09 January, 2020

FabricFuse Fabric Adhesive

Ugh this is bad. It's got no adhesion. It looks and handles just like Plaid fabric paint.

01 July, 2019

Some Instruction Manuals

Intelligent Tracker Mini GPS Positioning USB Wire Fast Charging Data Cable 1M
S8 data line locator manual

No hole charger camera specification
Mini Pinhole Camera 1080P HD DVR USB Wall Charger Hidden Camera Recorder Motion Detection
2-in-1 1080p Mini Wifi Hidden Spy Camera Dual USB Wall Charger IP Live Cam

30 November, 2018

Continuous Video Stream Processing Integration

With the abundance of cheap processing power today (especially on phones), I'm wondering what information we can build from the continuous video stream of a camera - basically what the visual processing part of the brain of all sighted living things does. Even flying insects have to build a map of their surroundings, quickly, accurately, and without much resources. And a lot of this stuff that our brains do is behind the scenes to us, we only get the final picture, but not the raw stream or how it was processed. It seems obvious to me that visual cortexes don't process individual snapshots, they look at the continuous "video stream" and use context to determine size, distance, true colour etc.

Don't believe me? Look far away through a mesh like a screen door or lace. Keep your head still. Now move your head around. Notice how the "picture" is much clearer? Your mind is using the different perspectives to fill in the blocked areas.

I mean, we're already doing this for panoramic photos - taking each new frame, determining the overlap and adding the new region to the compilation.

What's the point? Well, we can do things like building a 3D model just from a video feed, when it usually needs a laser grid. Kind of like a CAT scan, come to think of it. Other things like determining an object's true colour, especially for shiny or iridescent surfaces. Or compensating for damaged optics like scratched lenses. Actually CCD dust removal in software sort of does this.

iOS 12's new Augmented Reality measurement tool is a good example. I believe it uses the gyro and accelerometers, and the camera. You let it look around to calibrate, then it can measure lines (e.g. furniture and room sizes) from a distance. Like your brain, it can compensate for further objects appearing smaller.

The next step I'm thinking of is what hardware can improve this. Or even better, which additional sensors can improve the quality of what we can process, at the least cost. Things like (roughly increasing cost/complexity):
  • Using the focus distance from an autofocus system to get rough distance data
  • Motion data. Our visual and balance systems are tightly connected, hence motion sickness and vertigo.
  • Dual cameras for parallax - just like nature!
  • Laser grid for accurate distance measurements - like the Kinect and Apple's Face ID
  • Bracketing (so faster image capture - faster processing, shorter shutter times) in focus or exposure (HDR) or white balance - process multiple elements in one picture
  • Now, the most complicated upgrade will be to build an OBJECT DATABASE. Think about it - when you look at something new, you try and identify familiar elements and match it to things you already know. Size-shape-colour-surface details-movement. 

They're already working on things like machine vision and captchas and recognising cats, but I think the key difference of this is CONTINUOUS VIDEO. It's what nature relies on and can give so much more information.

17 November, 2018

iPhone 7 Plus Battery Replacement

Replaced my 7+ battery and Taptic engine under AppleCare warranty at the Apple Store. Took 3.5 hours. MAKE AN APPOINTMENT. Battery was at 83% life, 500-600 cycles (can't remember exactly). 23 months old. Warranty for replaced parts extended to 90 days from date of service. Would've cost $35 + 82.

AppleCare is getting more and more expensive and I wasn't going to get it for my current iPhone at first, but the fast and easy repair, no-questions-asked, and convenient location sold it for me. The opening of the Apple Store in a central location greatly increased its value.

05 November, 2018

Glass Screen Protectors and Planned Obsolescence

Glass screen protectors are the textbook example of planned obsolescence. When you got a plastic screen protector, how often did you have to change it? Sure, they got scratched up, but they easily last the life of the device. You'd be lucky to have a glass screen protector last a month. This was at 11 days:
And they're so much more expensive than plastic - at least 2x, up to TEN TIMES the price. So let's see: costs A LOT more, has to be changed monthly if you're lucky, it's no wonder shops have conveniently stopped selling plastic screen protectors. Wonderful business for them.

"Oh but they sacrifice themselves to protect your screen" that's what all the advertising says - utter drivel. Ask people how they broke their screen protector. Most people don't even know WHEN they broke it. It wasn't during a major fall - they break in such inconsequential, day-to-day use that they offer no protection when it's really necessary. This broke in a 50 cm fall onto concrete, something that would have caused 0 damage to a naked phone.

Previous post

28 October, 2018

Banksy's Self-Destructing Painting

On 5 October 2018, famous anonymous street artist Banksy's painting "Girl with Balloon" was auctioned for £1,042,000 by Sotheby's London, immediately after which it partially shredded itself via a contraption hidden in the frame.

Soetheby's and Banksy are claiming that the auction house didn't know this would happen, and people seem to be accepting this at face value, but it doesn't make sense to me.
  • This art piece has been in their possession for 12 YEARS. It's not like they just received it yesterday and stocked it on the shelf.
  • Ok the frame had lights that needed power - no concerns about batteries lasting that long here. It's also easy to conceal the paper exit.
  • "Yep, we'll just take this huge bulky frame and hang it in a small room next to extremely wealthy people without any scrutiny whatsoever, not even, you know, A BASIC X-RAY that will reveal the BLADES, MOTOR and WIRING hidden inside"
  • Awfully fortunate publicity for Sotheby's, who now has an article on it on their website https://www.sothebys.com/en/articles/latest-banksy-artwork-love-is-in-the-bin-created-live-at-auction

09 September, 2018

USB Meters Revisited

My PortPilot (Pro) is sadly outdated and no longer seems to be in development. The main problem is lack of support for USB 3 and Quick Charge standards, particularly higher voltages up to 30 V.

Happily, the prices for USB current meters have come way down, and there are so much more choices and functions. Some examples:
This is about the simplest you can get. Only measures voltage and current, and only displays one of these at a time.

The ZY1276, by YZX Studio. Although it's at least a year old (came out not later than August 2017), it remains the most comprehensive meter to date. Even so, it's not even 60% the price of the PortPilot Pro when it came out! Look for videos of this meter, they cover it better than I can. There are newer models that claim to do all this can and more (ZY1275), but I won't believe it until I see a review.

Some models intermediate in price and functions
There are a few main brands now:
  • YZX Studio, maker of the ZY1276 above, claims to be the original. Supposed to sell from 2 eBay stores but they were out of stock when I wrote this. Still available elsewhere.
  • Ruideng (RD) official store on AliExpress - makes a few big models like YZX, but cheaper and with less functions. Also makes 6 similar small models in blue plastic like the one shown above, confusingly. One with a colour screen (AT34).
  • Power-Z - this one is unique in that it has a much faster update frequency, almost like a mini oscilloscope they claim. Unfortunately no manual exists so no one has unlocked its true potential.
  • Hidance on AliExpress sells many models but they look like rebrands. In particular, their most advanced color big display model looks like RD's.

Ok now let's talk about their features:
Voltage and current measurement
Obviously they all can do this, but their precision and accuracy can vary widely. The ZY1276 above you can see goes to a whopping 0.00001V and 0.00001A! Their maximum limit varies as well. I think for Quick Charge the max is 12 V and for Power Delivery it's 30 V.

The measurements are affected by temperature or drift or something. The PortPilot Pro displays 2 mA even at no load. Even simple meters now can zero their readings, or you can manually offset if you have an accurate reference.

Mainly useful for testing power banks (ugh I don't like that term but it's the most understood), so if you test them unattended until they switch off you don't lose your data. There should be a distinction between those that just keep a summary (time, total energy/Ah), which only needs a few bytes of memory, and those that keep the individual readings at every interval.

microUSB or Bluetooth? To computer or Android?

Charging Protocol Identification/D+D- reading
One of my main reasons for getting the PortPilot Pro was to identify the charging protocol of different chargers and why some chargers charged faster (it's not due to their current capacity). There are lots of new protocols, in particular Quick Charge 2 and 3, which the PortPilot Pro obviously can't identify. The older protocols seem to have settled on DCP and the various Apple protocols (1, 2.1, 2.4A). Some meters try to identify the protocol. Some just give the raw D+ and D- voltages, which you can use to look up the protocol. The advantage of D+ and D- voltages is it'll be compatible with future protocols and updates, unlike for example the PortPilot Pro which can't identify new protocols without a firmware upgrade. I think it's also simpler to program displaying D+ and D- than the protocol names and ranges.
Meters with this: PortPilot Pro (only a few protocols, no D+D-) I think all of the big screened ones, Hidance's LCD and OLED ones (only D+D-, no protocol names):
Gwunw's BY56U and BY58U (only D+D-)
RD's AT34:
RD's other small meters don't. Specifically, USB 2.0 3 bit, USB 3.0 4 bit, USB 3.0 4 bit H, USB 3.0 protector, and USB 3.0 comprehensive all don't.
The ZY1276 goes one step further. All the previous meters just show you the single protocol that's in use now, not all the protocols the charger is capable of. This is an issue because new charging chips are actually capable of almost all the protocols, depending on what the device asks for. The ZY1276 can actually test each protocol in turn, and give you a list of what protocols your charger supports.
(I think this is the ZY1280, which can also test all the protocols)
Power-Z's can do the same thing.

Protocol Emulation/Charge Boosting/Quick Charge/Fast Charging
Remember my iHustler and Wocol Charge Booster?
Surprisingly, this simple function isn't that common. The ZY1276 doesn't do it... that well. The PortPilot Pro did, but it needed a computer to activate it. Which is a pity, since it would be so much more useful if it could change modes by itself.
Meters that have it: you have to pay attention, most meters that have it, have an automatic mode so you're not sure which protocol it's emulating. ZY1270 is the only YZX meter advertised with it, but I suspect the ZY1276 can at least do Apple 2.4A. The BY58U has it. Some of RD's small meters too (it's annoying because their AT34 only measures D+D- and the smaller ones only emulate):
Honestly, this feature is kind of hard to find and you might as well get a dedicated adapter like the iHustler. Or PortaPow. Or Pisen has a few but not on their AliExpress store so I think they're phasing it out.

Temperature measurement
Even lots of cheap meters have this, but it doesn't seem that useful to not measure the temperature of the power supply or load, so I think they're putting it in for a different reason. Probably resistance or something changes with temperature and they need to measure temperature to compensate. Since they're already measuring it, might as well display it. Note that almost all smartphones today can also measure temperature, but very very few let you access it.

I think all the meters with big screens can plot a graph of voltage or current against time, but their usefulness is limited by the slow refresh rate. All seem to be 2 Hz, even the ZY1276, except Power-Z's meters.

Cable resistance
After charger capacity and compatibility, I think cable resistance is the second most important factor affecting charging speed, and it's something the PortPilot Pro can't do, at least not without some modifications. To measure resistance, the meter needs an in-port for that type of cable. Most high-end meters have microUSB and USB-C in. Only 1 or 2 have Apple Lightning in, unfortunately. And they all call it 8-pin, because of copyright reasons. Measuring resistance is a bit fiddly. You have to plug the meter directly into a source and take a measurement, and now use the cable you want to measure to connect the meter to the source and take another measurement.
Tip: if your meter doesn't have microUSB/USB-C/Lightning input, you can use this adapter to convert these 3, and others, to normal USB-A. This lets you have almost any input on any USB meter. Simply put, you can test cables on any USB meter.
There are a few meters that let you plug both ends of a cable into the meter and it'll test the cable like that. The BY58U has an expansion card for microUSB:

USB Loads
If  you want to measure output capacity and resistance at high currents, you need a stable, adjustable load. Yes it's just a bank of resistors that converts USB power into heat, but I guess it's necessary for accurate measurements. DO NOT GET THIS ONE:
Its exposed surface hits 200C in normal use what is this, it's not a burn hazard, it's an ignition hazard!

02 September, 2018


1. Can we stop calling every single controversy -gate? It's being used for the slightest things now.

Ok there's a lot of fuss and mystery over kids' videos popping up frequently now on YouTube which have been adulterated with violence, gore and sex. This is a valid concern.

What I don't get is HOW DO WE NOT KNOW WHO'S BEHIND THESE VIDEOS?! These aren't some hack jobs by 1 person, these are fully animated videos. It would take 1 person with animation experience significant time to make - either a "talented" person spending a lot of time, or there are whole teams working on this. THERE ARE LIVE PEOPLE SHOWING THEIR FACES IN THEM. New videos are popping up all the time - almost faster than they can be removed. Yet we have no idea where this deluge is coming from, or what their purpose is? People are even suggesting they're computer generated - does this even seem possible? I'm sure AI hasn't developed to the point of being able to write and draw cartoons automatically.

And what is their purpose? People's suggestions seem rather weak. Ok let's take the 3 suggestions from Wikipedia:
  1. "financially lucrative" - as I've said, these require an investment to make and YouTube isn't famous for paying money directly. Rick Astley has only received $12 from rickrolling. As I understand, most people are earning from sponsorships by other companies, not from YT views. Also, kids aren't that great a market, I'm saying most views on such videos are by bots. In that case, why even appeal to kids and draw attention? Make videos by bots for bots, make money. HOW CAN YOUTUBE NOT KNOW WHO THESE ARE IF THEY'RE PAYING THEM MONEY?!
  2. Grooming/brainwashing - ookay, let's try to brainwash all the kids today using a method of no known efficacy, in the chance we'll come across them and they'll be susceptible to our lecherous plans. This is just like the "drug dealers give free drugs" urban legend, only it's only believable to 5 year olds. It's like the plot of an Austin Powers movie.
  3. Coded messages - let's send messages - that are so secret that we have to encode them - using the most visible and trail-leaving method possible online.

Ok, what? Seriously? Let me summarise:
  • Extremely visible and attention attracting videos, with personal identifiers. In large number.
  • Where do they come from
  • Where do they go? (what's their purpose?)
  • With so much information about them, we still don't know? Seriously?
Is this odd to anyone else? Why do I feel like a conspiracy theorist when I say IT'S NOT POSSIBLE THAT WE KNOW SO LITTLE? There's more information out there, and it's not being picked up or being hidden. It's like saying there's a motor vehicle abandoned in a major city, and nobody has any idea where it came from.

24 July, 2018

Panasonic Air Purifier Replacement Filters

Remember my Panasonic F-PJD35A?
First reviewed in 2011
And again during the haze in 2013

I'd been using the filter waay longer than recommended (2 years) because I couldn't find replacement filters for it. Panasonic has poor support for their air purifiers. Surprisingly the old filter could still reduce PM2.5 to 1, measured by my Xiaomi https://mbni.blogspot.com/2018/01/xiaomi-pm25-detector.html

Apparently it's much easier to find new filters than expected. All that seems to matter are the numbers in the model name - 35 in this case. All models using the same numbers appear to use the same filters. I bought the filter for the F-PXF35 / F-PMF35A and it fits. Size is stated as 402x217x32.

So what's the filter like?
 Yeah, the old one is a little dusty on the inside...

It's supposed to be white??

The old, original one has a thick layer between the outer mesh and the pleats. It released a lot of dust when I cut it so I didn't cut further.

25 May, 2018

I'll Do You One Better: Why Gamarue

Some weird things happened. I put my USB drive in another computer - looked normal, except there was a shortcut to Removable Disk. I thought it was from vaccinating/inoculating the drive against autorun.

Put it in my computer. Files missing. Shortcut turned out to be an actual shortcut to rundll32.exe, with a weird string behind.

Scanned with antivirus. Found Gamarue A.

To unhide files, use
attrib -h -r -s /s /d *.*
from https://www.easeus.com/file-recovery/virus-file-recovery.html. Files will be in a folder without a name (space? special space? undisplayable character?)

Ok, search for new computers on Google. Click on ad link to lenovo thinkcentre. Can't display page, says pixel.everesttech.net is unreachable. What? Where does this server come in? Did my browser get hijacked?

Firstly, everyone should check the real URL when mouseovering a link. But did you know it's easy to spoof this URL? Display one URL but actually send you to another? Google does it for ALL search results, not just ads. You only notice when a page doesn't load properly, though.

But can ads on Google also do this? Display a safe URL but actually redirect you to a malware site? Technically not... https://security.stackexchange.com/q/161071
They actually can, but only to "certain" "vetted" sites. So the only thing stopping them is Google's "vetting".

So what about everesttech.net? Is it a virus site? It looks like a common ad tracking site, like googleadservices. Look at the stackexchange discussion above. So why doesn't the link in Google ads work? Because everesttech.net is down.
It's a coincidence, this huge site that Google ads depends on is down.

  • USB drive got virus
  • Found way to unhide files hidden by virus
  • Google ad links not working
  • Thought browser was hijacked
  • Turns out a major site was down just as this was happening to me

But wait, something is weird. Google ads works normally on linux. Check my hosts file. I blocked pixel.everesttech.net!
  • everesttech.net isn't down, it just doesn't respond if you visit it directly. Suspicious.
  • everesttech.net also isn't malware, it's sort of necessary. Don't block it.

31 March, 2018

CCTV/IP Camera Storage Solutions

  • IP cameras now are cheap, but there's no good solution for storage.
  • Cheap cameras have no local storage.
  • Cheap cameras can email, but now you have to wade through thousands of emails.
  • I couldn't find any cheap FTP services
  • Even on expensive cameras, storing on microSD cards is vulnerable - it lets anyone with access to the camera destroy or even copy recordings

There are sites that offer hosting services (e.g. search ip camera hosting). They even support webcams. However, they're ridiculously expensive. CameraFTP starts at $3.50 a month, for the worst image quality, only 1 camera, and only 7 days storage.

Why can't we use free cloud storage like Google Drive and Dropbox? Problem: they don't support email or FTP uploads, even for photos. Since none of the companies support this, it's obvious it's an intentional omission, probably to prevent abuse (like website image hosting).

Well, there are websites that provide email-to-cloud services for you. And https://www.emailitin.com/ is only about $3 a month for unlimited use... Since I've started, their files counter has doubled. It works great so far. Pictures from the camera are stored in my cloud service, for as long as I want, to browse like any other photos. I can even add as many cameras as I want, or allow others to upload too.

25 March, 2018

Xiaomi Mijia 1080P Smart IP Camera SXJ01ZM

Most official webpage I could find: https://www.mi.com/mj-camera-1080p/ don't be fooled, there are lots of Mi "fan" pages. Some are inaccurate. All try to sell you stuff.
A good review: http://www.jayceooi.com/mijia-1080p-ip-camera-review/

Ugh, Xiaomi, can you come up with unique names for your cameras? There must be like 5 cameras called "Mijia". How to distinguish this camera:
  • Obviously the best is SXJ01ZM, but not many places call it this.
  • Some places also refer to it as 130°, which is pretty unique, and distinguishes it from the 360° cameras that look the same.
  • There are a couple of cameras that look like this - black circle in white oval frame. The 360° ones, more expensive, have the black part protrude out the front when viewed from the side. I think this is the only camera where the black part is removable, a feature I like (see below)

This is what it looks like. As is usual for this blog, I'm going to focus on things other blogs don't cover. Here are the features covered by every other review and reblog that I'm not going to repeat past this:
  • 1080P full HD
  • 2.4 and 5 GHz dual-band wifi
  • Bluetooth (for setup and auto sleep)
  • Night vision with IR LEDs and IR filter. You can hear the filter moving in and out.
  • It's only 20 FPS?
  • WDR (same as High Dynamic Range)
  • microSD card slot
  • 2-way audio
To me, the most interesting feature is you can take out the black part and hide it better. The white part is just a frame.
Other interesting features:
  • Well the main selling point is the price, other brands' HD cameras are twice the price
  • It runs off microUSB (power only, no data) so you can power it from a USB battery
  • I'm not sure how common a moving infrared filter is on these cameras, but I always find it interesting
  • Using Bluetooth, it can detect your Mi band or phone (which brand?) when you're nearby and stop recording


  • It does what it's meant to do very well. And coupled with the low price, this is a bargain - if it meets your requirements. Unfortunately I always seem to have unusual requirements, so it falls a little short for me.
  • By "very well", I mean image quality is good, it's relatively easy to setup and use, 130° is super wide (compared to my cheap Dlink camera; don't know if it's wide for other cameras), and I think its strongest point is it's easy to immediately see what times motion was detected.
  • My main concern, which I think applies to all users, is its heavy dependence on the Xiaomi servers. Its functionality is severely limited without them. This has 2 issues: 1. dependency - what if Xiaomi or your Internet access goes down etc. 2. security and privacy

  • It talks during setup! Fortunately, it doesn't seem to make uncontrolled noises at other times.
  • You can set it up for wifi networks while you don't have access to that network. e.g. you can set it up at home for your office network.

Offline use:

There are basically 3 recording modes: continuous, motion detection and off. Motion detection lets you set areas and sensitivities. No sound activation. Sound recording can't be turned off.
You can also put the camera to sleep, during which the only thing you can do is turn it back on. i.e. you can't review files. So stopping recording (the top picture) is a better idea. Oh since the latest app update, the Chinese "stop recording" has been properly translated to English.

XiaoMi and SJCam, can you stop calling it "watermark"? It's a time and date stamp!

  • You NEED a microSD card. Without a card, you're limited to live viewing (and maybe recording from the app)
  • With a microSD card, you can also record to a NAS.
  • Surprisingly, no email or FTP like on even the cheapest Dlink cameras

Main Issues

26 February, 2018

Mercury MaxPlug 6 USB Smart Quick Desktop Charger 10Amps

  • 5 USB ports, up to 2.4 A each, total 8 A
  • 1 Qualcomm Quick Charge 2.0 port - 5V 2.1A / 9V 1.67A / 12 V 1.25A
I was wondering who the real manufacturer/OEM of this USB charger was, since Mercury is obviously a rebranding. Searching for Mercury MaxPlug didn't find anything. Well the inside says model ASSA60-050800-15W and searching for this returns very similar products, so I think this is the real model number. Hope this helps whoever's looking for the real manufacturer.

Always searching for a better charger. Innergie is my favourite, but they refuse to update themselves and come up with anything more than 2 ports. Anker is popular and I have 2, but they don't have Quick Charge.

25 February, 2018

Splitting Thinkware Video Files

If you have the rear camera installed in your Thinkware dashcam, the 2 video data are stored together in 1 .avi file, which is a pain to view and share. Some video players can only view 1 video stream. VLC opens additional Direct3D Output windows all over the place. Thinkware's software is useless for this. Score another black mark against Thinkware since other brands' software have easy ways to split/export videos.

I've found a solution!
Using ffmpeg, the magic words are:
ffmpeg -i test.avi -map 0:0 -vcodec copy output1.avi

30 January, 2018

Sjcam M10 Action Cam

I grow increasingly frustrated with my Thinkware dashcam. At best, it takes 45 seconds to boot up. This in itself is ridiculously and unacceptably long. Sometimes it restarts and doesn't start recording for 2 minutes!

So, I got the M10 (actually M10 wifi), mainly because it had auto start stop (search for action cam auto start stop), meaning when power is applied, it turns on and starts recording, and when power is removed, it shuts down.
MAIN PROBLEM: if you leave the battery in the camera and the camera in the car, the battery will swell in a few months. This sounds too dangerous. Fortunately it "works" without the battery, except the camera doesn't get to shut down properly so the last video is corrupted. Some people don't have this problem https://dashcamtalk.com/forum/threads/sjcam-m10-as-a-dashcam.13427/page-4#post-267637
  • The M10 starts up and starts recording within 10 seconds when power is applied. This just highlights how abysmal the Thinkware is.
  • Videos are divided into a minimum of 3 minute blocks. There's less than a second gap between videos (I couldn't measure the gap on my watch). Remember, the last video is corrupted, so drives less than 3 minutes may not be recorded.
  • Speaking of corrupted, I suspect the data is there (the file is), it's just missing the "packaging" (headers). So it should be fixable. This is also a problem on Dji drones and GoPros, and there are small programs to fix them. I didn't manage to fix the M10 videos though.
  • Mine doesn't seem to have any internal power at all, if I remove the battery when the camera is off, even for a few seconds, the clock is reset.

Update: This is complicated. I'm doing more tests. It seems files are ok before the card is full.
There's a major problem since I'm using it without the battery. The clock resets, and since files are named from the date and time, all the files have the same name and the camera wasn't designed to handle this. I'm not sure if it flat out doesn't save if there's already a file with the same name, or overwrites it, but most of my files couldn't be played and I couldn't find any of when just starting the car, the sole aim of this camera. If you're looking for a dash cam, a dedicated one may be better. Not really this camera's fault, it wasn't designed to be used without the battery.
Possible solutions?
  • Set the clock / keep formatting the card - not practical.
  • Manually start/stop recording at a random time so the files don't collide.
  • Use the battery. Protect the camera from heat / avoid continuous charging to prevent battery swelling.

It's not that bad. The filename format is:
where xxx is a kind of a running serial number. It's supposed to reset when the camera is switched off, but it takes longer than that (see how the first few files have serial numbers as high as 30. The date and time of 2016_0101_000005 indicates these files were the first created when the camera started, yet the serial number is already up to 30). Files are named with the time at the START of the recording. You can see most of the hhmmss in the files below are 000004 or 000005, showing that the clock starts 4-5 seconds before recording starts. Thanks to the serial number, there don't seem to be any conflicts.

The files without thumbnails are the corrupted ones because the camera wasn't shutdown properly.

So, the problems are:
  1. Last file before shutdown is corrupted - you can avoid this simply by stopping recording before turning off the engine. It only takes 2 button presses and no waiting.
  2. All the dates are the same so it's hard to tell which file is today's, yesterday's etc. 
  3. When the card is full, overwriting older files doesn't work so well. Because the camera can't tell which files are really older when they all start with 2016_0101. In particular, it rewrites the 0 and 3 minute files first. Other files seem ok:
This is troublesome for me because the 0 and 3 minute files are exactly the files I want, those that cover the startup of the Thinkware camera.

It seems to work ok until the card gets full and has to overwrite files. So if I format the card before it gets full, it can cover my needs, except the last file is corrupted.

Lens Cover:
The camera is nice, but it's not very popular and the bubble-shaped lens protrudes, so it's difficult to find lens caps/covers to protect the lens. You can use the waterproof casing. I found this one that sort of works:
"Minismile UV Filter Lens and Lens Cover Kit for Xiaomi YI II / 4K Action Sport Camera  -  BLACK 250035301"
The clear one is like a UV filter - you can use the camera with it on. It's a bit big. You can wrap some tape on the lens or filter to tighten it up. I use PTFE thread seal tape (plumbing "teflon" tape), which doesn't have any glue. There's some vignetting in the right corners, only visible in videos, not pictures. I think you can get rid of it if you position it just right.
The opaque cover fits and doesn't drop, but it touches the lens.


06 January, 2018

Xiaomi PM2.5 Detector


Remember my air purifier posts?

My search for quantifiable air quality led me to this PM2.5 meter. Random specs:
  • OLED screen (black and white, dot matrix)
  • 2 hour battery life
  • Has wifi, but not very useful
  • Has clock mode
  • There's a tiny fan in the back
Yea... what else do you want to know? This blog probably knows more than me about air purifiers http://www.myhealthbeijing.com/china-public-health/my-quest-for-the-ideal-air-purifier-is-over-xiaomi/
Again, air and water. Everybody needs these. All the time. Yet there is very little, you could say practically none, measurement and control over their purity, done by individuals. People only react to problems when they arise. No prevention and monitoring.
Singaporeans baffled by strong, mystery smell 26 Sep 2017
"A strong odour that smelt like burning chemicals or petrol, along with smoke that stung the eyes, fanned anxiety among many yesterday as it spread from north-eastern parts to the western areas of Singapore."
"The SCDF said at 9.55pm that its monitoring teams have not detected the presence of toxic industrial chemicals in the air.
In an update at 10.34pm, the NEA said it had received feed-back from the public about a gas smell in Sengkang and Punggol around 5pm.
"NEA officers were deployed to those areas immediately to investigate the smell feedback," it said, adding that air quality levels during the period were found to be well within safety limits."
Does anyone see the problem with this? We can only test for specific things, things we expect. Faced with an unknown chemical, we're helpless.

Anyway, sorry, this product won't help with this. It only measures particles. It doesn't detect organic compounds like alcohols. There are some detectors that detect formaldehyde and CO, but, again, these are very specific and won't warn you about other chemicals. Interestingly, the air quality sensors in air purifiers like the Panasonic one I have react to solvents like alcohol, as well as particles. If only there were a way to get a number out of them...

So here are some observations about the Xiaomi one:
  • Has wifi, which doesn't do much. Can connect to the Xiaomi server and let you see remotely, and occasionally log data. You can use it 100% standalone without wifi, then it's a simple display of PM2.5. Wifi can't be turned off though.
  • Seems to be meant for the China market for now. You have to set your locale to China in the Xiaomi app. At least you can switch the language to English.
  • DOES NOT LOG. Not their fault, I don't know why I expected it to. If you're connected to wifi, it seems to save readings every 30 minutes in the server. Doesn't seem to have memory of its own.
  • There's a clock mode, which isn't very useful. Time in 24hr format, date and day in Chinese. Can't be changed. Main problem is it reverts to clock display, which doesn't show PM2.5, you know, its primary purpose. No wait, main problem is IT DOESN'T SEEM TO EVEN MEASURE PM2.5 IN CLOCK MODE. By this I mean when I switch from time display to PM2.5, it acts like it's booting up and you need to wait to get a reading. At least clock mode can be turned off.
  • There's also a night mode, which doesn't do anything that I can see.
  • PM2.5 doesn't seem correlated to visible dust. I mean I still get low PM2.5 readings in dusty environments. I guess dust is bigger.
  • Shuts off in 30 minutes when running on battery.

So far, I think design is good, quality is ok, but it can be so much better with a firmware update. Choose clock faces? Display PM2.5 and time... together? Ok I'm assuming it doesn't even have a few kB of data for logging, which is poor design, but... log directly to the phone? Wifi hosting for portable use?

28 September, 2017

Reminiscing 2

Reminiscing, 18 November 2011

  1. Wow, this blog is 8 years old
  2. The wave of nostalgia continues, greatly boosted by SG50. Now there are all kinds of products inspired by history, not just the 90s. I'm perfectly ok with reminiscing, but not with pretending like you're part of a secret club that turned out ok despite the trauma of growing up without the Internet.


I was thinking about this mini-game in a Sega Genesis game, where there are 5 vertical, straight, parallel, narrow islands and you pick 1. You walk up the island, and there are bridges randomly connecting adjacent islands. If you come to a bridge, you must cross it. It's a random chance way of picking a bonus prize, like drawing lots. Read the Wikipedia article, it's got a better description.

Anyway the Genesis game is very old and I thought it was pretty small and unknown, but I still found it. It's called Magical Hat no Buttobi Tabo! Daiboken. Aah, this brings back memories.

22 September, 2017

Things In 2017, Part 2

  • Lee Hsien Loong has public disagreement with siblings over Lee Kwan Yew's Oxley Road house 

  • SMRT delays on 17 Aug evening and 18 Aug morning 
  • US protests by nazis? racist somethings? counter protests? https://en.wikipedia.org/wiki/Unite_the_Right_rally and removal of Civil War statues 
  • Total solar eclipse over a large region of the US 
  • Hurricane Harvey, biggest hurricane in the US in 12 years, mainly in Texas
  • North Korea launches missiles over Japan on 29 August and 15 September

US Ship Collisions 


  • Gunman kills 60 and injures 500 in Las Vegas
  • Flooding in SMRT tunnel between Bishan and Braddell. Lapses in maintenance found.
  • Hollywood stars accused of sexual abuse. Particularly Harvey Weinstein and Kevin Spacey 

  • SMRT trains collide at Joo Koon

  • Freelance taxi companies/apps like Uber take off around the world
  • Bike sharing companies (that let you pick up their bikes from the street and leave them anywhere afterwards) explode in popularity in Singapore and Australia despite not having proven their business model. Leading to bikes stolen, vandalised, abandoned, put up in trees, and thrown in rivers.

Fractions Of Petroleum

I see that a lot of petroleum products are just mixtures based solely on molecular weight, nothing else. It's weird, right, petroleum is a multi-billion dollar industry and I can't find such a complete list of petroleum products, by increasing molecular weight, that contains terms used in different countries, that I had to make my own:
  1. Liquefied petroleum gas 
  2. Naphtha  (5-12 carbon atoms)
  3. Petrol/gasoline (5-8 carbon atoms)
  4. White spirit/mineral spirits/mineral turpentine/petroleum spirits (7-12 carbon atoms)
  5. Kerosene/paraffin/lamp oil (6-16 carbon atoms)
  6. Diesel (8-21 carbon atoms)
  7. Mineral oil/paraffin oil/liquid paraffin
  8. Petroleum jelly/Vaseline
  9. Paraffin wax (20-40 carbon atoms)
  10. Fuel oil
  11. Asphalt/bitumen/tar 

https://chem.libretexts.org/?title=LibreTexts/Sonoma_State_University/SSU_Chem_335A/Material_for_Exam_2/Unit_3:_Organic_Compounds:_Alkanes_%26_Their_Stereochemistry/3.8_Gasoline:_A_Deeper_Look has a good general classification:
  • 1-4 carbon atoms - gases
  • 5-10 - naphthas 
  • 10-16 - kerosenes
  • 16-60 - gas oils
  • >60 - lubricants
  • >70 - fuel oil
  • >80 - asphalt