Ask Hackaday: Preserving Electronic Devices

Conventional wisdom holds that we no longer make things to last for the long haul, and that we live in a disposable world. It’s understandable — after all, most of us have a cell phone in our pocket that’s no more than a year or two old, and it’s often cheaper to buy a new printer than replace the ink cartridges. But most of that disposability is driven by market forces, like new software that makes a device obsolete long before it breaks down, or the razor and blades model that makes you pay through the nose for ink. It turns out that most electronic devices are actually pretty well engineered, and as long as they’re not abused can still be operating decades down the road.

But what happens when you want to put an electromechanical device away and preserve it for a rainy day? What can you do to make sure the device will operate again a few years down the road? Are there steps one can take beyond the typical “keep it in a cool, dry place” advice? In short, how do you preserve electronic devices?

The Problem

I’ll admit that there aren’t a huge number of devices that are worth the extra effort that would go into storing them for future use. But I have a specific piece of gear that I’m looking to put into storage: my daughter’s old insulin pump. We recently started having some trouble with her pump, an Animas Ping that has been a solid performer for over three years. They seemed to be software issues, minor annoyances that the manufacturer couldn’t seem to resolve despite replacing the unit outright twice. We decided to try for a pump from another manufacturer through our health insurance, and after a flurry of letters and phone calls, a new pump was approved.

The device in question: her old insulin pump. Note the time — the RTC died within a week without the battery.

But now I’m left with a conundrum: what to do with the old pump? Hacker me says, “Teardown!” There’s certainly something to be said for what I’d learn by looking under the hood, but responsible adult me sees this as an opportunity to have a backup for the new pump. As we learned with the first pump, these devices are far from perfect. Diabetics using a pump have to keep a backup supply of needles and syringes ready to deliver insulin the old-fashioned way in case the pump fails. But it’s a difficult and traumatic transition, especially for a kid, and having a pump around that could be put back into service quickly would be great for our peace of mind.

With that in mind, I’m left with the question of how best to preserve the old pump in top operating condition. If it were something as simple as an obsolete cell phone, you could reasonably expect to just toss it in a drawer and be able to boot it up again in a couple of years after charging the battery. But this pump is an electromechanical device with a finely calibrated syringe pump driven by a tiny but powerful gear motor. There are moving parts in addition to the electronics, all of which need to work together.

There’s also the wrinkle that the pump does not have a rechargeable battery — it runs on a single lithium AA battery. There appears to be either a supercapacitor or a small rechargeable internal battery to maintain the real-time clock, which I assume is topped off from the main battery. There’s also the question of how the pump’s setting are maintained — I assume there’s flash memory of some sort in there, in addition to the pump’s firmware.

My Ideas

My basic approach to preserving this pump will be to store it powered down. Leaving batteries in devices for extended periods is never a good idea, and a leaking battery is likely to be fatal to the pump. Plus, this device expects to be doing something when it’s powered up, and if there’s no insulin to deliver, it starts to whine. I’ve already left the battery out for a week and seen that only the real-time clock resets; all the other settings are preserved. I’m going to slowly increase the time off-battery to a month and see what sort of issues arise, if any.

If I can get to a month unpowered, I’ll put a reminder in my calendar to pull the pump out of storage and give it a little exercise. My experience with electromechanical systems like 35-mm cameras is “use it or lose it” — mechanisms need to move once in a while to keep everything working. So maybe I’ll put the battery in once a month and give the pump a little workout, moving the plunger back and forth a few times to make sure everything is still working.

Your Turn

Those are my ideas for now. But here’s where you get to pitch in. How would you put a device like this aside for a rainy day? I realize I may be going overboard here, but keeping in mind that this is a vital piece of medical equipment, a little extra care is probably prudent.

Or perhaps you think I haven’t gone far enough. Either way, sound off in the comments below. And if you have any experience stashing gear for the long haul, by all means share your story. I have a feeling that there might be some interesting tales out there about not only the hows but the whys: what would make you go to the effort to preserve something electronic?

62 thoughts on “Ask Hackaday: Preserving Electronic Devices

  1. “In short, how do you preserve electronic devices?”

    Stasis field. :-)

    “I’ll admit that there aren’t a huge number of devices that are worth the extra effort that would go into storing them for future use.”

    Wonder if anyone would have had the foresight to preserve an original Apple?

  2. For any extended period of time the failure mode will be EEPROMs and other stored charge memory devices. I’ve had failures in 20yo devices that I’m still using. Automotive ECUs, in this case.

    1. If I lose the settings in the pump, it’s not the end of the world. I have a printed copy of the settings and can quickly enter them using the pump UI. No need for a computer or special software.

      If the firmware on the pump dies, though, then it’s a brick. Nothing I can do about that, really, unless a Faraday cage would maybe help prevent stray RF fields from causing any issues.

    2. Specifically EEPROMs: I don’t think I’ve seen any devices where retention wasn’t for less that 10 years (most are 20Yr, if not 40Yr). This is for unpowered storage at 25C (77F). Retention falls as temperature rises, so storage at 50C(122F) would decrease to 8Yr for the 10Yr example.

      There aren’t that many electronic devices that would valuable enough to keep running more than 10Yr. Most get replaced for new features if they haven’t failed by that time. Automotive, and industrial machines are about the only examples I can think of (I’m sure there are others). I would specifically exclude medical devices – there are generally mechanisms in place to replace such machines every few years for reliability / sterility reasons.

      1. I have a home control system that I purchased in 2002 that was still in operation up until this year. Sadly, the company moved on to other product lines, but it ran for 15 years controlling my house.
        I’m hoping that my new home control system lasts at least as long.

  3. Does the pump do any sort of self-check when powered on? Actuate the motor, that sort of thing? If so, you might want to hook it up to an external power supply on a timer, that powers it up for a few minutes every week or so. Kind of like how long-term storage facilities for cars have people to take the cars around the block every once in a while.

    I’m just worried about lubricant settling, or the gear train getting sticky. That’s sometimes a problem on old cassette players, which probably have similar gearing.

    1. Some devices have calibration information stored in battery backed RAM. A coin cell on the PCB would be a good clue to this. If the main battery fails and the coin cell fails, any calibration information will be gone and the device won’t function. The presence of a coin cell might only be to maintain an on-board clock, but there is not an easy way that I know of to tell whether there is calibration information.
      I have an oscilloscope that turns into a brick every 8 or 10 years from this problem. the scope is recoverable by storing (on a floppy disk) the calibration data before the battery has failed, and restoring once the battery has been replaced. I doubt that this option exists on a small medical device.

      1. My guess is a supercap rather than a coin cell, because I know the RTC dies after only a few days. I just powered it up again less than 24 hours after taking the battery out — it was only in for 30 minutes or so — and the RTC was still working. I’d think a coin cell would last longer than a week, but I could be wrong.

        Here’s a look inside the Animas pump:
        Pump
        Not much to see — battery compartment below, pump drive and cartridge well on top. I can’t see much on the board to tell me how the RTC is maintained.

        1. It sounds like a super cap to me also. Depends on the coin cell and the RTC, but I would be surprised if it wouldn’t run months to a year or so on a coin cell. I did the math on super caps for powering a clock/calendar chip and they are pretty disappointing. A few days is it.

        1. I recently ordered and am about to receive new 32 pin DIN sockets for the EPROM and NVRAM chips in my TDS-520 that I am trying to restore. I picked up a desoldering iron that uses a sucker also and will try the bellows idea with.

          Figured is a good exercise to backup or see what is there with the GQ 4×4 reader/writer and then I’ll see what I can do with the NI GPIB PCi card afterwards as I think the GPIB route will provide me more access into the firmware.

    2. “Does the pump do any sort of self-check when powered on? ”

      Sort of — it just starts running the current basal program. Insulin pumps are designed to slowly drip insulin into the infusion site to simulate the baseline activity of the pancreas. So the pump moves the plunger very slightly every three minutes. To give you an idea of the scale, the full throw of the pump can deliver about 200 units of insulin, and her basal settings are something like 0.5 u/hr. So each push is 0.025 units, or 1/8000-th of the full throw of the pump. Given that the cartridge length is only about 25 mm, that means the drive train of the pump has to be able to advance the cartridge by 0.003 mm. Pretty amazing engineering.

      “If so, you might want to hook it up to an external power supply on a timer, that powers it up for a few minutes every week or so.”

      Funny you should mention that. They tend to give away meters because they know they’re going to make a ton of money on the test strips, so we have a fleet of glucose meters that I did exactly that for. I had a simple timer that kicked on for an hour or so a week, and all the chargers for the meters were plugged into that. Worked like a charm.

      The pump would be harder to do because of the removable battery. I’d have to 3D-print something to go inside the battery compartment and add contacts to provide power. Once the pump powers up, I’d need to physically push the keys in the right order to run the pump priming program to run the plunger in and out. Sounds like I’d need to pull out all the tricks — servos, 3D-printing, Arduino, and maybe even machine vision to monitor the OLED display.

      Welp, there’s the winter project – life support system for an insulin pump. Thanks!

      1. Most medical devices such as this are designed to perform an POST, that will do things such as test sensors for faults, verify the integrity of the EEPROM via the checksum, and if it’s similar to other pumps we work on will ‘home’ the mechanism to verify the sensors as well as make sure it’s at the start point.

        The bigger concern that I would have on an older device would be the accuracy of the delivery of the medication/Insulin. If the device has been in use for a long time, the question would be has the mechanism worn enough to cause an error in the actual amount of medication delivered, versus what it should be delivering. Here at work we perform an annual inspection of our IV pumps (or more often if the manufacturer requires it) and verify operation and accuracy of the sensors as well as medication delivery.

        If I was going to keep it as an backup unit, I would try and have it checked by the manufacturer for performance accuracy, then place it into storage. It should be OK to store for extended periods without an battery (aside from your noted clock issue) without having to turn it on every month or so. We have a number of devices that get pulled out once an year only for the maintenance checks, and aside from the clock needing to be reset I’ve never found an issue with the stored units.

        1. Excellent observation. I totally forgot about mentioning calibration “as left” data from when stored and taken out of service and performing the calibration and/or performance verification (PV) for “as found” data once taken out for service.

          I’d have a specification or calibration sheet attached with a procedure to instruct how to perform. This may be something you can get from the manufacturer or at least create from the specifications of the device. You may have to figure out what the NIST, secondary traceable or custom meets and exceed whatever standards that are being used.

  4. I keep wondering about oxidation of the solder joints. A little Argon or Nitrogen in a sealed bag?
    I think solder whiskers only form on powered devices.
    LCDs you need to worry about UV damage, black bag/box?

    1. I wouldn’t worry about whiskers. That’s pretty much a lead-free solder thing. That is exactly why medical equipment much like NASA gear does not use lead free solder. Just don’t try to eat the circuit board and you will be ok.

    2. I was wondering if there are ways to clean the laquer off and take older copper PCB trace boards and electroplate a layer of gold on them to beef up the board and make less likely to corrode.

      Sounds way overboard… though was something I was thinking about recently after noticing how newer boards are cheaper copper and some older boards are gold that is heavier duty.

      I was also wondering if there are ways to spray a layer of polyurethane, epoxy or silicone over the boards with components in say maybe those that need a heat sink or thermal exchange not being coated. This idea came about from submerging motherboards into cooling distilled water baths to prevent corrosion. May not be a bad idea like metal components that are coated in grease or placed in drums of oil for longer storage.

        1. That’s why I only thought gold. Silver will corrode for sure… though gold plating I don’t think will cause issues unless there is something in the copper that will or maybe copper exposed?

          Maybe I assume the old timers didn’t do this and use gold PCB’s only. Is that correct? I’ve read the Soviets were into more heavier duty gold plated and materials and gold also thicker though most was scrapped during the USSR collapse.

          I still think with plating copper with gold there wouldn’t be corrosion issues if the plating was complete and no copper exposed or impurities in the materials used to plate. There are case studies of issues where like maybe tin was an impurity and caused failures sooner. Pure gold shouldn’t.

        2. I read up a little and found an interesting modern overview. I didn’t realize there were solder issues with the hard gold systems. There are definitely a few variables to consider when plating to be successful

          http://www.epectec.com/articles/pcb-surface-finish-advantages-and-disadvantages.html

          Is that why there is less soldering in mil spec systems and more connectors and sockets?

          Though looks like there is solder used on the gold PCB’s I have even though there are more socket connectors.

    1. I’m pretty sure the cruise missiles are periodically powered up and verified to be fully functional. You would verify that all the vehicles sensors and actuators were functioning, and possibly replace the booster if corrosion or damage was detected. More likely, you’d swap out the entire missile for depot service if anything was amiss.

  5. “What can you do to make sure the device will operate again a few years down the road? Are there steps one can take beyond the typical “keep it in a cool, dry place” advice? In short, how do you preserve electronic devices?”

    Get or build a decent in-circuit ESR meter – then keep replacing all the crappy Chinese electrolytic capacitors that FAIL.

  6. Fire it up every now and then, keep in sealed bag with dessicant packs, stable temp is ideal, but hard to do. You shouldn’t have to worry about tin whiskers because most medical devices are allowed to use lead based solder.
    The Omni Pod is the best system I think for pumps, you get a whole new pump mechanism every 3 days. New batteries which are LR44 and actually made in USA are in the Pod, I take them apart and scavenge those they are strong batteries! I hope that’s the system you got now, I think it’s best for kids because no tubing! Pretty cool how it auto inserts the catheter, got a strong spring that cams over and pushes the needle and tube into skin then retracts just the needle!

    1. We looked at the Omni Pod when we were first considering a pump and decided against it. I liked the form factor, but the idea that only a few pods from each batch were tested led me to believe we’d have an unacceptably high failure rate. With a pump like the Ping or the new Tandem that we got, each device is subjected to a lot of testing before it’s shipped. We felt safer with the Ping. We also liked that it had a remote control, so we could dose her in the middle of the night without waking her up. The new Tandem lacks that feature, so we have to rummage around under her sheets to find the pump to make adjustments. Not really a problem — she sleeps like the dead.

      You’re right about the injectors for the infusion sets. They’re a marvel of engineering. Probably worth a post all by themselves.

      1. The ipad may need to be dfu’d.

        !. Open itunes and update to the latest version,
        “, Poweroff the ipad
        £, Hold the home button, or Volume down on newer models
        $, Plug into itunes making sure the cable in official or atleast capable of data transfer

        If that fails then whilst the device is plugged in, hold the home(or vol. down), hold the power button until the device turns off and the apple logo appears.(This removes passcode’s but does not remove find my iphone)

        1. Newer iDevices and/or newer versions of iOS may brick your Pad, Pod or Phone if you try a reset without knowing the lock code. Then you get to take it to your nearest Apple Store with proof you didn’t steal it and they may fix it.

          I stopped in at the local pawnshop the other day to see if they had any computers etc they needed cleaned to be sold. He had an older iPad with a lock code. Crap, without knowing that it’s a 75 mile (each way!) trip to the nearest Apple Store. Hrmmmmm…. 1 2 3 4 Hello! How nice that so many people choose stupid codes. So now the shop has a reset iPad ready to sell.

  7. If the pump motor use plastic gears it tend to break over time, it can be because the grease used to lubricate the gears, or maybe not, but if I’m right clean the mechanism before store it and apply some grase before you reuse it.
    Also you will need to verify that the pump gives the correct dose that supposedly has to give so you will need to have test equipment for that.
    Store it in a vacuum sealed bag and make a logbook to store the results of past test to check degradation over time.

  8. Just don’t.
    If failure is probable, make appropriate arrangements with your current supplier E.g. next day delivery of a replacement. . Surely they must have plans in place for such an eventuality? Hell, buy a spare if it’s a likely issue (perhaps another brand).
    Why on earth would you want to risk your child’s well being with a product that is life-threatening if it fails? I just don’t get it. Your old device, unmaintained and untested has no place in long term healthcare.

    1. My understanding is that risk to their child’s well being is the whole reason for this, because it’s life-threatening if it fails. They want a backup so that if/when it fails, either in the interim or if the “regular” backup methods fail (their backordered, shipments delayed, etc), their child’s life is at least less at risk with no pump then with an old one.
      Buying a spare would work, but then don’t you have the same problems you’re arguing against with storing this pump?

      1. If one pump fails during use, other might fail due to prolonged storage. I’d rather use manual administration of insulin than risk using a device in unknown state that might provide incorrect dosage or no dosage at all because mechanism got glued together with old grease. With manual insulin injections child will stay in good health until replacement unit is provided…

        1. Certainly not on the same level as insulin pumps, but my Father-in-law had bought my (future) wife two 12 volt air compressors for her car to refill a flat tire/tyre. Two? Well, maybe he forgot he’d already bought one. But after we married, I tried to use them. Both of their cylinders had seized from non-use.

    2. Loss of an insulin pump is not immediately life threatening, but should be dealt with in hours. Fortunately, ready substitutes exist – the emergency room for the unprepared, insulin and syringes by prescription from your doctor, etc.

      It may make sense to keep the old unit around long enough to make sure the new unit works as expected, and maybe a little longer, but not much. Beyond that, medical equipment tends to be replaced long before breakdown/malfunction would normally occur.

      Storing such equipment for the long term likely degrades reliability, and definitely degrades sterility and biocompatibility (where appropriate). How do you sterilize such things to make them safe to be stored?

      I’ve been using a CPAP device for about 4 years past its 5 year replacement date. Loss of that machine isn’t immediately a problem, but would be in a week or two. I can get a replacement in days, if needed.

      1. “How do you sterilize such things to make them safe to be stored?”

        All the supplies for the pump — infusion sets and cartridges, along with the insulin — are stored as sterile disposables. The pump itself is IPX8-rated, meaning it’s completely sealed and waterproof. It could operate if the kid is wallowing in a mud puddle and still deliver clean doses.

    3. Perhaps I didn’t make it clear that this is more a convenience backup. An insulin pump is, at the end of the day, nothing more than a convenience. It makes life easier for diabetics, giving them better control of their disease and reducing the chance for long-term complications. But she could go off the pump right now and go back to daily injections of long-acting insulin and a bolus injection at each meal to cover carbs. All that needs is low-tech needles and syringes, and a supply of the right kinds of insulin, which we have. Heck, we could even stop using her glucometer, another convenience device, and use the urine test strips we stock too. Her glucose control won’t be great, but it’ll work.

      Point is, we’re looking to preserve the convenience of a pump, so that we don’t have to put her through four injections a day rather than one injection every three days like she enjoys now. We’re on the ball enough to know if the old pump isn’t doing what it’s supposed to do, so it’s not much of a worry to us.

      I will say, though, that you seem to have more faith in the supply chain than I do. Having been caught short a few times with backordered supplies and long shipping times, we tend to take a belt and suspenders and staple-your-pants-to-your-waist and then throw on an extra set of pants approach to diabetes management. Our working assumption is that there is no next-day delivery, and that single points of failure in our systems are not acceptable. The risks of using an old pump are far eclipsed by the supply chain risks, at least from our point of view.

    1. Probably more so since I joined the crew, because my kid being diabetic has become the central organizing factor of my life. I’m fascinated by the engineering of insulin pumps and the other devices we’ve used to help manage her disease. We tend to write about what we know best, and since this is all cool tech stuff, it just makes a good fit for original articles. In this case, I wanted to get the “Hackaday hive mind” thinking about an interesting specific problem that’s probably generically useful too.

  9. It’s very unlikely there’s any grease in the mechanism. Small, plastic gears tend to become much harder to drive when greased up, even with very lightweight grease.

    If it does have any grease it’s most likely a special silicone stuff with low to zero volatile organic compounds (VOC’s) that makes it essentially immune to drying out or hardening.

    “Conventional” greases are a combination of a soap, an oil, and various additives like molybdenum disulphide. The common problem with these is when the soap has VOC’s that evaporate, causing it to become stiff, then hard, and in some cases dry to a powder.

    The technology of greases, how they’re made and what they should be used on, would be a good subject for a HaD article.

  10. Some medical devices, I think also insulin pumps, even have an expiration date programmed in In this case this “planed obsolescence” is for the sake of the patients safety to avoid danger to the patient by an unreliable device. I would try to get information, if your pump has such an issue.
    Otherwise a cool and dry place, perhaps in a nitrogen atmosphere, should be enough. I would NOT use vacuum. Some regular “exercise” (testing) every 1-2 month is also very good. At least you see in advance if it fails. I probably would not bother to automate this. That would cost more hours than doing it manually for a few years.

  11. I recently bought a HP8640B OPT323 (now I kind of want the avionics model more) for a great price.

    Prior to purchasing, I did my research to find what information is online regarding failures. Of course… I found in regards to the gears there is cracking. I haven’t measured everything out yet… though was wondering about vacuum forming fiberglass on the sides of the gears and maybe even a large enough diameter to re-cut the fiberglass resin gear profile.

    At first I though carbon fiber… then realized the electronic and magnetic properties more likely will benefit from improving with fiberglass. I haven’t read this being done yet (though did find someone on youtube, “Ramkumar Ramaswamy,” who made brass gears) and was even wondering, though will be weaker, using polystyrene as the resin. I have to do a electromagnetic properties comparison with the gear material and other materials.

    Sometimes, improving existing systems will extend the lifetime regardless of storage conditions.

    Also, itemizing PM’s as well as maintenance tasks so the whole system life-cycle is better planned for future systems activities and less hidden variable issues in the long run.

  12. I have an MS-DOS IBM Thinkpad 355CS that i put into storage as it’s lid is literally falling apart. the hinges are destroyed and the plastic is cracked and brittle. the electronics are still good though. I made a full disk image of the hard drive which is only 2 gigs, i keep it in my google drive on multiple accounts, i keep a copy on my NAS and on my local machine. In regards to the laptop, i power it up a few times a year to make sure it still powers on and boots. battery isn’t an issue as that was disposed of long ago.

    1. I have a Vic-20 I bought a while back that must of spent most of it’s life in it’s original box as it was near mint but when I tried it the PSU was dead so I made a new one and it fired right up.
      Interestingly cassette tapes seem to have a better chance of survival than floppies and hard drives since they’ll usually read so long as they never got wet or too hot.

      1. A few days back I found the Zenith Mini-Sport that I was finding other components around the house (power supply, 2.5″ floppy disks, and battery) when cleaning. I think the TI-99/4a is somewhere around here unless was thrown out when I went to Tech. I did find the cassette recorder RS-232 cable for, though nothing else yet. Found an old I think is the 80386 Zenith or 286 in a heavy duty case and IBM 486 (parts). Man, the IBM and Zenith keyboards are heavy duty and well shielded. Creepy how crappy the newer shielding is.

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