGfI/Juy63Ili-kI/s400/Abbeville+Interview.jpg[/IMG] "We have ways of making you talk, Mr Bond."
  • Avatar of Overv
  • By request of DrLuke, my rendition of 2 girls 1 cup of soldering: [img]http://puu.sh/lLZb[/img]
  • Avatar of Zero-Point
  • [QUOTE=Overv;35234499]By request of DrLuke, my rendition of 2 girls 1 cup of soldering: [img]http://puu.sh/lLZb[/img][/QUOTE] :vomit:
  • What kind of iron/solder are you using? D: My soldering used to look like that when I was using an old, oversized Weller ~300W soldering gun, ~30 year old flux and lead-free plumbing solder.
  • Avatar of Overv
  • [QUOTE=ROBO_DONUT;35234795]What kind of iron/solder are you using? D: My soldering used to look like that when I was using an old, oversized Weller ~300W soldering gun, ~30 year old flux and lead-free plumbing solder.[/QUOTE] Yeah I have an old way too big soldering gun. I am using decent S-Pb60Sn40 solder, though. [img]http://puu.sh/lMiX[/img] I just ordered a [url=http://www.conrad.de/ce/de/product/588415/ANALOGE-LOeTSTATION-ZD-99-48-W/SHOP_AREA_17589&promotionareaSearchDetail=005]new one[/url] to solder this: [img]http://puu.sh/lMkU[/img] Wish me luck.
  • Yeah, if you plan on doing a lot of electronics in the future, I recommend investing in a regulated iron with a thinner tip, and buy a pack of copper scrubby pads from the dollar store. Some people like wet sponge, but I've always had better success with copper scrubbies. Make sure you keep the tip of the iron tinned so it doesn't oxidize. If it's oxidized, it won't transfer heat effectively, and you'll end up with cold solder joints. Also, you might already know this, but when you solder, you want to heat the two surfaces, not the solder. What you do is you feed the solder in from the opposite side of the iron. Touch it just briefly, if you need to, to get a dab of liquid solder to transfer heat, then quickly pull it away and keep it opposite the iron. When the parts/pads are hot enough to melt the solder on their own, then you can pull the iron and solder away. It shouldn't take more than a second, and you shouldn't use more solder than necessary. The joints should be shiny and concave, not dull and convex.
  • Avatar of Chryseus
  • Holy shit. Get a decent solder station like a Hakko, or anything with temperature control. Use new good quality brand name 60/40 solder (I can't see any flux residue on those joints, assuming you did it right) Heat the pad and component lead then feed solder on, don't just try paste it on with the iron. Lick the joint when done so you get a nice shine. Don't forget a desoldering pump for when you make mistake or want to desolder, also wick.
  • Avatar of LoneWolf_Recon
  • [QUOTE=ROBO_DONUT;35235305]Yeah, if you plan on doing a lot of electronics in the future, I recommend investing in a regulated iron with a thinner tip, and buy a pack of copper scrubby pads from the dollar store. Some people like wet sponge, but I've always had better success with copper scrubbies.[/QUOTE] I've also had luck with steel wool.