My Kingdom For A Capacitor

While working on a project recently, I required a capacitor of around 1000 μF and went rummaging through my collection of parts. No luck there. At that point I’d usually go through my collection of junk electronics and computer motherboards, but I had recently gone through and tossed the stuff that had been laying around for as long as I could remember. No matter, I thought. I’ll just head over to RadioShack and…

Now, I have been accused of many things over the years, but “deep” is certainly not one of them. Yet, at this moment I had what could only be described as an existential crisis. There is no RadioShack, not in my state at least. I don’t live in an area that’s blessed with a maker “scene”, so no independent shop or even a hackerspace within reasonable driving distance of me either. I could order it online of course, but everyone’s trying to sell them in bulk and shipping will take a few days at least. A few days? Who knows where my interests will be in a few days. How can I get anything done under these conditions?

Desperate times call for desperate measures, so I got in the car and took a ride to the only place I knew where I could by electronic components for cheap: Goodwill.

Second Hand Salvage

If you aren’t familiar with Goodwill, it’s a second hand store where all manner of goods are sold, usually for a pittance. While the stock at Goodwill tends to be largely clothes, each one of their locations I’ve ever been into has had an electronics section in a back corner somewhere that has piles of crusty old VCRs, tape decks, tube televisions, etc. Basically any antiquated piece of consumer electronics that the owner felt too bad to just throw in the garbage: you’ll find it here. Of course, Goodwill is not really unique in this regard. If you’ve got a local second hand or thrift store, it’s likely they have a similar area.

In a RadioShack-less world, I suggest you become well acquainted with these types of stores and the wares they tend to deal in. It might be time to start checking in every week or so if it’s not out of your way. Because if you aren’t lucky enough to live in a hotspot of makers or hackers, and are too proud to garbage pick, stores like this may as well be your RadioShack now.

During my trip, I had no problem finding what I was looking for. There were plenty of VCRs and radios lying around, none more than $5 each. If you’re looking for good sources of through-hole components, you’ll probably want to stick to the older and cheaper looking hardware. The higher end devices would be more likely to have switched over to SMD components or other miniaturization techniques which might make salvaging parts from them more annoying.

Tools of the Trade

If you’re going to be salvaging parts out of old electronics, you’ll need to master the art of desoldering. [Bil Herd] did a great write-up and video of the various tools and techniques a few years back, but at the absolute minimum you’ll need some desoldering wick. If you want to make things easier for yourself, get a solder sucker or even better a desoldering iron.

In my case, I was lucky. The VCR that I selected came apart easily, and had its power supply on a nicely removable module that I was able to yank right out of the case. Inside it looked a bit nasty, some kind of sticky yellow fuzz covered most of the internals of the machine; if I had to guess, I would say this came from a smoker’s home. But for a $3, we can’t be too picky.

Sticky, but serviceable.

Power supplies are always a wealth of electrolytic capacitors, and it only took a few seconds to identify a 1000 μF capacitor that didn’t appear to be bulged. Remember that the hardware you’re dealing with can be rather suspect, and a close visual inspection is in order for all parts you are considering putting into your project.

After getting it freed from the PCB, I was able to check it with my multimeter and see it was at about 900 μF, which puts it within the tolerances for this kind of capacitor. Electrolytic capacitors are notorious for failing with age, and care should be taken to make sure you aren’t going through all this trouble for nothing.

The Day is Saved, For Now

In the end, I was able to get the capacitor I was after (plus a load of other passives and components I pulled out of the VCR) in about an hour and for only a few dollars. Certainly a better deal than ordering a single capacitor online, but still something I’d have rather avoided. Now that there are no more local electronic component shops in my area, it may be time to bite the bullet and just load up on bulk passives from eBay before I actually need them. But having a contingency plan like this never hurts.

In this dystopian post-RadioShack wasteland, where are readers getting their components? Are you lucky enough to live in an area where parts can be locally sourced? Are you buying in bulk online and just hoping you can predict what parts you’ll need? Maybe you’ve gone full Mad Max and how just build everything out of what can be found in the trash?

Let us know in the comments, and be sure to drop us a line if you’ve got your own salvage success story.

148 thoughts on “My Kingdom For A Capacitor

    1. In my youth, I stopped by the TV repair shop (remember when TV’s were fixable?) and picked up a few chassis that were deemed uneconomical to repair and stripped them for parts. I still have some of those parts.

      Though I did get one of them working and hooked up to my ZX-80.

      Solution is to sort and store the parts well so you know where they are when you need them. I needed a non polarized 150uF cap a few days ago. Guess where it came from?

      1. I did that when I started with electronics (when there was no nearby shop and ordering on-line didn’t exist) but now I just have learned which parts are located where on a typical TV PCB, so I just keep the assembled PCB and know where I can find the part I need. Also a good source for resistors that can be used for load-testing. upto about 12V you can also solder on some leads and dump the resistor in a bucket of water for almost infinite wattage without noisy fans or messing with cooling fins.

          1. Once we did that on purpose: For load testing a 0-100V/2A PSU. We put two stainless steel plates (20*20cm) into a bucket of tap water. The load was changed by varying the distance between the plates. It turned out, that “stainless steel” does not stay so under this conditions. The contents of the bucket changed to a reddish brown soup.

      2. It might relieve you to know that not only are tube TVs still repaired in some parts of the world, but when they finally die completely, all components are desoldered and the coils of copper wire on the CRT tube unwound, and carefully rewound into speakers and electric motors. The market is not far from my home, I see them doing this by hand from time to time.

        Some of the parts are then reassembled into karaoke systems and audio amplifiers. You can also buy the logos of major electronics brands, if you catch my meaning. Occasionally you see something hilarious like a Toyota speaker system or Microsoft Certified pants.

        I really wish I had a photo of the Microsoft Certified pants for you. So many possible jokes about security holes and patches. Well, we all have our regrets.

        On a related note Google tells me that Microsoft made cellphone-charging pants in 2014?

    2. I occasionally build some basic audio amplifiers from donor parts. However, the loss of the “Cheap” Radio Shack prototype boards will suck. Our Radio Shack just closed recently.

  1. I’ve been salvaging parts off of dead and unwanted electronics since I started getting into the hobby 30 years ago as a teenager (man, has it really been 30 years?!?). I’ve used those parts many times over the years to make repairs and build projects. I have both capacitors and resistors organized in drawers labeled according to the 10% series, so I have no trouble finding the right drawer when I need a part. Whether or not that drawer actually has the part I need is another issue entirely, though I did clean the local Radio Shack out of small parts when they went out of business, so I’m fairly well equipped these days.

    1. Our last Radio Shack closed without them bothering to inform me. I found it closed when I sent there to get a PL259. I’ve order a few on line but wont get them until next week. Sigh.

      At one point we have 5 in the area. Plus three private suppliers (all are long gone).

  2. Yes Radio shack is leaving our area also. Hadn’t thought of Good Will, great idea. Lucky to have Skycraft 45 minutes away as a backup.

    Edison once said “To invent, you need a good imagination and a pile of junk.” Or at least Good Will.

    1. You must live in the Orlando area.

      I was down at Disney earlier this week and wrapped up my trip with a jaunt across town to Skycraft on Tuesday morning. They relieved me of $150 in about 30 minutes. Second time I’ve been. You’re 45 minutes away? You. Lucky. Bastard.

      1. Yes Orlando, actually less than 30 minutes from Skycraft. Used to live in San Jose area, that was a dream come true for parts at least back then. Glad skycraft is not any closer else I would be popping over more often and getting relieved of $150 too often. If you come again, close to Skycraft is an awesome RC store with more RC airplanes etc hanging from ceiling than you have ever seen. Worth the visit just see see what they have.

  3. Reusing parts is fine in a pinch, but electrolytics are the worst possible parts to scavenge for.

    To be honest, I used to think salvaging was the best thing ever — now I recognize it for the waste of time it largely is. For 99% of passives and ICs, buying new is just a whole lot cheaper if you include the time spent. There’s just no real need when digikey and mouser will provide decent pricing and 2 day turn around times unless you need something in the next few hours.

    That being said, I’m totally willing to salvage linear motion parts, certain motors, lens assemblies, vacuum chambers, etc, simply because they’re difficult and expensive to buy new.

    1. I would totally agree except that two days of delay puts me out of the groove, and into another work week. There is almost no chance my inspiration will survive yet another work week.

      1. It can be a valuable investment to spend time rewiring the way your inspiration works. If you can wait a while, really cool options are available. For example…if you are inspired, instead of rummaging through piles of junk you can sit down and design a small PCB. Order the PCB from OSH Park and either order the parts or put them in a shopping cart to be batched with the next inspiration’s parts. You get to work on each inspiration and take them all the way through to a prototype in one shot. Later, the PCBs arrive and I find that is exciting enough to make the project inspiring enough to assemble and test.

        1. Thanks macegr. I have no doubt that you are correct. If only I could find an easy-to-use motivation reflow oven. In all seriousness, I see wisdom in changing the project steps to more closely match my inspiration half-life

          1. I too have trouble getting motivated sometimes and I do what macegr suggests. PCB design is a useful skill and you end up with much higher-quality hacks. You can also have a handful of different designs pipelined on the go at any given time, so you can work on any of them when the inspiration strikes. When you submit a PCB order, you also submit the order for any parts you’re missing. Couple of weeks later, it’s all there and you can

            I use a $20 hotplate to reflow SMD components. You don’t need fancy oven controllers or any such crap. Getting some low-temp bismuth solder paste will make it a bit easier too, as the board won’t get as hot before it reflows.

    2. What do you salvage vacuum chambers from???
      When really young, salvaging and sorting parts went a long way to get me familiar with them. Sorting resistors early helped me learn the color code.

  4. A good source for high voltage components is dead fluorescent electronic ballasts A couple in front of me:

    47 microfarad 250v and 50V electrolytic
    .0056,.0082 microfarad at 1250V metallized film
    .24 microfarad at 400V metallized film
    1 microfarad at 200V metallized film
    D13005 400V 4A switching transistors

      1. Polychlorinated biphenyls are rare in consumer electronics. They are liquids, and generally only used in high voltage (1000 volt and up) capacitors and transformers. The PCB capacitors would be fully sealed metal units, much larger in size than an electrolytic with similar energy storage.

      2. I think before 1980 there were nearly no electronic fluorescent ballasts. And the PCB containing cap was not mounted on an PCB :-) It had a screw stud for mounting and was the phase compensation cap for the magnetic ballast choke.
        Electrolytics are safe in that regard. But I would avoid salvaging them because of their limited lifetime.

  5. Unfortunately, this seems to be a self fulfilling death spiral. Our local electronics parts places have folded, all but one, and they are only still around as a tax write-off. Stock isn’t getting replaced, but it is _the_ place to go if you need that IC that hasn’t been made in 40+ years. There are a few of the 7400 series that the pinout is different when you move to 74{LS,C,ACT,etc}.

  6. I think there should be email distribution lists of the hackers in your local area that you could contact in situations like this. I’m sure there are 10s of people close to me that probably have stuff I don’t have. If the Neighborhood website is operating in your area you could probably just put out a call there.

      1. I think it would have to be push-based. Certainly I’m not going to go to CL or the Hackday forum every day and check to see if I can give away my stuff, but if there was an email list of only my local hacker neighbors and it showed up once or twice a day I’d be likely to look at it and see if I can help out.

        I get the Neighborhood website’s digest every evening and I usually glance at it to see if I can help or if there’s anything interesting in the classifieds. A couple of weeks ago some guy was looking to make 1 cut with a tile cutter. I dragged mine out, set it up and let him know. Magically a 6-pack of beer showed up on my doorstep the next day.

  7. My whole electronics lifestyle pretty much began with salvaging parts. The University where I live has auctions on a regular basis that are a gold mine of old computers and printers and such. But often boxes of amazing stuff when somebody decides to clean out a lab. Sometimes businesses have sales or auctions. The nice thing here is that you aren’t limited to consumer electronics.
    I have found it better to just leave things on circuit boards until needed, unless you find hours of desoldering therapeutic. And a critical concern is to avoid burying yourself alive with junk that gets in your way. And I have learned a lot reverse engineering interesting things that come my way.
    This is a close analog to having a stock of metal on hand of you are a machinist. You loose mental momentum driving to the store or placing an order for material. It is great to have an idea and be able to lay hands on parts in just minutes.
    Right now my goal is to get rid of perhaps half of my stockpile of junk. Maybe I can sell 20 pound boxes of junk electronics on Ebay?

    1. I bought a table of miscellaneous electronics at a university auction for $10.
      One of the items was a simply built “rodent respirator” probably used on laboratory rats.
      Another auction attendee offered me a dollar for it and I accepted. A friend of his had recently killed a mouse at work and he was going to “present” it to him.

      1. At the same auction, someone bought an HP server in a half height rack. He took out what he wanted and I helped him lift the (heavy) remains into the dumpster. When the rack was sitting upside down in the dumpster, I noticed it had some neat casters. So, I took those off, and with 4 pieces of 2×4, a piece of plywood and a carpet remnant, I built a furniture dolly.

          1. Ren: UM-Rolla TJ4N? If not, pearl harbor is a big deal for that school’s dorm floor. The yearly party started when the floor was failing out of school and barricaded themselves in for a kegger. When I was a freshman we had about a 50% attrition rate on the floor the first year. Memorable times…I’m just glad I made it out alive. I don’t know if the tradition continues.

  8. If this was a zombie apocalypse, scrounging parts would be a good choice.

    However, as long as Digi-Key and Tayda Electronics are still running, that’s the way to do it. Nothing like getting exactly what you need at a reasonable cost.

    If I tore down old hardware to find parts, I would have to turn myself in to the state labor board for violating the minimum wage law.

    1. The relative values of time, labor and money are very different for different people in different states of their lives.

      To a kid with no steady income, big long summer vacations and an interest in DIY electronics scrounging parts makes a ton of sense.

      When that kid grows up to have a good paying job and a family… hobby time is limited and most parts are cheap.

      Later yet come retirement with lots of free time again but a fixed income.

      Of course this pattern only applies to people living in wealthier, developed nations. To some labor will always be cheaper than money. This can even be true for people who do live in wealthy developed nations however those people probably have bigger life issues they should prioritize fixing before procuring a hobby-parts supply.

    2. “Reasonable cost” is the question. Paying 18$ shipping for some parts only worth $3 is not satisfying. So if the project can take the delay I order at Aliexpress – 100 for the price of one – or try the scrap pile.

  9. Goodwill around here tends to be a little weak on electronics. I think it’s because we have such easy recycling that people don’t hesitate to bring their e-waste to the transfer station. It doesn’t cost anything, or rather it’s already paid for in our county tax bill, so people just do it. The bins with the e-waste get drool-worthy sometimes — I’ve seen piles of server-grade machines in there, and if not for the “No Salvaging” signs and the watchful attendants, I would have scored a few for scrapping.

    1. Depending on the site, get chummy with the employees, and during a lull time (and the boss is not around -you’ll know who [s]he is by that time) they might let you have a grab. And then leave a $ or so for their “donut fund”.
      But if it is busy, move on, they don’t want others to see someone else scrounging.

    2. I don’t think I’ve ever seen a Goodwill that’s strong on electronics. They’re usually about 95% clothes, with a row of shelves at the back that’s filled with dishes, lamps, VCRs, and alarm clocks. The advice to look at second-hand shops is solid, but usually non-chain ones have cooler stuff in my experience.

      I understand that it’s possible to get a deal to get things from recycling centers. You probably have to register some kind of company to do it, though.

      1. I suggest folks try to locate a Goodwill not too far from one of the higher $$ real estate sections of their city. We have one of those in our town, and I’ve found not only tons of printers, scanners, VCR’s, stereo receivers, amps, etc that way but ALSO many excellent working electronics like my latest Onkyo amp, lifetime activated TiVo’s, golf GPS units, professional DJ and sound equipment, etc. And always for just a few bucks each … unless it’s 50% off day and then it’s REALLY a bargain! ;-)

    3. I really don’t get why those e-waste dropoff points don’t allow salvaging. You figure there would be decent money to be made by offering ‘$x per pound’ options (asking a higher price than what they themselves get for the bulk, obviously), with a no-refund-no-replacement-no-complaining clause and, more importantly, a no-harddrives clause to pay lip service to data security considerations.

      There used to be an electronics recycling/processing center in Lachute that allowed guests to rummage through their bins and pay a token amount for the salvaged items and it was best described as a magical wonderland for those inclined to electronics dumpster-diving.
      I came across everything from full-size vintage line printers to busted avionics to computer parts of every vintage and variety. Made it easy to tinker with and find hardware for EISA, MCA or PCI-X machines.

      AFAIK they have unfortunately discontinued this service.

      1. Because they’re frequently raided by people looking for dead computers, who then pretend to be charity organizations that sell refurbished electronics for schoolchildren in Africa. They get the money from the real charity organizations, ship in a container full of broken computers, and dissapear again.

    4. Our local e-cyling company that comes out to offices and picks up stuff has a warehouse where, if you are nice, you can pick up servers for a song. Last time I was there, I bought 2 HP servers, 32 core, 72GB memory for ~$100 US. But don’t expect disk drives.

  10. I went “full Mad Max” during college, and boy was campus nice for trash picking. I got a heck of a nice variable autotransformer from the ’50s that just needed a new fuse and some cleaning (I upgraded it with grounded outlets too). I learned how to drive plain LCD glass displays. I got some Swiss NEMA 23 steppers that I need to turn into some kind of CNC machine. A netbook with a dead battery and no RAM cover, that I use to run a few home automation things. A centrifuge that needed some PCB repair. A waffle maker(!). It was a goldmine.

    1. This. Plus a metal cookie sheet / cake pan to hold and catch parts that fall off. Have a few containers of passives harvested this way – both through hole and SMD.

      A small pair of vice grips or surgical clamps will grab onto and add enough mass to most through hole bits that you can focus your attention on the solder side with the heat gun. The part pulls out / drops as soon as the solder is melted enough.

    2. I’ve had some success removing large or multipin thruhole parts by clamping the PC board vertically and using a small butane torch with a flame-spreader on the backside. Usually I can get the part loosened and out without scorching the board, but if I do, so what?

      1. The ultimate method of PCB scavenging is the wet solder technique. It is far better than using dry heat. I have an electric solder pot I use, but it was pretty expensive to buy. I saw a video on YouTube of a China man who had a dished piece of sheet metal with a gas burner under it, that he had a pool of molten solder in. His setup looked pretty economical to me. But when you are heating boards up like that indoors is not really the right place to do it. Because as you’ve noted it can be easy to scorch the boards, and get fumes. As far as clamping boards go I hold the board with a pair of pump pliers. They have a good hold, and keep my hand up, and out of the molten solder. Then in my other hand I use either a pick, or an angled pair of needle nosed pliers to pull parts off boards. As fast as I can get on parts I can pull them out. The really time consuming aspect of it all is sorting the piles of parts that I make though. It can take me 3 days to sort all of the parts I pull in an hour. I haven’t figured out a way to speed that bit of the job up yet. Though using AVR transistor testers helps.

        1. A solder pot sounds awesome. Sounds like something that a hackerspace could own, if it doesn’t create a liability nightmare.

          For me, I don’t save everything off of a PC board; just the components that I’d be likely to re-use. I almost never save surface-mount parts (unless they’re rare) because my eyeballs are stubbornly set to thru-hole. Also, I don’t usually test a part as I remove it; I store salvaged parts separately from my “good” parts, and test when going to use something. Saves heaps of time ;-) Of the salvaged semiconductors I’ve tested, I found that over 95% are just fine.

      1. You do not heat the components with the heat gun, only the solder side :-) At least for through hole stuff.
        I clamped the board in a vice then grabbed the component (if THT), applied gentle pull and heated the backside. Set the heat gun to 360 to 400°C not full blown 600°C

  11. Yeah, power supplies are usually only one or two dollars at a Goodwill, but it is kind of a grab bag.

    The best are the “UL-listed” ones which have empty spaces labeled for stuff like a fuse…

  12. Goodwill is the last place I would suggest purely on the basis that it is a for profit company. The money they make from the sales does not go towards helping those in need. Their only claim is that they provide jobs to the community. Please make a change to your article as I hope the author can agree that Goodwill is a sham. Salvation Army and Habitat for Humanity are much better places to source your hardware as the proceeds they gain from your purchase goes directly to help those in need.

    1. The entire purpose of Goodwill is to provide jobs to people who would otherwise be unemployable. That’s the service they provide. It’s not a sham, it’s just not intended to be a charity like the Salvation Army. They each have their purpose and help people in different ways.

    2. Why does your purchase HAVE to go to a good cause? Don’t get me wrong, that’s cool if it does. Given a thrift shop that is also a good charity vs a for-profit one in the same community I would chose the charity one first. But why is it somehow wrong for them to exist if they aren’t a charity? They serve as a bridge between people with stuff to get rid of and people that need or want that stuff. What’s wrong with them getting paid for that?

      Besides… Keeping shit out of landfills for a little while longer IS a good cause all by itself!

    3. So because the name is Good Will the money has to go to those in need? Taking things a little literally, aren’t you? I don’t expect every dollar of my purchase to go to Colonel Sanders retirement fund everytime I get a bucket of chicken.

      Not sure how to tell you this, Jean Luc Picard, but if we stopped shopping at every store that was looking to make a profit, there wouldn’t be much left. Not taking anything away from companies that wish to help those in need, but deciding where we spend our money solely on that fact seems preposterous (and unsustainable).

    4. In my experience, the Salvation Army provides vital and much needed services to the poorest and most destitute in the community, and they do so without regard to the religion or sexual orientation of those in need. And beyond saying a prayer before a meal or holding services for any who wish to attend, they aren’t ramming a religious agenda down anyone’s throats. They’re also fairly efficient; most of the donations make it to actual service.

      As far as “Christians” go, the Salvation Army are about as far away from Roy Moore as it’s possible to get.

      I’m not religious, but I’m quite happy giving money to and supporting the Salvation Army. Until we finally agree that we all share the responsibility to aid and support the poorest among us, we need groups like them.


      1. “And beyond saying a prayer before a meal or holding services for any who wish to attend, they aren’t ramming a religious agenda down anyone’s throats.
        Being required to say a prayer before a meal” is AT LEAST “ramming religion down the throat”. I mean: “Praying to what entity?” – I don’t believe in a god.
        But when I want to get some parts religious or charity stuff is my least concern. I buy it where t is available and/or cheap

    1. Ah, so you are well down the same road I am on. Indeed, I probably have a dozen in that range in one handy box I can think of and many more on PCB’s elsewhere. As I have said, I now find it saves time on both ends to just leave parts on PCB’s until they are needed. Faster to scan boards for what I want and no more desoldering sessions to depopulate boards. I just sort into major categories: logic boards, analog boards, and power boards currently. Intact power supplies go into another box. I have a couple of big boxes full of wire, connectors and harnesses that is endlessly useful.

      I suppose it depends on brand, but cheap consumer electronics would be the worst place to get parts, especially electrolytics. Quality computer gear that isn’t consumer oriented is what you are after.

      Took me less than 2 minutes to have a 1000 uF in my hand (but what working voltage?) Every electronics hobbyist needs a decent junk pile. Mine is a 1000 uF 10v Nippon Chem Con. For some reason I have lots and lots of 2200 and 1000 is sort of rare. Here is another one that looks like a fossil 1000 UF 25 volt Computamite. Ah, and here’s another …..

      1. I’ve had to exercise some discipline regarding how much stuff i keep, to avoid becoming a pathological hoarder. My current rule is that if i snag something (roadside/dumpster), it has to be immediately useful (after a small fix maybe), or I have to salvage parts ASAP, so I’m not just storing dead equipment. Fortunately, I find the disassembly quite therapeutic, and it’s easier to keep 4 containers of sorted parts than all the dead equipment they came out of.

        1. This… once I had a pile of dead motherboards that would easily occupy a 1000mm×1000m×400mm space. (Some were old server full-ATX motherboards… PII era.)

          I went crazy with the heat gun, just hitting the PCB in spots until the board blistered and the parts dropped off (many were SMD). Those parts now sit in small plastic boxes that take up about 400mm×300mm×100mm.

        2. On the other hand, some things are worth keeping together. Those switching supply arts, if you need one you may get by using the whole thing. Radio type parts may make use of the IC or peripherals parts if you use any of it. Plus, the original circuit gives IC pinout, or other details. Not for everything, but sometimes.


    2. Yeah, I did my testing with 10x 100uF caps, and if it was a real desert island kind of thing that would have been OK. But I was trying to have a slightly more professional final result.

      Well, as “professional” as old parts taken out of a VCR will allow, anyway.

    3. 1,000uF is kind of expensive to buy by-the-bag new just to have in stock. It also is likely to be electrolytic which means salvaged or even new-old-stock components are kind of suspect. Soldering a bunch of small ‘decoupling’ capacitors in series sounds good on paper but there will be parasitic inductances that will likely prevent it from functioning as desired.

  13. I ran into this problem years ago and kind of solved it. What I’ve done is tried to create a selection of various size and voltage of capacitors that I can use as general purpose replacements. physical Size of the capacitor is my biggest concern, often times I find if I need to replace say, a 100uF @ 16V in something and trying to squeeze a 100uF @ 25V in is difficult, so, running extra long leads or moving a few things is needed. I’ve even found scenarios where an exact capacitance and voltage rated replacement isnt a drop in replacement when it comes to size.
    Overall, I try and keep a decent assortment of values and voltages on hand in advance. this covers about 50% of my repairs.
    Another decent source, if you have one locally and you can get past the @ssholes in charge are trash dumps or recycle centers.
    People throw away old electronics constantly, especially old TVs. Nothing wrong with them, everyone simply wants the flat screens now. Getting the PCB out and ditching the rest takes up less space. Getting the @ssholes who run these places to let you have them, that’s a different story. At one time, I could get them for free or pay a few bucks to the guy to let me have it.
    I used to get flat screen TVs from the trash dump, fix them or use the parts out of them. Now, I cant even sacrifice a damn goat to the @ssholes in charge to get even a damn cable.
    Was also a great place for getting parts for washers and dryers. Those controls and elements are not cheap when they need replacing.
    This really hits a personal spot with me, as my father in law works at one of these places and I’ve pleaded with him many times as to why they are sooooo damn protective over junk.
    He can bring a rusty piece of sh!t bicycle to my house for me to fix up for the kids (yeah, right….) but, no, cant part with any of those TVs, against the law, against the rules!
    “What law?”
    Needless to say, I keep an old phone book around to hand him when he needs something repairs now….

    Last time, I was dropping off some older electrical stuff, I saw a clump of cables and grabbed them. Locally in my area, I’ve seen them use people having to do community service as an assistance, kind of sucks when some big, dumb d!ckhead who wont be there in another week comes up and accuses you of being a thief for stealing some cables someone else threw away, and then see the large truck pull up 5 minutes later, grab the bin, tilt it while lifting it in the air, and seeing everything sliding/crashing/breaking inside……

    I digress……
    anyway, my point being, if you do happen to have one of these places locally, it may be worth taking a look, see if there is such a place for electrical stuff, how easy it is to access, or, worst case scenario, actually trying to befriend someone there or slipping them a few bucks to get access to it. they don’t make enough money to brag about, and a little money thrown their way really goes along way depending on what you have access to.

    1. yeah, my neighbour and I have been warned a couple of times now at the dump not to pick up when we drop off ;-)

      There are a couple of chain stores here who have open bins in their parking lot for customers to recycle. Nobody bats an eye if I take something out, so i can still check those occasionally.

      It’s amazing what people will pitch: wall warts and power supplies, IEC line cords, perfectly good USB cables…

    2. Yes. Even fifteen years go I was getting interesting things at rummage sales. My barely used HP4P laser printer was fifteen dollars at the local Rotary Club garage sale. But a lot of those sales have stopped. Electronics has become more common, and they can’t make money from most people if it doesn’t work, but checking it often requires skill, and among a volunteer pool, that may be lacking. I suspect people were umping broken electronics at such places because they didn’t know what to do with it.

      So “ewaste recycling” gets it. I’m seeing less electronics lying on the sidewalk, so people are learning to “dispose if it properly”. But like you say, it’s not limited to broken items. They just want it, or they’ve decided it’s “obsolete”. Before, it would have a chance at a second life, now that doesn’t happen. So it could be a collector’s item, or something esoteric (I got a Grundig Satellit 700 portable shortwave radio, top of their line when new, for $2.50 at the Rotary Club sale about 2007, nobody really knew what it was), or something to keep an old computer going, or something that someone without money could still appreciate (lots of digital cameras that simply lack megapixels).

      I fear that other than obvious items (iPads and recent computers) won’t be offered a second life. The value is in the gold and whatever they can offer. People may also take it to recycling because it won’t see secondary use, some are fussy, they don’t want other people having their stuff for free. Someone speculated a few years ago that it’s really business that likes the recycling, if I can’t get a used GPS for five or ten dollars, then I’ll have to pay full price. I certainly wonder why some food place would offer a free item if you bring in an MO3 player or something worth more than the slice of pizza.

      It would be great if the public had a chance to take what they want before it’s hauled away. I am tempted to stand around when there’s a collection, hoping to intercept things, but figure I might be run off. The system us for the average person, not only would they have no use for broken r old items, but thy might nit get it back into the ewaste system when it doesn’t work.


  14. I was lucky enough to be in the right place at the right time when a couple electronics shop were closing, so I got an almost lifetime supply of ICs, transistors, TV parts etc. Regarding capacitors, chips or expensive transistors, I only get them online from reputable vendors or NOS from surplus stores: cheap chinese sold online are all junk, all IC/bjt are relabeled fakes. Do not expect to purchase a thousand 2N3055 (power BJT), 2SC1969 (well known spare part for CB radios) or NE5532 (low noise opamp for audio) on Ebay/Aliexpress and hope to get even just a single genuine one. Chinese resistors and inductors are usually ok, a bit cheap in materials (thinner wires) but they usually work and are accurate.

  15. When I was a kid, the first few projects I carefully copied the parts list to a sheet of paper and went to the store I’d found in the Yellow Pages. Kind of expensive, I knew so little I had no choice. And they didn’t work. Some of it had to be my lack of soldering skill (it was a wood-burning iron) but I wouldn’t have known if the replacement parts were suitable or had different pinouts.

    Things started working when I started taking things apart for parts, including 99cent boards from the local store that were for driving Nixie tubes. Twisting the very short leads together ensured the problem wasn’t my lack of soldering skills.

    But it meant I’d progressed, learned enough to scrounge parts and save money. So I’ve always done it.

    There was a period 20 years ago when I’d find early cellphones for a few dollars, those were loaded with interesting RF parts, but also there was less integration, so familiar ICs like the NE570 compander and CPUs, and mostly through-hole parts. I’d carry a few tools around so I could grab specific parts if needed. Power transformers can be expensive, and variable capacitors less available, so sometimes just pulling those were worth it.

    About ten years ago I got an “earlier” Powerbook, which came with no power adaptor, it needed 24VDC. I remembered that printers often had higher voltages, and the first inkjet I opened had the needed voltage, and on a separate assembly.

    We’ve lost the window for some things. Fewer radios around with variable capacitors. Most power supplies are switching, so it’s easy to find power supplies, but fewer transformers for making linear supplies. The clunky cellphones have dried up. I rarely see tv sets with analog tuners, less of a chance to find RF MOSFETs with leads.

    Fast mailorder is a relatively new thing, certainly in Canada there weren’t many places that would deal with hobbyists. Scrounging parts was not just a way to save money, but also to have a local source. Plus, it forces you to know the parts, what’s needed and what will work. It did dazzle the kids in high school when I could pull out a part and say it would be fine.

    But I’ve been thinking about my distant cousins I’ve never met on the Colville Reservation in Washington State. I’ve never been poor but never had enough money for books and hobby items. But I’ve always been able to find books used and scrounge parts, because I live in a big city where they are plentiful. In a more rural area, especially if there aren’t people with money to easily discard things, I’d not have had access to such things. That can be a real burden, imagine the smart kids who can’t pursue things because they have no money and no access to the junk we have in cities. Their limitations aren’t intelligence but lack of resources.


    1. I never joked about Radio Shack. I did grumble that too many of them turned into computer and phone stores, but there used to be one near me with a good parts selection, from resistors up to Arduinos. Gone now of course. Drat.

  16. There are some good walk thru’s on the radio repair sites on slowly stabilizing those old catalytics. Should do a glance, just so you know how to dial them back up. They say most of the old caps will work fine, as long as slowly brought back up to load.

    I had to get rid of loads of stuff for parts, when lost a storage spot. Ended up opening cases, pulling power supplies, battery holders, and connecting cables, and pitching most of the rest.

  17. I’m spending time getting rid of my father’s collection of parts. Thousands of vacuum tubes, most worthless but some sell for over $100 on ebay. Scavanged resistors and capacitors are going in the trash when I get to them.

      1. A widow at church said the next time I stop by, she’ll let me have her late husband’s TV vacuum tubes and (vacuum tube) test equipment. I’m afraid that if I take her up on the offer, my wife will be the next widow.

        1. Hit your wife with a plan: any working test gear will be a keeper, you will either fix, strip or recycle the non-functioning stuff in a short time period, and you will cherry-pick the tubes and ebay/hamfest/recycle the rest.

          When my wealthy uncle passed away 2 years ago and my aunt was downsizing, they offered me first pick of his top-end stereo equipment. ReVox, Thorens, Altec-Lansing…

  18. I live in the Chicago land area, there are many Good will stores around here…
    My hot tip is to shop in the rich neighborhood(s), trust me the electronic goodies out of Wheaton or Naperville are better an cheaper than in other locations…
    My experience anyway…


  19. You’d want to be very cautious about reusing old electrolytic capacitors. I haven’t seen it but there must be a list somewhere that shows the average time to failure for different electrical components, and their shelf life. Some obviously last orders of magnitude longer than others depending on the materials used to construct them, and their source.

    1. But he was able to finish the project. He can make a note, so he knows it’s a reused electrolytic. And if course, some if the issue is electrolytics dealing with high frequencies in switching supplies and digital motherboards, 60Hz won’t affect the electrolytics so much.


    2. Electrolytic capacitors have a lifespan of between 1,000-20,000 hours depending on the quality. To put an old electrolytic capacitor back onto service after it has been lying around for a long time you have to perform a process on it called, “reforming”. This is slowly increasing the current through the capacitor to rebuild the oxide layer on the foil. I have reformed decades old capacitors and brought them back into usable spec. But I do live in a rather damp part of the globe. I’d say now the best vintage capacitors available would be of Japanese manufacture. I think all of the western caps today would be so old they’re shot. Rubycons are the best. I’ve seen 40+ year old Rubys that still work. But I did just recently have to toss an old Ruby out too. It was reading as a resistor. So it was gone. It goes without saying that you should test any old part you are going to use in a new circuit.

  20. I live in darkest africa where I am a 3 hour drive from nearest town. I have a store room referred to as “The Archive ” where I store all my old junk that I might find useful . Strip down as much as possible eg: computer power supplies strip out boards and place together in box and same for fans etc.Space is a precious commodity. Do an annual evaluation and toss stuff. This also helps to keep you up to date with what you have and some good ideas come out of it .I love a good electronic shop which are hard to find now days but always on the look out. Was in London recently and popped into a Maplin that I was passing and found blister packs of Capacitors, resistors of various values and some rf adapters . Could not help myself.
    As I am the only electronics guy in the area it can be a lonely business but do provide a service to the local community.
    More fun than profit.Funny how peoples eyes close when you mention what fun you had fixing an inverter welder or how you manage to hack into an unsecured wifi 2km using an old satellite dish. Pity electronics and software coding seems to be uncool these days.

    1. Oh no, it’s still very cool.

      I bet HaD would be interested in an article about the hacking going on in darkest Africa, and to what extent technology is affecting that part of the world.

  21. When I pluck parts I only have to pull the Weller gun out of it’s holster and seconds later parts are free. I don’t see how anyone can live without a gun (not a NRA endorsement). Ever try to reflow the middle pin that is connected to the case on a regulator that’s mounted to a heatsink with a pencil iron? I have seen so many self desoldered regulators on boards that crash, they didn’t get hot enough to begin with in the wave.

  22. My favorite thrift is a St. Vincent depaul where stuff that isn’t good enough for the fancy stores ends up. DVD players and VCRs can be had for $5. Tons of other stuff shows up and you can get everything at flat rate prices – usually under $10.

    I fix vintage stereo equipment and arcade machines so I need fresh electrolytics for pretty much every repair. There is no effing way I would use salvaged electrolytic caps in any repair. I want my repairs to outlast my sorry ass and using unknown manufacturer 20 year old thermal stressed components is a recipe for disaster. If you can’t stay focused on a project long enough for a parts shipment then you should ask your doctor about Adderall(tm).

    As for my salvaged parts story – how about this lovely turntable that used control switches salvaged from a hairdryer?

  23. If you’re after capacitors, has anyone tried the replacement for XC condensers? They’re the AB-619 units from the Electronics Dept, Unit 16.
    They are rated to 33 thousand volts and no leakage.
    Send a teletype to Pete Knowles at Supreme Equipment, it will be handled from there. Free delivery and zero invoice!

  24. I’ve had people make fun of me for saving the stuff I do. The same people come and ask me for things on a regular basis.

    On another topic, here is a hot tip. Next time you tear something apart with a motor, take a look at the PCB near the motor connector. Often there is a section of the board you can chop out with your tool of choice and is a fine motor driver, ready to go.

  25. I remember arguing with people in the comments regarding the merits of having a brick and mortar store around. So many people seem to think that idea is outdated now that we have cheap internet goods with free shipping. Now the Rat Shack is finally gone and here’s this article!

    If you do have a shop with components near you… why not try to get a few of your parts there now and then? Enjoy the browsing while you are there, maybe even talk shop with the owners a bit. If we all do that maybe we can actually have nice things like electronics stores again!

    I’ll tell you this… walking around the mall Rat Shack was a lot more fun than watching my wife look at clothes!

    1. I refuse to subsidize brick and mortar stores. I believe in a free market economy too much to justify that sort of thing. They either compete, or they die. That’s why our system is superior. We have less inefficient waste.

  26. I have nothing against someone buying something from a thrift shop to pull a part out of. Hey.. at least something of it escaped the landfill. But.. throwing out all your stuff… finding you need a part… buying something from a thrift shop just to get that one part.. and writing about it…

    I would hope for at least a mention of the idea that maybe throwing out ALL your stuff was a mistake! Sure, thin it out from time to time but please, don’t make buying whole devices just to get a single capacitor become normal, everyday procedure! That’s so wasteful!

    1. It’s not really that wasteful. (and no, he didn’t throw out all of his stuff)

      First, if the unit is curbside, a recycler, or the dump… it’s already been disposed of. If it’s at a Goodwill, maybe it’s still functioning, and worth leaving for someone else. But if it’s broken, dirty, or incomplete… it’s probably not going to be reused.

      Second, when I tear apart something, I finish the job: the plastics end up in one pile, the metal in another, the PC boards and wires in another, and you can bet that i usually pull out anything useful like hardware and power supplies. These sorted piles are then disposed of with the people or outfits most suited – eg sorted metal to a metal recycler. So I’m performing part of the recycling disassembly process.

      And finally, if I go to the trouble of fixing or pillaging from other people’s equipment, you can bet that i also get extended use out of anything I buy new, and I am not likely to throw out good stuff as often as most other people.

      1. If I pre-disassemble/sort my electronics before bringing them into the county recycler, they often waive the e-waste surcharge. The circuit boards go straight to their bin, and the metal goes into that bin, it is the remaining plastics I have to pay standard fee.

      2. “(and no, he didn’t throw out all of his stuff)”

        – per the article –

        “At that point I’d usually go through my collection of junk electronics and computer motherboards, but I had recently gone through and tossed the stuff that had been laying around for as long as I could remember.”

        ” If it’s at a Goodwill, maybe it’s still functioning, and worth leaving for someone else. But if it’s broken, dirty, or incomplete… it’s probably not going to be reused.”

        – did we read the same article –

        “Desperate times call for desperate measures, so I got in the car and took a ride to the only place I knew where I could by electronic components for cheap: Goodwill.”

        “So I’m performing part of the recycling disassembly process.”

        Awesome! Recycling is usually better for the planet than landfilling and using new resources. But it’s not perfect. Re-use is better than recycling.

        Recycling materials involves transporting them to processing plants, then to factories finally back to warehouses, stores and homes. Your recycled material has probably traveled 100s if not 1,000s of miles before it is put back into use somewhere. That is a lot of carbon. Also, large amounts of energy and/or chemicals are used in processes such as melting and purification. Fumes are released into the atmosphere.

        Simply selling the item to a local who plans to take it home and use it rather than recycle it into something new is almost always WAY better! The exception being when the old item is really really energy inefficient compared to a newer design. It takes a lot of inefficiency to offset the environmental cost of all that recycling though.

        Now again… don’t get me wrong. I’m not trying to be too critical. Buying an occasional thrift shop item just for a part is fine. Ultimately they probably wouldn’t all sell anyway. What I was more responding to is that there seems to be a bit of a movement among “hackers/makers/diyers or whatever” to stop keeping junk boxes, throw away all the scrap and just buy everything as needed. This is really wasteful and bad. It turns what should be a positive way of reducing consumption into something even more wasteful than just buying things new and ready made all the time like everyone else!

  27. I love scavenging items for reuse and two years back used some to build my battle robot. Parts included wheels from a vacuum cleaner, cordless drill motors, a pulley from a tape recorder, spikes from old printers (a great source for motors BTW – I find them fascinating), old tent support frames, and even ball bearings. Interestingly I got oone ball bearing from a large photocopier and one from a child’s scooter and they were exactly the same. In retrospect I should not have used the one from the scooter though due to wear and tear. Still it all worked. I was also lucky in that I asked for permission to take stuff from the local bring in site and it was granted. As a result I collected various printers, DVD players (for the motors I hope to use for a small drone one day) and for their lasers, photocopiers, and even some music mixing equipment with sliders (I suspect the electronics in this would be of very good quality). Of course, as a beginner to electronics, building the robot involved many wrong turns and much money.. But I don’t regret one moment as actually building something was a fantastic life changing experience. Feel free to ask if you want more details of my robot. And btw I love this site!

  28. I do find it strange how long online orders take to ship in the US. I was in California (which is supposed to be, you know, the future) visiting a friend and I needed something, I ended up paying for ‘express’ shipping which was 3 days! That wouldn’t fly in the Uk where standard delivery from most places is next day if ordered by 7pm (or later for Amazon). Some stuff comes same day! I need stuff while my diminutive attention span is still… Ooh squirrel!

  29. I have noticed that Maplin, the UK high street component stockist has just refitted my local branch. They have done away with the component counter and focus on cheap crappy RC toys and other consumer rubbish I can get anywhere. Haven’t tried asking them for capacitors yet, I now have a hoard that should last a few years :)

  30. DARN you hackaday! Here I was thinking that my salvage supply one-stop-shop was going to forever supply my salvage needs, when in order to even approach my diverse parts cache, my peers would be required to rummage the local dump for for hours on end. Now the secrets out, and you’ve ruined it for everyone. Thanks alot.

  31. A good source of parts is found in the volunteers of America and salvation army stores. For example a vcr or a am or fm radio at a dumb price of 3 or 4 dollars, you know that at that price it don’t work. One that sells for 19.95 will work instead plus as is items. They have an excellent take apart items that you can get cheap with many components to add to your inventory for needed projects.

  32. I live within driving distance of SparkFun and there is a lingering RadioShack about 15 minutes away. Though the RS has a pretty dim supply. There is also a microcenter that has a few passives.

  33. I got my start using parts scavenged from old TVs and stereos found in the dumpster of the local appliance store (which is where you bought that kind of thing in the ’70s). I built my first projects using mostly scavenged parts. I built my first audio amplifier using all scavenged parts. Class A, a horizontal output transistor and a 10 ohm resistor, large electrolytic to isolate the speaker from DC. Quite a rush.

    I learned to sight read the resistor color code because I had boxes full of resistors to go through. I was too impatient to slowly sort them all and put them in labeled boxes or envelopes.

    Surface mount parts are difficult to scavenge. I will still scavenge ferrites. I just did a class at the local makerspace, OlyMEGA, on building the Joule Thief, using all parts scavenged from CFLs.

    I have scavenged some 20uF ceramic capacitors. Surface mount, but easier to remove due to their size. Otherwise a bit expensive. I’m building a few things that require VERY low ESR power to support high current pulses, so a array of these and some low ESR electrolytics are going onto the PCB close to the parts. One is to test the saturation flux of ferrite cores. The power supply must not sag or it will screw up the reading.

    If I were building this for sale, I’d use all new parts.

  34. blarsblarson, I’m interested in the scavenged parts and hardware(as I belong to an antique radio/electronics club-and we’re always looking for parts and even TV tubes; there are a few home brewers among us) Will gladly pay shipping to Phoenix.-Bruce Thorpe N7MMR

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