29 June, 2020

iOS Photos' Privacy

iOS urgently needs to offer more control over apps' access to photos. Specifically, between always access and one-off. It needs to take control over the photo selection process and only give the app access to the selected photos - just like how it handles in app purchases. The app doesn't know anything about your account.

When you upload a file to a website, does that website have access to all the files on the device? No. The browser only hands over the selected file. iOS needs to do this too because most apps simply don't need access to all your photos. I've seen shopping apps with access to photos use your photos to recommend items. They're going through your photos! Social media apps are definitely doing the same. With memory capacities increasing and people storing all their photos on the device, this is a huge privacy flaw.

There is no need for most apps to see all your photos, only those you choose to upload. Maybe only backup apps need access to all. And it's simple. Let the OS handle the selection dialog. Or designate shared folders.

25 June, 2020

Smartphone Gimbals Comparison

I was looking for this when choosing a gimbal, but nobody's done it. Not even the manufacturers. All their gimbals are piled on one page, with no indication which is older, which replaces which, what each is designed for, only vague things like "for vlogging" "for travel". Except maybe DJI, but they only have 1 current model.

So I did what the manufacturers and reviewers and bloggers should have done, and copied all the important specifications on one spreadsheet. I think the first thing to look at is the release date, and exclude everything before 2018.
You should be able to click the image and see the original size, and here's the original spreadsheet that you can download and filter. And I might update:

01 June, 2020

Smartphone Gimbals - Features To Consider

Gimbals are getting easier to buy, cheaper, and more companies are making them, but they're still less popular than drones. Nobody I know has used a gimbal so I couldn't get any advice. I went ahead and got my own, so here are the features you might want to look for when buying your own:
  • Modes, in order of decreasing freedom of movement / increasing restriction:
(most freedom of movement)
Point Of View - allows movement in all 3 axes (tilt, pan and roll). Basically just smooths your hand movement.
Following - smooths tilt and pan movements only. Doesn't allow rolling, i.e. keeps horizon horizontal.
Pan Following - only allows pan movement.
Locked - keeps camera pointed in the same direction, to the best of the gimbal's ability. If you move the gimbal a lot in one direction, the camera keeps pointing parallel to its original direction. i.e. the camera behaves like it's on a slider.
(most restricted) Note: the instructions are not strictly accurate. e.g. they say in Locked mode, all axes motors are locked. Obviously this isn't true, or the gimbal would behave as a selfie stick. What they mean is the motors compensate for and negate movements in any axis.
  • Vortex mode, where the camera rotates about the lens/roll axis. In my opinion, this effect isn't as nice as the professionally done one, because the rotation axis isn't aligned with the lens, so there's another form of movement in the video. Vortex mode requires:
  • Pan axis rotation. My gimbal says it's 360°, but it's really infinite rotation, which is much more impressive, because it has to have a slip ring system in there. Especially since the pan axis is the first motor, and all the connections to the other motors have to pass through the slip ring.
  • Independent functions. I'm talking about what the gimbal can do standalone, without any connection or app. Because this way you can use it with any other app, or even other devices. Like making video calls. My gimbal can use all the above modes standalone. Actually the app doesn't seem to add that much functionality.
  • Selfie mode - rotates the phone 180° to face you. Useful if you want to use the back camera for selfies.
  • 90° mode - smartphone gimbals are usually designed to shoot horizontal video when holding the gimbal vertically, i.e. the phone is perpendicular to the gimbal, like a T. If you shoot a lot of vertical videos or streams, you might one that can quickly rotate or at least hold the phone vertically, parallel to the handle. Mine doesn't really do this, but it has a pseudo-90° mode where you can hold the handle horizontally and it stabilises the phone vertically.
  • Tracking - this is probably the most important/useful function of gimbals, and it requires the app. You mark an object in the video and the gimbal tries to keep the camera pointed at it as the object/camera move. Obviously strongly dependent on how well it separates the object from the background, especially as the perspective of the object changes. You might put the gimbal on a table and have it track you as you walk around. Sort of like a security camera. You might track a model/building as you circle around it.
  • Movement range of the gimbal. An important feature to look out for. As I said, mine can pan infinitely, but the movement range in other axes isn't so good. Actually the specifications are fine, but due to the small gimbal/large phone, the phone keeps obstructing the gimbal from moving freely. Another limitation is that its movement range allows it to hold the phone vertically, but it just isn't programmed to do so. If you want to do complicated movements, maybe start looking at a standing person's feet, scrolling up their body to the top of their head, then down the back of their body, you need to look at what the gimbal can and cannot do.
  • Panorama mode. Controlled by the app, the gimbal moves to different angles and takes pictures, then stitches them into a panorama. Seems like this would be a good task for gimbals but they all seem slower than doing this by hand.

Added 9 June 2020
  • Time lapse mode - with gimbals you can easily add motion to your time lapse. Otherwise you have to improvise using things like kitchen timers and you could only do panning, and at certain speeds.
  • Joystick controls - I originally wanted to buy the FeiyuTech Vlog Pocket, because it was the smallest, but it doesn't have any joystick. The joystick lets you manually adjust the angles (in some modes) without moving the gimbal, if your motion is restricted. Like you want to hold the gimbal in some way and have the camera pointed at your face. I think gimbals without joysticks can still be controlled by the app.

Heal Force Prince 180D Home ECG

This article has been in draft for 2 years, so I'm publishing it in unfinished form.

There's a good comparison of home ECGs at https://www.ndsu.edu/pubweb/~grier/Comparison-handheld-ECG-EKG.html but they only have the 180B, so it's up to unqualified me to try and tell you what this is like.

Technology is amazing, you can now buy an ECG for home use for the cost of a single consultation with a medical specialist doctor. Sure, they're not as good as a 12-lead but they're small, battery powered and cheap. Ok I'm not qualified to be reviewing this, I can't even read an ECG, but since nobody has reviewed this, here I go. I found this on eBay. Their website seems to be http://www.healforce.com/en/index.php?ac=article&at=read&did=458 but it's very slow.

Comes with: ECG unit, leads for continuous monitoring, a nice rigid case (something like a spectacles case), power adapter, 25 disposable adhesive electrodes, instruction booklet, USB cable, hand strap (like those you use for phones, looks a bit weak) no CD.

Power supply: 4 × AA batteries or included power adapter. I don't know if the adapter is available with different countries' plugs, but you can try searching for your local plug. Batteries can easily last overnight, can probably last 24 hours too. Ni-MH batteries are fine.

Summary: impressive software on the unit and in Windows, seems to have ok sensitivity. I wish it had more memory.

Basics: a simple ECG with 3 built-in electrodes that can quickly and conveniently measure 30-second ECGs between your right hand and: left hand (lead I), chest (lead V) or left leg (lead II). With the included 4 wires you can make continuous measurements of leads I, II, III simultaneously, or leads V1 - V6 if you know what you're doing. Comes with simple analysis software on board and more powerful software in Windows.

03 April, 2020

Airmotion Woobi Plus Mask

There are 2 main versions:
1. Woobi Play, the smaller one for children. It seems to have been released earlier and is more common.
2. Woobi Plus, the adult version, only comes in one size. This is the one I'm reviewing here.

This product is confusing, which is unfortunate for its marketing because it's sold under a few names. First of all, who makes it? When you search for it, 2 of the top websites (1 2) say Kilo Design created/designed it for/in collaboration with "Singapore health-tech startup Airmotion Laboratories". So Airmotion didn't design it, they're manufacturing and marketing it? But the packaging doesn't mention Kilo Design at all, not even in the design awards. The only hints of Kilo Design's contribution are the European design awards.
But the packaging also says "designed in Singapore".
As you can see from the pictures, there are 2 versions of the packaging, English and Chinese. The English one came directly from Airmotion. The Chinese one came from China (Qoo10). I expect the product to be the same inside. From the AliExpress reviews, it looks like the Chinese one has an additional small catalog.

It's also sold by Xiaomi, but Xiaomi doesn't seem to be involved in any way other than selling it. The AliExpress reviews of the Xiaomi one show the same Chinese packaging, with no Xiaomi logos.
Hmm I just realised a lot of things Xiaomi sells aren't designed or made by them, they're just distributing them.


Official price USD42, about USD35 on AliExpress, I got it for USD38 on Qoo10.
Shipping from China is very unreliable right now, mine was stuck at the airport for 10 days. Airmotion's official site ships from several countries. They had stock in Singapore so I got it in 1 day!

Rated to American N95 or European FFP2 performance (Test: GB2626 & Certification: KN95)
Filters last 15 hours or 14 days
I can't find anything about flow rates or resistance or test certificates.

From the website:
• 1 Woobi Plus Mask
• 1 Woobi Plus Elastic Sports Strap
• 1 Woobi Ant-Slip Silicone Head Pad - this is very effective and useful!
• 1 Extra Set Colour Caps - that's 1 big (intake) and 1 small (exhaust)
• 2 Micro-HEPA Air Filter
• 1 Storage Pouch
That's accurate for what I got. Both HEPA filters came sealed in individual green capsules. I opened one and put it in the mask before this picture. So, you get 2, individually sealed, filters. I also got a simple postcard.

Well, you can see for yourself. It has a unique, smooth design. The main thing I like about the design is it doesn't look that much like a respirator, if you're worried about wearing it on the streets.

One thing I don't like is, it's short. If you look at the pictures, it only reaches halfway between mouth and chin. Industrial respirators seem to reach or cover the chin. Actually it doesn't really affect the comfort or sealing. Maybe you can't open your mouth as wide.

Sealing is very good. It doesn't require the strap to be very tight.
You can test the seal by blocking the valves (good for general public without fit tests)
Main problem is it's a bit pinchy on my nose, making it hard to breathe. Wearing it higher up works better. But wearing it higher interferes with glasses (you need to wear eye protection as well, you know?), depending on your glasses. They're almost interfering with mine.
The silicone pad for the hair is a very important and successful part of the design. A problem with all respirators - hair is slippery, the back of the head is rounded, the top strap tends to slide down. If you look at industrial respirators, they have a sort of cap/plastic loop that stays on the top of the back of the head. Woobi addresses this problem, which I've never seen a "home use" respirator even try before.
And it works! And it's even removable, if you need to change the strap, or find a better respirator that lacks this!

Breathing resistance is kind of high. I've been fitted and worn N95 masks before so I know what they should feel like. This is harder than the 3M 8210. So not that good in this aspect. Are the adult and child sizes using the same size filter?

I don't like the fabric elastic strap because it's hard to wash and dry and keep clean, which is what we're all trying to do these days.
This is as far apart as I can take it. As you can see, the valve holders pop right out. I can probably take the yellow and green valves out too. Everything is washable/doesn't absorb water except the filter and elastic strap. Elastic strap is washable too. Good and important for hygiene.

Only spare parts they sell are the filters. The mask itself comes with an extra set of caps, but you can't buy more. Seems like they should sell the elastic and valves too. I know industrial respirators sell almost every replacement part.

The exhalation valve cap is kinda noisy. Not the valve itself, I think the holes in the cap are too small. And it's not that important, ok it keeps the valve clean and protects it, and it holds the strap loop on.
I'm testing replacing it with just a piece of cloth.

Update 8 April 2020
I noticed a few more things. Firstly the adult and child versions seem to have different straps. The adult has an elastic fabric strap and the child size seems to have a silicone strap. A good thing I've noticed about the strap - even when you adjust it, there are no dangling ends, because it's attached to itself (like those messenger/sling bags). It's much neater and more hygienic. The strap secures by looping around the intake filter. It's secure, but a bit asymmetric because the intake and exhaust valves are different sizes. You can sort of dangle it around your neck if you don't want to wear it or carry it, but this may not be secure. I've done it and it's never come off. Because the strap is only attached to one side, it's very long when you take it off. Just something to note.

Filters last 15 hours at AQI of 200, which is at the extreme end of moderately polluted, so they'll last much longer in normal air.

31 March, 2020

iPhone: Copy Phone Numbers Without Spaces

If you save a number in your iPhone, it has this brain dead "feature" where it will add spaces to the number for you. 12345678 is displayed as 1234 5678, and if you try and copy the number, no matter what you do, it'll copy as 1234 5678. Now what's the point of putting spaces in phone numbers? Which system uses these spaces? Do you want to put spaces in emails too?

What's the problem with spaces? I'll tell you. In forms and fields with only exactly enough space for a phone number, the last digit gets cut off because of the completely unnecessary space. The number is now 1234 567.

Fortunately, I've found a solution. If you use an email field (or even custom fields, I guess), it treats the numbers exactly as entered and doesn't molest them. This is the equivalent of forcing a cell in Excel as text format.


22 January, 2020

Good Riddance, Google Photos

After 10 years, I've given up on Google Photos and It. Is. A. Relief. At this point, it's one of their abandoned projects on life support, like Google+. Hoo boy, remember that? Why you should leave Google Photos too:
  • I can't upload anything from iOS. What's the point? Ok, strictly speaking, there's a workaround: I can upload things to no album, then force restart the app, then move them to the correct album.
  • Speaking of no album, their organisation is still a mess. What a pile of crap. You can't see which photos don't be long to any album.
  • You can't see what albums a photo belongs to. At this point, albums are basically tags. You can see what tags a photo has, right? Why (*$^ not albums?
  • Sorting within albums is crap. The option to rearrange photos is hidden in edit mode. YOU CAN'T EVEN SORT BY FILENAME!
  • You cannot sort albums on the website. You cannot change album sort to descending in the app.
  • The interface is useless and there are a bunch of hidden albums. If you try and export your photos using Takeout, you'll see lots of albums with a date as the name.
  • We're still using that ridiculous tile interface that doesn't let you count photos at a glance?
  • No other display options. No different thumbnail sizes, no list. I can't even see filenames to quickly compare backups.
  • It STILL can't handle burst photos on iPhones. Basically, all it sees is the one single photo iOS chooses as "best". Choose another photo? The entire burst disappears. Convert the burst to individual photos? Nope, still only one photo.
  • You used to be able to trick it into seeing the other photos in a burst by duplicating them, and they've "fixed" this solution.
  • You cannot filter and see photos that have/haven't been backed up
  • I see they've helpfully removed the "not backed up to cloud" icon on photos, so now it looks like all your photos are backed up, when in reality they only show a "backed up to cloud" icon now.

Update 6 Feb 20
Another reason why:
"Google confirms it sent private videos to people in Google Photos"
Google sent people's private videos to strangers by mistake.

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