Tuesday, March 27, 2012

How I Store My Electronic Components

It's not an unusual question to arise in the electronics community. Piece by piece, you've been buying components and equipment, until one you turn around and find yourself knee-deep in tiny boxes and ESD bags, and you spend more time of each project looking for parts than putting them together.  Everyone goes through these growing pains in the hobby, so I figured I'd document my (partial) solution.

I finally got fed up with having to move 4' piles of boxes around to be able to get into my closet and bathroom throughout the day, so I broke down and went to Ikea and bought their tallest, deepest, and cheapest bookcase, which if memory serves is the deep Billy in white.  The vast majority of this bookcase is dedicated to electronics, with only the very top shelf handling some overflow from my (extra-curricular) textbook bookshelf.
Starting at the top, the top shelf is pretty irrelevant.
  • My back-issues of Make Magazine.
  • 1800 Mechanical Movements (A great puzzle book)
  • Misc very old chemistry, metallurgy, and welding texts which I would be hard-pressed to find a copy of for you, let alone a reference to online.
The second shelf is all of my electronics texts.  I have almost as many books on programming, but they're across the room.
  • The Temperature volume of Omega's catalog.
  • AdaFruit's 0603 passives kit.
  • Texas Instrument's TTL Databook, which at one point you could buy in their eStore for $0.10.
  • Several 1940's era radio books.
  • Terman Electronic and Radio Engineering. Supposedly one of the best vacuum tube texts.
  • Design of Analog CMOS ICs.
  • Advanced Digital Communications.
  • Teach Yourself Electricity and Electronics.  This was actually my very first electronics book, which my father bought for me at Halted back when I was in middle school.  I will say that it is likely that much better books for beginners, and particularly young beginners, have become available in the last decade since I got this book.
  • TTL Cookbook - Lancaster: It is a rare EE's bookshelf that doesn't have, or at least seen, this book.  It is a classic in building pure-logic circuits. It took little more than this book and a tube full of 7400 logic for me to build my own clock.
  • Noise Reduction Techniques in Electronic Systems - Ott: This book is quite sophisticated, so I wouldn't say most people need a copy of it.  I would suggest that you at least borrow it at one point and read it through once to get an idea of what to think about and look for in sensitive systems.
  • The Art of Electronics - Horowitz: If my apartment was burning down and I could only grab one book, this is it.  A great text on electronic design.
  • The ARRL Handbook: I've always been underwhelmed by this book.  I have both the 2009 and an early 1980s edition, because they took out all the tube pinout tables in the 90s.  They release a new edition every year, but the 2009 section on computers and wireless networking still read like it was written in 2001, so I don't really understand what they're changing every year.  Incredibly, I know Hams who buy the new edition every year, so you can get a good deal on lightly-used copies that are only a few years old.
  • Technician, General, and Extra amateur radio study guides: These never ended up being as useful as I ever thought they would be.  The only thing I ever refer back to in these is the color-coded radio band charts, which guess what, you can get as a PDF online.  Borrow these from someone else, pass the test, and give them back, in my opinion.
  • My back-issues for QEX, which is an outstanding bimonthly magazine put out by the ARRL.  It's thin at only ~20-40 pages, but I find the three articles this magazine does have are always more interesting and challenging than anything I see in Make or QST.
 Now we're getting into the meat of my system.  Below my books is an empty shelf which I use as the dumping ground for projects so they don't collect on my workbench proper.  Breadboards, grab bags, etc.  With some effort, and probably female pressure to be more organized, honestly I could probably get everything on this shelf to fit in somewhere below it, but luckily I'm lazy and single, so this graveyard lives on.

In some ways, it's easier to find common parts by stripping them off the last project than putting them away and digging them out again, so I tell myself that this is still an integral part of my system.
Finally, my junk box (using the singular form of box loosely).  My collection originally fit into a single corndog box, which is really nice for the job with the locking lid and everything, but as you can clearly see, I've outgrown a single box, and am close to outgrowing this system entirely.  Whatever I do end up replacing it with is going to require numbered boxes, binders, and spreadsheets, so I'm trying to make this work as long as I can.

The system is based on starting with your first box, which you simply dump everything into.  Each little ESD bag must be well-labeled, with not just the part number, but also a short description of the part's function, quantity, package, etc. Once all of these bags stop fitting in one box (which happens quickly), you get a second box, define a new category, and resort everything until you outgrow another box and have to split things again.  In rough chronological order of how I split my junk box:
  • Passives: through-hole resistors, capacitors, inductors, diodes, etc.  I also have some small spools of magnet and wire-wrap wire in this box.
  • ICs: Through-hole integrated circuits.  This includes shift registers, 555s, EEPROMs, and some assorted 7400 logic which doesn't fit in the several 3' tubes which I store most of my pure logic ICs in.
  • Analog: Through-hole analog ICs.  Voltage regulators, op-amps, maybe ADCs and DACs if you like them in here more than in ICs, audio amplifiers, etc. 
  • Modules: All of the large pre-built modules.  LCD displays, GPS receivers, RFID readers, segmented and matrix LED displays, etc.  Use lots of small bubble-wrap baggies in here to prevent scratching screens.
  • SMT: The surface-mount equivalents to the IC box.  In addition to these, I include all of the breakout boards I've collected over the years in this box (i.e. Electroboards).
  • SMT-PASS: The bulk spools of surface mount passives, which I only need to refill my AdaFruit book when I deplete a strip.  When you're buying individual SMD passives, it almost always makes sense to buy them in quantities of 1,000+; pricing is usually logarithmic, and you often find 2,500 count spools at swap meets for $2 a piece.  Trying to get parts off the spools is a pain, so cut off a few strips of 25, label the back, and put the spools in deep storage.
  • Connectors: Male and female board-to-board header, DB-9/25, crimp spade lugs, thermocouple jacks, IEC jacks, terminal blocks, solder tabs. If I didn't have a toolbox dedicated to nuts and bolts, those would probably end up here too.
  • Packaging: Project boxes, perf board, ESD foam, other misc cases and packing material I've collected.  I also keep about 20% of the expanded paper I get from Digikey, but I use it to pad behind all of the boxes to keep them towards the front of the shelves where I don't have a second row of boxes.
  • Microcontrollers: Nothing but microcontrollers, both SMD and THR.  Between AVR, MSP430, PIC, ARM, and 8052, I've got enough different microcontroller chips floating around I could build a beowulf cluster powerful enough to crack the Enigma. Each architecture gets their own sub-bag inside of this box to make digging easier.
  • Mechatronics: motors, encoders, servos, switches, strain gauges. If it moves and has to do with electricity, I put it in here.
  • Batteries: AA, AAA, and CR2032 blister packs and various geometries of battery clips. It's nice to have a variety of configurations of clips (2 in a row vs next to each other, integrated power switch, etc) when you're working on a project and need to find some way to fit a battery in what little space happens to be left.
  • Project Specifics: Some projects require some very strange parts that I never stand the chance of using in anything else, or I plan to be building so many of the project that having everything in one place will save time.  The GoodFET, Bus Pirate, and SerialCouple all get their own homes.  I also have a few boxes which are parts not for me, but which someone I know has asked me to order; it's much easier to not lose their stuff when it's taped up back in a box with their name written on it.
Really, the entire system comes down to trying to keep boxes below ~30-40 parts so it's easy to root around in a single box and find a specific part, and when you're later deciding which box to put a part in, ask yourself "which box will I expect myself to have put this in next month?"  If I want a voltage regulator, I know to look in the analog box, and when I want a motor, I look in the mechatronics box.

The one problem that my system doesn't solve is inventory tracking.  I can find parts pretty quickly if I know I have them (and actually do have them), but I have no good way to track if I own a part, or how many I've bought or used.  I have double-ordered parts I'd forgotten I had before, which in the 3-5 quantities I usually order isn't a big deal, but double-ordering a 5,000 spool of 330 ohm resistors would hurt my dignity.  At some point, I will probably need to put together a spreadsheet tracking inventory, but as it is, this system is fast and easy enough that I actually use it.

Sound off in the comments with your own organization schemes.  Internet points to be awarded to the first person who can produce pictures of their entire (non-trivial) electronics inventory in a single giant refrigerator box with "junk box" scrawled across the side.

3 comments:

  1. I definitely don't have that many parts yet, but have been working on an organization system as I go along. Finally got all my resistors sorted sequentially in #1 coin envelopes with labels for each envelope. Originally I was going to use a couple index card boxes to store them but ended up modifying a cheap toolbox instead to hold them all with room to spare for other similar components.

    http://a.yfrog.com/img875/3644/e4btos.jpg

    ReplyDelete
  2. Dang those labels are nicer than the hand-written notes I got. I finally broke-down and ordered an actual 1/4W resistor kit to flesh out my piece-meal collection, and I think I need to make a new set of coin envelopes when I get back to Davis.

    ReplyDelete
  3. I just used the PDFs from this site and edited them in Inkscape a bit. I put the SVG files up here if you would like them. I just opened them in Inkscape and copy/pasted the value/color units into an Avery template for Word.

    ReplyDelete