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Ask Slashdot: Projects For a Heap of Tech Junk? 210

yenrabbit writes "A friend has just told me he has 80 CRT TVs, a stack of DVD players and hundreds of VCR machines, all broken and all mine free of charge. I can already think of a few awesome components I can extract (flyback transformers for high voltage contraptions and so on) and have a few ideas, such as DVD lasers, that I can build. But what else can be made from such a treasure-trove of components, and how would one go about processing such a large volume of stuff with the least amount of effort? Also, I don't have access to online shopping so I'd also like a pain free way of salvaging many simpler parts such as resistors as well." Another reader sent in a similar question: "The other day I went down to my University's property disposition center for the first time. In addition to mundane things like chairs and desks, it also had a wealth of technological devices, from old PCs and monitors to obscure medical and chemistry equipment. Honestly, I was a bit overwhelmed. I just don't know what I'd do with a old gene sequencing machine or a broken oscilloscope. Any ideas for fun projects? Or better yet, suggestions on how I can figure out which machines (or their components) are worth playing with?"
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Ask Slashdot: Projects For a Heap of Tech Junk?

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  • Recycle it (Score:5, Informative)

    by Anonymous Coward on Friday March 01, 2013 @02:49PM (#43047631)

    Recycle it

    • Recycle it

      Yes, and do it before the cost to recycle it goes up.

    • Yes, thats about all. But really your friend is not your friend, he dosent want to pay $500 or more to get rid of all that stuff. I think the dump charges 5$ per crt for disposal. The thrift shops like value village dont even sell that stuff anymore, they fill big bins with crt tv's and monitors and vcr's they then have to pay to get rid of. They would probably be happy if you came in and hauled away a ton of their garbage too.
  • by Anonymous Coward on Friday March 01, 2013 @02:52PM (#43047671)

    Are you sure it isn't going to cost you a fortune later to get rid of the stuff you don't salvage?

    • Why do you think his "friend" is giving it away.

      OTOH..... gene sequencing machine.....ZOMBIE ARMY!!!!

      • It's probably an old one with impossible to get consumeables.

        Just wait a a couple of years. They'll be giving them away in cereal boxes.

    • Responsibly getting rid of the stuff, yes, it can cost money.

    • Re: (Score:2, Funny)

      by Anonymous Coward

      Disposing of old electronic junk is easy and profitable:

      1. Dig a hole.
      2. Put your electronic junk in it.
      3. Set fire to it.
      4. Collect all the gold and lead that dripped into the bottom of the hole.
      5. Profit!
      6. ???
      7. Die of cancer.

      That doesn't seem right.

  • by damn_registrars ( 1103043 ) <> on Friday March 01, 2013 @02:54PM (#43047689) Homepage Journal
    ... they are not nearly as straightforward to use as you might have imagined, even if you thought it would be difficult to use. If you don't have access to a way to purify your DNA for it, forget about it. Even if you could purify your DNA well, you would still need the supplies (primers, buffers, molecular-grade H2O, etc) to run the reactions and then the software to analyze the results. And then once you get one reaction to work you have to set up and run many many more to sequence even one important gene to a meaningful extent. That said, don't even dream of sequencing your entire genome at home with an older sequencer (or any other that you could afford on the kind of salary that a slashdot reader is paid).

    If you want some of your own DNA sequenced, send it off and then throw a big crazy party with the time, money, and space you saved by not attempting to do it yourself.
    • by geekoid ( 135745 )

      " If you don't have access to a way to purify your DNA for it, forget about it"
      you mean like ordering it online?

      " by not attempting to do it yourself."
      Booooooo. I would rather try learn and fail.

      • " by not attempting to do it yourself."
        Booooooo. I would rather try learn and fail.

        Well said; also notable, if you don't try, you will always fail.

        Dr. Seuss had a similar feeling, and it's only appropriate that I quote him on today, the day before his 109th birthday:

        “It is better to know how to learn than to know.”

      • by damn_registrars ( 1103043 ) <> on Friday March 01, 2013 @04:03PM (#43048521) Homepage Journal

        If you don't have access to a way to purify your DNA for it, forget about it

        you mean like ordering it online?

        No, not like ordering online. How do you expect to order your own DNA online if you want to sequence one of your own genes? And if you're going to send some of your cells to someone to purify your DNA, you might as well pay them to sequence it for you as they will have access to better instrumentation that will do it faster, cheaper, and more accurately.

        by not attempting to do it yourself

        Booooooo. I would rather try learn and fail.

        The problem is there isn't a whole lot to learn from doing this. Methods and instruments have changed dramatically. What you would learn from an old sequencer would not be useful for a new one because the methods and results are so dramatically different.

        To put it into a computer analogy, it would be similar to trying to learn computer animation by purchasing an old SGI Octane (after all, they used SGIs for Jurassic Park!) and spending a ton of money on old IRIX software, only to then realize that nobody uses it any more and you would have been better off financially and time-wise to buy a powerful PC and learn Blender.

        Hence if your goal is to learn the old method just to learn the old method, then go for it. Your results will likely be garbage and your chance of getting anything useful out of it are very slim (after all, someone did get rid of the old sequencer). If, on the other hand, you want to learn how it is done today, and get meaningful results, stay away from it and talk to someone with a sequencer from this decade.

    • Why not just try to sequence enough genes, to have it multiplied with a DIY PCM machine, and create the super deadly flu, which according to /. was capable of killing 50% of humanity?

      • Why not just try to sequence enough geness, to have it multiplied with a DIY PCM machine, and create the super deadly flu,

        For one, the flu has already been sequenced, so doing it again wouldn't be useful.

        Second, the flu genome is RNA, and around 14,000 bases long [] which is beyond what many PCR thermocyclers can do reliably, even with the best enzymes available. In other words, you would need better molecular biology techniques to get it to work well. Even more so, older DNA sequencers topped out at reading ~800 bases so you'd have to do a ton of sequencing in order to make sure you got your flu genome right after making yo

    • I imagine something like a wall length Kodak photo developing machine seen back in the 80s (local pharmacy like Eckerds, Walgreens, CVC... etc). So you find one of those used, eh? Ya, I agree. Send the film to be developed elsewhere. The chemicals, process flow, time,, so not worth it.

  • Components (Score:5, Interesting)

    by webmistressrachel ( 903577 ) on Friday March 01, 2013 @02:54PM (#43047693) Journal

    You quite rightly said that it'll be full of:

    Coils, ferrite magnets, capacitors, resistors, various discrete transistors and IC's, wires, motors, transducers (build a whacky digital backup medium using VHS tapes!), chassis pieces to build new projects on, raw materials (steel, plastic).

    If you can't think of anything, don't take it on. Recycling at the component level is VERY labour-intensive - one idea (and I don't want to give too many for free because this is my business) is to train volunteers for accredited qualifications in electronic repair and servicing (City and Guilds do a good course at different levels with almost that exact name). While they're learning, they can be labouring :-)

    • Brand-new electronic componets are unbelievably cheap. A reel of 5000 resistors is less than $7 these days ( Most surface mount components are not worth desoldering.

      You can buy all the red laser pointers you want for about $1 each if you know where to look.

      For high voltage experiments, you are (probably) better off with Neon Sign Transformers than with CRT fly back transformers. Modern fly back transformers tend to be very picky

      • by adolf ( 21054 )

        I've got a pile of old Laserdisc players here. Most kind-of work, but not really good enough for resale in the limited market that they've got, and none can be profitably tuned up to work well (at least, not with any profit for -me-). I keep prying them open hoping to find a HeNe gas tube laser, but haven't found one yet. They generally get trashed, whole.

        Small motors and stuff are fun, but they're also cheap as surplus items. They hardly seem worth the effort to scavenge when there's catalogs of them a

  • by ackthpt ( 218170 ) on Friday March 01, 2013 @02:57PM (#43047735) Homepage Journal

    And call yourself a Ham.


  • Also, I don't have access to online shopping so I'd also like a pain free way of salvaging many simpler parts such as resistors as well

    Save yourself the time and effort and get access to online shopping. Frankly, even if you have to wait a month or two, or place a bulk order, it'd be worth it. Standard rolls of resistors and capacitors are cheap.

    Not only that, but in modern technology most stuff is going to be surface mounted and useless to you. You'll probably find through-hole components in the VCRs, but it takes time and effort to desolder stuff, and you're left with tiny leads... all for a part that in bulk probably costs 2 cents. You

    • by pcjunky ( 517872 )

      On things like TVs and monitors I go for mostly the power components. Large wattage resistors, High voltage caps. Power transistors. Large diodes.

      These can be expensive to buy. You can get enough from 10 TV to have a nice stock. Use a Paint striping heat gun to remove the parts from the PCB.

      Don't bother with ICs except for standard ones like OP-AMPS, voltage regulators and such. These are mostly ASICs and of little use for anything but reparing now worthless TVs.

      Oh yea and one of the most useful parts, scre

  • by Hatta ( 162192 ) on Friday March 01, 2013 @03:02PM (#43047809) Journal

    EGA monitors are pretty rare these days. If you find some, offer them to the folks at the Vintage Computer Forums, they'll be appreciated.

    VCF would be a great place to find good homes for a lot of these items actually. Things like EMS cards for XT machines, or anything EISA.

  • and a tall building.
  • Old useless equipment + sledgehammer + $3 to take a few swings = money for charity

    • If it can't be fixed or reused then this is a great idea in so many ways. People need a way to dispose of pent up frustrations. Charge more like $/difficulty it is to completely destroy; and then sift through the pieces for precious materials, gold and copper and other metals.

      Anything that can be recycled should be, ie plastic, glass, metal etc...

      You'd just have to be willing to clean crap up. Make sure everyone wears safety goggles and they must sign a waiver so you're not held responsible for damages t

    • and a lawsuit for all the toxins which will get spewed into the air:

        - leaded glass in the CRTs (not to mention the voltage danger)
        - lead in the solder
        - cadmium in the PCBs


      Please recycle it responsibly.

  • CRT's have negative worth. We have a lot of CRT monitors sitting around gathering dust. I try to get people to just get rid of them the most benign way we can. They're worse than worthless. If you were standing on the street and someone handed you a CRT monitor, your net worth would drop.
    • That's a shame, because CRT monitors are still superior to LCD monitors. CRT monitors can handle various resolutions without having to scale, and the more expensive ones offer resolutions higher than HD. In several ways, LCD was a step back.

  • by Animats ( 122034 ) on Friday March 01, 2013 @03:19PM (#43048033) Homepage

    If you go to Weird Stuff Warehouse [] in Silicon Valley, you can get enough cheap previous-generation stuff to build a data center.

    • 1U rackmount servers, $50. Working, just obsolete by a few years.
    • Rack-mount networking gear. Working, just about 1/4 the density of current gear, and 100Mb/s, not gigabit Ethernet.
    • Rockwell 12-channel GPS module, $8.95. Nothing wrong with it, it's just 71mm across, which is huge by mobile standards. Good time standard.

    That's all working stuff, not junk. It's kind of depressing. Most of the gear there was valuable only a few years ago.

    There's a service in Oakland CA [] which takes discarded desktop systems. They check them out, try some board swaps to get them to work, clean them up, build them up to a minimally usable standard, wipe the hard drives, install Ubuntu Linux, and send them out to schools that need computers. That's about as good as recycling seems to get.

    • For example, I used to work for a steel fabrication company, and they had a "web press machine" out on the shop floor. Basically, it was just a big contraption with air compressors powering a punch on a moving arm, over a conveyor belt. Steel beams would roll up to it, and the machine would punch holes in the ends of them where the connector bolts would go when the beams were installed.

      The whole system ran an MS-DOS based program on a desktop PC installed in the metal cabinet that served as the "control pan

  • If you have, or come across, any laserdisc players, may I strongly suggest Ebay? They aren't made anymore, I've never been able to find anyone who can still repair them, yet I still actively collect anime laserdiscs (, and am not alone. I have 4-5 players, and if I can't find anyone who can do repairs, I wouldn't mind obtaining 4-5 more (once I move to a larger house, that is).

  • I must admit I am somewhat of a techno junk hoarder. However I found so many good things dumpster diving over the year. In addition to PC boards with resistors and caps, I also keep a look out on gear trains, and mechanical parts - laser printers are fun to digest. And of course stepper motors.. Always get stepper motors.. I made an XY table for my CO2 laser using nothing but printer parts. I have parts and circuit boards of devices in my "grave yard" that I look at now, and think - once upon a time this w
  • What a piece of junk!
  • Take it all, stack it six feet high in your house, and get yourself on an episode of Hoarders. Don't forget to find a friend or loved one willing to gasp at the sight of your hoard, shake their heads, and emotionally appeal to you to get all that junk out of your house.

  • If there is a place you can donate to a less-fortunate destination (local or overseas school, library, etc) then make this your priority.

    Else, if you can sell it in bulk on Kijiji/Craigslist for cheap (think $1 per monitor), then sell it, and donate the money to a good cause. They mightn't benefit from monitors and VCRs, but they can certainly use the money. I suggest in bulk, because you don't want to be supply-chain-managing a bunch of crap, do you?

    Else, if you can recycle it, do so. Hoarding a bunch of w

  • by bugs2squash ( 1132591 ) on Friday March 01, 2013 @03:40PM (#43048259)

    Some things you can't do with LCDs; tinker with the electronics until you have an unscanned beam of electrons from the back of the monitor tube making a bright spot on the screen and use a magnet to move it around. Make it safe for kids to touch the display and work the magnet. Set up an after-school event to talk to them about relativity, charge, atomic structure, bremsstrahlung, X-rays, the LHC etc.

    I used to mess up TV pictures with a magnet when I was a kid, it was fun to distort the actors on screen, but a lot of kids today may not get that experience. It's not a big thing, but I believe the experiences all add up.

  • by bobstreo ( 1320787 ) on Friday March 01, 2013 @03:49PM (#43048393)

    Gold is at 1,573.00 an ounce today.

    Here's a link to check out cpu prices based on gold content: []

    • You beat me to the punch. I would contact a gold recovery company. Send all that stuff in and get cold hard cash to buy new useful equipment.
  • by ArcadeMan ( 2766669 ) on Friday March 01, 2013 @03:50PM (#43048395)

    Scanners and printers are a good source of hard polished rods and bushings, belts and stepper motors with pulleys. You can build 3D printers and small desktop CNC mills with these parts. Old business-grade hardware usually has better parts too such as thicker rods and stronger motors.

  • And putting it on YouTube.

  • Take it all there and sell it.

  • Do you have a boat?

  • While you will find makers and hardware hackers on slashdot your mostly going to find kids who don't see the value in any tech they can't get a faster framerate than their friends playing the latest games on.

    You should be asking this on Hackaday's forum or better yet on your local hackerspace's IRC channel.

  • Something like the stegosaurus from the movie "The Squeeze".

  • by Colourspace ( 563895 ) on Friday March 01, 2013 @05:51PM (#43049553)
    If you have to ask on /., you really shouldn't be here in the first place.
  • And in case you did not get it: DO NOT COLLECT JUNK!
  • From that lot of junk you can probably only recover the metals: gold, aluminium and steel.
  • Save up enough CRTs for a decent capacitor bank. You're well on your way to being a supervillian.
  • Every time I see a post like this, I'm reminded that I have been down this road myself, and seen my family members suffer for it.

    If this is tempting, be honest with yourself, and look at your track record. I'll bet that you have alot of parts lying around for projects that are still "in progress". You have a reason that they are still "in progress", but realistically, you are never going to complete it. They are all waiting on something, and that thing they are waiting on is not actually in progress.

    Now you

  • PC boards etc sell for scrap on Ebay, for example.

    I'd tear down everything. You can scrap steel cases, copper separated into different grades (ask your scrap dealer how they want it), aluminum, lead batteries etc.

  • Personally I'd take about 8 or so Pentium 4's if they have it and store them in a closet just so I can set up a Gog Lan party [] whenever I want.
  • The collect the precious and heavy metals and sell them. Profit!

Garbage In -- Gospel Out.