Experimenting with Supercapacitors Grand Prize – Part 1: That’s Not a Spectrum Analyser!

It’s Christmas – a time to be thankful and a time for reflection. Top Members will know just what a busy and difficult year it has been for me, but nevertheless, I am extremely thankful to the judges (DAB , anniel747 ) and to the staff (srutledge , rscasny ) for awarding me the grand prize for the Experimenting with Supercapacitors Design Challenge. This pair of postings comes rather late, in part, due to some challenges in the logistics of getting the prizes and getting them to me. But just like a Christmas miracle – they have all arrived, just in time for Christmas.

Whatever Happened to my Particulate Monitor?

As a part of my entry, I built a breadboard Arduino MKR WAN 1310-based LoRaWAN particulate monitor system. It functioned well for the contest, reaching 15 days of operation in the open air, only shielded by a plastic tub and terracotta tile.

Being the lazy person that I am … the system actually remained outside all this time. I just didn’t have the time to take it down. Surprisingly, it kept ticking along (for the most part).

What started as days, turned into weeks – 16 weeks to be precise. There were a few smoky days too – the result of bushfire backburns.

Signals were mostly steady, with a few days missing here or there due to a severed MQTT connection from the logging system or because of persistent cloud which didn’t allow the solar panel to gather enough sunlight to run.

There wasn’t any clear daily trends in air quality here – overall, the air quality usually is pretty excellent.

But one can easily see the daily trend in voltages – as days get longer here as we moved into summer.

All seemed swell … but then the “probe” stopped “phoning home” (forgive the Voyager 1 reference – I really hope that one comes back to life). It would seem my slap-dash approach to prototyping, which well exceeded my expectations, had reached a mission-ending condition.

The solar panel was fine – the red wire obviously faded from the sun.

The back of the barrel jack I was using showed some signs of corrosion.

But the PCBs had seen better days. It would seem that a mixture of condensation, slanting rain from more than a handful of wet days, perhaps conductive flux residue, dust and the presence of DC had set off some electrolytic corrosion which has likely reached a critical state and was causing it not to come up.

The supercapacitors seemed mostly fine, with some apparently normal white residue (it is a known effect due to the aggressive nature of the electrolytes used).

The Arduino MKR has definitely seen better days. Right off the breadboard, it looks quite corroded. I gave it a good scrub under the sink with a toothbrush and tried even a tiny bit of soap. Its appearance improved marginally.

But the biggest surprise to me was that, after cleaning, the board actually came up again and could be reprogrammed on the PC. It isn’t quite dead yet, but perhaps maybe some peripherals won’t function quite the way they used to – that charge controller and JST port may well be in some trouble.

So, unfortunately, this was possibly a partial sacrifice in the name of the contest. I should have really gone out and rescued it earlier … but perhaps, this is a good advertisement for the Experimenting with Extreme Environments Design Challenge, coming soon (which I probably won’t be around for).

Alas, I am still super impressed with how long it lasted. I’ve had breadboards fail going bench to bench – this one sat outside in rain, hail and scorching 40°C summer heat and didn’t skip a beat until the corrosion got bad enough. Perhaps my disdain for breadboards causing flaky circuits is something I should reconsider …

That’s Not a Spectrum Analyser!

With that out of the way, onto the prizes. The grand prize for this challenge was supposed to be a Multicomp Pro MP700852 Spectrum Analyzer and a Multicomp Pro MP710259 US DC Electronic Load. Just one problem – they were facing a long lead time on the spectrum analyser.

Thankfully, Sean contacted me to let me know and was willing to accommodate a swap to something else. After pondering for a bit, I decided to go with a new laptop – one to replace the Lenovo ThinkPad Edge E431 (which I originally obtained from the Tektronix RSA306 RoadTest and had copiously upgraded) that had failed after eight years of strenuous use.

My request? A Lenovo Legion Slim 5 Gen 8 (14”) AMD (14APH8) with the upgrade to 32GB of soldered DDR5 RAM and an RTX4060. This laptop would be smaller than the Lenovo Legion 5 that I previously won in Experimenting with Thermal Switches (a 17”er that I have yet to find a backpack that would fit), so it could finally be a laptop that leaves the desk. But it would also be a powerhouse of a computer, representing the best performance in the house and a bevy of firsts – first AMD 7000-series, first (modern, post ATi) AMD graphics, first Nvidia RTX4xxx-series, first OLED-display, first DDR5 and first PCIe 4.0 in the house. Despite being just under 2kg, it would also be the fastest and likely most power efficient computer in my collection. For comparison, my everyday desktop is still my AMD Ryzen 7 1700 on an Asus X370 PRIME PRO motherboard with 64GB DDR4 2800Mhz, an Nvidia GTX1070ti GPU and bucketloads of storage (NVMe SSD and SATA), from around 2017 that pulls more watts than I would care to think. This is why I have offloaded most of the tasks to the 17” Lenovo Legion 5 with its Intel Core i7-11800H CPU, upgrade 64GB DDR4 3200MHz RAM and Nvidia RTX3050 GPU where I could, which now takes residence as a desktop replacement with better power efficiency, but even that is not exactly going to be a match for this! The price for the Slim, at the time of Black Friday sales, was also exceedingly reasonable.

Unboxing

On 29^th November, the unit arrived. Shipped in its original box without any overpack, it did take a few minor scuffs along the way.

Packaged well, it had no issue surviving the trip at all.

There’s not much to a new laptop, to be honest. Aside from the unit, the mandatory paperwork, a power cable and a power adapter are all that is included. Being ordered from the US, I substituted a local clover-leaf cable in place of the included one.

A common downside is the size and weight of the power adapter – this is a chunky 170W power supply. But that is what is necessary to power such a beast of a machine. While it can also operate off 140W USB-C PD on the designated USB-C port, I’d say it’s worth the sacrifice to use the larger adapter for better performance and reliability.

The body of the unit is surprisingly light, thin, but also feels of good quality. Top and bottom covers feel like a thin metal shell (magnesium?) with a central core that is grey plastic. The design is a little odd with the hinge inset from the corner – the rear “bar” area has a charging indicator and some icons to label the rear ports.

The bottom cover is simple, one-piece, and easy to take off by removing the screws at its perimeter. The thick, tall rubber feet allow it some elevation from the desk which gives better airflow. I do like the look of the design. The battery is integrated, so there is no swapping like there may be with an older ThinkPad. A Windows 11 Home license is part of the offering.

The right side of the unit has an exhaust vent, a camera switch (electronic), an SD card reader and a TRRS combination audio jack.

The left-side has two USB-C 3.2 Gen 2 (10Gbit/s) ports, one of which is USB-C PD capable for powering the laptop at up to 140W. These ports also support DisplayPort 1.4 alternate mode for external monitors. There is also a symmetrical exhaust vent.

The rear has two USB-C 3.2 Gen 2 (10Gbit/s) ports, an HDMI 2.0 port and a “slim tip” power port. The two larger primary exhaust vents are also on the rear.

A key criticism for this design is simply that there may not be enough ports – at this time, I would happily trade the USB-A port for another USB-C port or two, but also, the lack of Ethernet is a little unusual for a “gaming” laptop. Perhaps the “thin” nature makes integration of Ethernet tricky, but I’ve seen it done. Another notable omission is higher-speed USB 4.0 or Thunderbolt ports, but perhaps this is because it’s not a “native” part of the AMD platform offering and because of power budgets.

With the lid open, we can see the 14.5” 2560 x 1600 120Hz OLED display and the thin top cover which feels almost a bit too thin. I guess that’s the kind of space saving that can be made from using an OLED display. The glossy surface of the panel does make this somewhat less comfortable to use in glary environments. The power button is central with a ring light, hiding a fingerprint sensor for use with Windows Hello. The keyboard seems a standard affair and has backlight illumination, while the trackpad is a little larger than most as well.

As one can tell from the labels, this is powered by an AMD-platform offering the Ryzen 7 7840HS CPU with its integrated Radeon 780M GPU. It also has an upgraded discrete Nvidia RTX4060 8GB for heavier graphical tasks, operating in an “Optimus” hybrid configuration. I opted for the 32GB DDR5 upgrade, because it is soldered in this model and cannot be upgraded later.

Setting the laptop up was no trouble at all. It was not long before I was greeted by the brilliantly contrasty OLED screen. Thankfully, if one wants something that’s a bit more normal, they can control the colour profiles through the X-Rite Colour Assistant applet (e.g. sRGB).

Overall Opinion

As shipped, the computer is very fast. It’s amazing to think one can have so much performance in a portable device. Despite being fast, it can also run for a decent amount on battery – I was seeing anywhere from 3-4 hours in my moderately heavy use. The weight and build quality are fine, while the fan noise is tolerable and not as annoyingly whiny as some other laptops.

Heat is exhausted mainly out of the rear but also out of the sides, which can be a slight annoyance to some. I found the keyboard to be very average with quite limited travel, which is no surprise. The OLED display had a good range of brightness and was a highlight in terms of colour gamut, however, the default profile can make things seem way too contrasty and high-gamma, with the vari-bright feature in AMD Catalyst enabled by default causing additional darkening of certain areas for battery saving.

One annoyance is the webcam which is only a very average quality 720p webcam. I found images to be grainy and somewhat poor in challenging lighting conditions. Another is the OLED display’s glossy finish which both attracts dust and fingerprints, but also makes for an excellent mirror in glary conditions. The lack of image scaling at non-native resolutions when drivers are not loaded (e.g. in certain Linux/bootable distributions) makes reading console output challenging due to the high-resolution screen. Of course, the lack of an Ethernet port, as mentioned before, is another key downside. Some people seem to dislike the MediaTek Filogic 330-based Wi-Fi card in this unit that identifies as an AMD RZ616 Wi-Fi 6E device, but I’ve had no issues with it at all, at least in Windows. Even the onboard speakers sounded somewhat acceptable - it wasn't tinny, but slightly boomy and resonant, which is preferable.

Perhaps my biggest issue has to do with Modern Standby in Windows and the tendency for this laptop to sleep even when I have disabled all the hibernate and sleep actions. If the screen times out, the system goes to sleep with a pulsating LED, spins down the fans, locks down into a low performance state and while it does continue to process for a short time, eventually, drops network connections too. I tried everything including registry edits, various powercfg commands and never really got it to a satisfactory state. It doesn’t seem possible for the screen to sleep without the whole device going into modern standby which seems to be a big bug. It’s something many have fought and lost, sadly. Instead, I may have broken a few things in my tinkering.

Of note is the following – the platform only supports Modern Standby. It has no support for S1. If one disables Modern Standby, one could enable Hibernate for S3, but then I’m finding BSODs on restoring from hibernate on a 50/50 chance likely due to a driver that isn’t happy (driver power state). I’ve resorted to disabling sleep on closing the lid, disabling sleep, disabling screen idle timeout, disabling fast startup and disabling hibernation and the system will run when connected to AC indefinitely, as long as the screen does not sleep. To preserve OLED lifetime, one can close the lid in this case to shut down the screen, which will still keep the system running, but will not render the display which also means remote access is not possible (perhaps without an HDMI dummy plug). On battery, I have decided to let it sleep, because battery life is perhaps more important. But it isn’t an ideal situation.

Finally, it also seems that stability is potentially an issue with the Nvidia Optimus system. While running CPU stability tests, I had frequent BSODs due to Nvidia’s drivers. Using the Lenovo Vantage app to lock the unit into either dGPU or iGPU mode stopped this issue – it seems that high CPU load can cause the hybrid system to falter in some way, making it a less-than-perfect scenario.

Upgrade

Of course, while the included Samsung PCIe 4.0 TLC SSD was plenty fast, I decided to swap it out for a more capacious Crucial P5 Plus 2TB that I had on hand, while whacking in a Western Digital Black SN770 2TB into the secondary slot to make this a real travel machine.

Here’s a look at the insides – upgrades are pretty easy, but there aren’t many that can be made.

It is nice to see that there are a few token thermal pads to help the SSDs dissipate some heat into the rear casing. I don’t think they are quite as effective as they can be, merely because they are quite thick which usually means quite a bit of thermal resistance, but also because they don’t cover the full-face of the M.2 SSD itself, at best, covering just the controller.

Data migration and upgrades were successful, however, it would seem that something is still not entirely happy, so sleep and hibernation is still broken as before.

Conclusion

Thanks to element14, its staff and its members for bestowing me this wonderful prize. I never would have thought that one dead laptop would lead to its replacement in such a timely fashion. It is crazy to think about just how much power such a portable unit has – I wouldn’t have ever splurged on myself in such a way, but having one in my hands has really made me more productive than before. The downside is that the new technology (i.e. shiny OLED displays) and new ideas (i.e. Modern Sleep) don’t always work the way they should and can be a step backward in some cases. Nevertheless, as an engineer, one will persist and work around the issues to make the most of it. Would I recommend this unit? It’s hard to say – on form factor, performance, build quality and price, likely yes, but with the full understanding of the modern sleep caveats that may drive you nuts (and potentially breaking hibernation and fast startup in the way that I have).

As for the second-half of my grand prize ... you'll find more about it in this blog:  Experimenting with Supercapacitors Grand Prize – Part 2: Multicomp Pro MP710259 Electronic Load (with Fun Workarounds!)