Review: Mi Band Pulse Fitness Tracker (XMSH02HM)

Up until now, I have been a regular user of my Xiaomi Mi Band fitness tracker that I reviewed back in 2015. It was simple, good value for money and performed consistently although the silicone band eventually wore out and the battery life started to decrease but not unacceptably so. For the price at that time, it really could not be beaten.

Since then, Xiaomi have refreshed their lineup of Mi Band fitness trackers to bring two new ‘1S’ models that come in two variants – one with a heart rate monitor which is listed for CNY99 (~AU$20.99) and another without, listed for CNY69 (~AU$14.63).

Thanks to Xiaomi Singapore, they have provided me one of their Mi Band Pulse fitness tracker units for review – so I’ve set my original Mi Band aside and worn the Mi Band Pulse exclusively to track my daily activity. This was a relatively long review to complete – taking almost two months of time.

Unboxing

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The item arrived in a wallet-sized box with full shrink-wrapping around the outside.

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In keeping with Xiaomi tradition, the box is cleanly branded with the Mi logo on the front of a relatively plain wood-pulp coloured box with the specification label on the rear. A small departure from the norm is the fact the label is now much bigger featuring specifications in English as well as numerous approval logos not seen in the past. It’s a key indication of Xiaomi’s intention to target a more global market.

The specifications, for the most part, remain very similar, boasting a 5V 25mA typical input charge current, IP67 water resistance rating and compatibility with Android 4.4 with Bluetooth 4.0 LE and iPhone 4s and newer running iOS 7.0 and above. A slight difference is seen in battery capacity, with a bump up from 41mAh to 45mAh (+9.76%) although given the increased hardware of a heart rate sensor, the expectation is that the battery life may not be as good as the original.

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The packaging is virtually identical to the original, featuring the sensor itself on the top flap, and the included accessories underneath. Good to see that there weren’t any unnecessary changes made.

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The biggest difference, by far, is that the user guide provided is now bilingual – open from one side for Chinese and the other for English which should make things a little easier for those who still need guidance. That being said, there are some subtleties to be aware of – for example, that the metal contacts should face down when being inserted into the band otherwise the “flick” wrist gesture may not be detected and the LEDs may not activate.

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Putting the new and old side-by-side, it isn’t immediately obvious which one is which. I think the design aesthetic in this regard is commendable, as it is rather discreet and not “shouty”.

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From the side, however, the new unit is clearly differentiated by its greater thickness, but this shouldn’t worry you.

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Like the original, charging pins are aligned at one end, and there is a “slot” or channel around the face where the wristband silicone edge rests inside and forms a nice seal.

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As shipped, the heart rate sensor window on the rear has a protective label covering it which must be removed prior to use. The approvals are again printed on the label and also laser-etched into the body of the unit.

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As a result of the changed body shape, now featuring a bulge, the charging cable has been slightly redesigned. It has a flat short cable segment instead of a rounded cable in the first iteration, and now has a recess for the sensor bulge to sit into when being charged.

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The cable will still charge the original Mi Band 1, although charging the new Mi Band 1S Pulse with the original cable is not physically possible.

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2016041520113237A macro photo through the sensor window shows two LED dies mounted on opposing corners of the substrate, with the sensor being a relatively large area array situated in the centre. Some sort of black foam square with a circular aperture is used to exclude light spill from the LEDs getting directly into the sensor without passing through the skin first. The sensor itself seems to have many wire-bond connections, implying that the sensor itself may contain some logic within it.

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Now, we move onto the band itself, which looks virtually identical to the original. I can’t seem to spot any obvious changes, it even has the text “designed by xiaomi” in the same place.

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Fitting the sensor into the band completes the set-up process, and it’s more difficult than in the previous model due to the tighter fit around the rear. The rear bulge now purposefully uses the cut-out in the rear of the band and “fills it in”, so it is not wasted space.

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This results in the rear sensor being flush to just slightly proud of flush to the rear of the band, making for a comfortable fit and good skin contact.

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Compared to the previous Mi Band, the weight has increased by less than 1g, and the entire assembly now weighs 14.54g.

Software

mi-versionThe band is used with the Mi Fit app, which is available from the Google Play Store and Apple App Stores free of charge.

As of reviewing the band, Xiaomi just released a new update to the application which makes significant changes to the user interface and functionality. This version is 2.0.0 and was still the current version at the time the review was published. As this is the first release of this majorly overhauled app, it can be expected that some issues might occur.

Unlike the previous review, several things have changed. For one, I have a Mi branded phone, which features integration with the Mi account, streamlining the set-up process. Aside from this, I also already had a Mi account set-up with the old Mi Band, so I am upgrading from one to the other, which results in a few less steps in the set-up process.

To set-up, the first step is to fully charge the band, then download and install the app. From there, it’s as simple as following the prompts and registering/verifying a Mi account if you don’t already have one.

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Right after set-up, the device gets a firmware upgrade as the phone app has a more recent version of firmware on it than the band. Be sure to keep the two close together during the upgrade. After the main band firmware updates, the app also wishes to update “heart rate”, which is a separate piece of code in control of the heart rate sensor.

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mi-homeOnce everything is updated, then we are ready to explore the new version of the app.

The main screen you are greeted with on opening the app is the “Status” page. This features a dial display of the number of steps you’ve completed, with summary of the relevant stats underneath. Below that is a graphical and numerical summary of last night’s sleep data, along with a weight trend graph (really useful if you have a set of Mi Scales, although manual entry of weight also works). Underneath that is the heart rate module, and below this is the “streak” graph.

Each of these elements can be tapped on to open a more detailed view. For example, the animation below shows what happens when you tap on the steps area which brings up the detailed step trend data.

Unlike previous versions of Mi Fit, this now keeps detailed step trend data historically as well, so you can review your step trends into the past in detail rather than in aggregate.

Of course, the aggregate values can also be seen by clicking on the stats button and reading the values from underneath the graph area.

 

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This same feature also extends to the sleep data area, which has the same sort of layout.

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mi-hrmClicking on the weight icon brings up a similar display with the weight trend, as well as BMI and body type information. There is also an easy way to add a new weight reading from this screen – but I didn’t capture a picture of this screen (for obvious reasons).

Finally, we move onto the heart rate measurement area, which is unlike the above areas yet again. On first measurement, you get a short tutorial on how to use the heart rate monitor properly, but after that, it’s a very simple area where you can manually invoke a heart rate reading and get it on the screen mi-sharingafter 6-10 seconds with a scale indicating the intensity of the activity. Previous readings are stored in a historical list.

In most screens, in the top right hand corner is a share button, which brings up a summary of your data, how it compares with the rest of the users, and buttons to share it with a pre-defined list of services.

The second tab is the “Play” tab, which has several different features which can be configured.

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mi-screenunlockThe top section allows you to enable the band notification features – whether it vibrates on incoming calls/SMS/app notifications, whether you have any alarms set, and whether to vibrate if a phone alarm sounds.

Underneath this, you can configure whether to use the device as a Bluetooth proximity device to unlock your screen without needing to enter a passcode – it was simple to set-up and worked just fine with my RedMi Note 2, although the unlocking action is not instantaneous.

The Bluetooth discoverability can be changed as well, and it’s good to see it defaults to off, as this setting makes it less likely that others can use the band to monitor your location. Leaving it as hidden, however, can make it impossible to find using regular Bluetooth Low Energy scan applications if it should get lost.

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Data sharing with WeChat, Sina Weibo and Google Fit are now offered, to allow you to challenge and compete with users on these services and synchronize your data with Google Fit so you have another way to access your data.

mi-profileThe final tab, labelled “Profile” has access to your profile as well as settings and device information. Here, you can see (at a glance) your daily average steps, total distance walked and number of days you have reached your goal. You have a listing of your paired devices and their remaining battery with the option to pair new devices.

You can set your goals, and notifications, as well as connect with Mi Friends.

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device-informationIf you tap on the device itself, you get much more information about the device, and the ability to toggle options such as band location, Sleep assistant (heart rate monitoring during sleep to improve sleep data) and whether your phone displays notifications when the band vibrates. Find band also allows you to trigger vibration on the band if it is in range, to allow you to recover a missing band. You can also unpair a device from this screen to prepare it for reuse by someone else or migration between phones.

Settings allows you to control the units used in the display of the app.

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Finally, feedback allows you to fill in a form to provide feedback to Xiaomi about the app.

User Opinion

zbattery-rundownA big reason why this review took so long was that the battery life of the band was much better than expected. In fact, as the screenshot to the left proves – I achieved 40 days of use before falling below the 10% low-battery threshold, suggesting a “full to empty” life of about 43 days which is on par with the original Mi Band without heart rate sensor under similar no-notifications, one-alarm-a-day conditions.

You might be inclined to think that I did not make utilization of the heart rate feature. In reality, I did use it in two ways – since the beginning of the test, I had Sleep assistant turned on, which consumes battery in order to improve the accuracy of the sleep data by measuring heart rate during sleep. I also manually initiated heart rate readings a total of 146 times (3-4 times a day) according to the logs. This would be considered “reasonable” for manually invoking the feature, although automated means with periodic measurement is likely to increase that dramatically.

Additionally, I also made use of the Bluetooth unlock feature which, while generally functional, was not quite as instantaneous as one might like. However, this does involve communication at every unlock of the phone, which consumes power. On the plus side, not using the notifications feature and only having one alarm per day drastically improves battery life (as the vibration motor is the largest battery drain). I also did not invoke the LED display too often.

With these results alone, it was pleasantly surprising to see that the band with the heart rate sensor was really at no great disadvantage from a battery life perspective despite the incorporation and use of these additional features. It seems plausible that if you did not use the heart rate sensor and turned off Sleep assistant that the battery life may be better than that of the original Mi Band even when new. Whether the band can maintain this level of battery performance into the future remains to be seen, as the original band of mine has decreased to about 50% of its original battery lifetime. That said, as the capacity of the battery in the Mi Band Pulse is different, it’s likely the supplier of the battery has changed, so this problem may not be an issue for this new unit.

The physical design of the wristband itself does not seem to have changed, and while it is simple, secure and unobtrusive, its durability is still potentially under question. My original band lasted around half a year before slowly falling apart (first the loop, then the holes which the buckle uses became too wide and finally the edge around the sensor developed tears) and needing replacement. I would recommend that you do not remove the band from your wrist at all to maximise its lifetime, and merely pop the sensor out for charging when absolutely necessary. It is good to know that replacements are available, although finding a genuine replacement can be a little difficult and its price is a significant fraction of purchasing a new tracker altogether. At least, the replacement bands come in different colours, if you should wish to customize.

The band itself tracks steps and sleep seemingly with equal reliability as the original Mi Band which was more than satisfactory enough. The improved accuracy of the Sleep assistant was not immediately obvious, however, given there was no major deviation of the data, it seems that it has not negatively impacted on the accuracy. Changes were made to the display, now with white LEDs instead of the RGB “colour selectable” display in the original Mi Band. This change is welcome, as the colours were not put to any good use in the original, and the white LEDs are slightly more easier to see under lighting – although you will still struggle under direct sunlight.

Personally, I was not too convinced about the need for a new Mi Fit app, as the original one performed quite adequately in most regards and was approaching a level of stability and dependability. The new app does have several improvements – of course, it comes with new firmware, but it also now has detailed historical daily trend charts of steps and sleep data, so you can access details rather than aggregate step counts only. It incorporates the new heart rate abilities as well, and the redesigned main page adds additional emphasis to weight as well (especially useful should you have a set of Mi Scales to go with it).

While the unit advertises heart rate monitoring, the way the application performs the heart rate monitoring is somewhat disappointing. The heart rate monitoring is a separate area where you can manually invoke measurements of the heart rate, which are displayed on the screen after 6-10 seconds. The heart rate can be shown on a scale indicating the level of intensity of the exercise, but nothing more. The heart rate is just a number next to a date and time – no trend graphing is provided for, and no periodic monitoring of heart-rate is provided. Given the battery size constraints, I could potentially understand why they didn’t choose to offer this mode, but given these limitations, the heart rate monitoring is less valuable than it otherwise could be. Maybe they should address this and provide trend plots and automated reading in future versions of the software (with a possible disclaimer on battery life). Further to this, the list of heart rate data points does not seem to be able to be exported for analysis elsewhere from within the app, and any heart rate measurements taken to improve sleep analysis are not recorded either.

While the new Mi Fit app is not especially poor in any way, and is still intuitive to use, there are a few unexpected bugs in Mi Fit 2.0.0 and the way it works with my Mi Band Pulse. These include problems setting/clearing alarms resulting in the wrist band despite receiving visual confirmation that the operation had succeeded – this results in the band “going off” on old alarms which had been turned off, or at the wrong time at some occasions, resulting in confusion and being woken up needlessly. Accessing the alarms, resetting each and every one of them and toggling them on and off seems to clear the problem only until you make another change to the alarms. This was not a problem with my old Mi Band and Mi Fit 1.x series app – I suspect this may be easily fixed in future revisions of the app and firmware.

Speaking of alarms, one feature of the original Mi Band and Mi Fit 1.x app which seems to have gone missing is the “Early bird alarm” feature which tries to wake you up to 30 minutes before your alarm during a shallow part of your sleep cycle so you wake better. While I didn’t use this feature very much, to see it seemingly disappear under Mi Fit 2.0.0 might be somewhat disappointing to some users.

Other issues include graphical update glitches when scrolling around aggregate data graphs, where slowly moving from one graph bar to the next results in the figure summary not updating as it should. Moving quickly, or flicking away from and back to the same bar often results in the figures updating properly. This is not a critical issue, although it does detract from a seamless experience.

It’s nice to see that the band operates in non-discoverable mode by default, improving wearer security against tracking, although this also seems to have a negative side effect that connection and updating data from the band takes tens of seconds when launching the app. Under areas of high interference (or maybe it’s an issue with the phone after a while), the process of updating data from the band may need to be retried, or the Bluetooth functionality on the phone may need to be toggled on and off to restore connection.

While none of these issues are necessarily show-stopper issues, they are issues which need to be addressed sooner or later to maintain an optimum user experience. That being said, there’s nothing particularly wrong with the core functionality – that of step counting, heart rate reading and sleep tracking.

Conclusion

The Mi Band Pulse is a step-up from the original Mi Band. While the new ‘1S’ models are available with and without heart rate tracking, the difference in cost is so miniscule that it’s probably best if you just bought the one with the heart rate sensor even if you don’t use it. The price is still very much in the ~AU$20 category which makes it highly affordable especially compared with other heart-rate capable devices on the market.

The thing that I like most about the Mi Band Pulse is that it externally assumes the same form factor as its predecessor, and is just as unobtrusive and comfortable to wear. The heart rate sensor functions well, even without excessive pressure, using up the previously “wasted” space in the rear of the wristband to make contact with your skin. The weight has not increased perceptibly, and best of all, the battery life has not worsened at all compared to the original without any heart rate sensor, remaining steadfastly in the 40-day region.

I wore the unit continuously and it was capable of standing up to the daily torture of warm to hot showers, cold hand washes, and bumps against things without failing. There was no sign that anything was amiss with the sealing, as even the addition of the heart rate sensor window did not affect the waterproofing performance.

That being said, there were a few drawbacks and potential issues. The new Mi Fit 2.0 application is not entirely free of bugs – problems with statistics updates when the charts were scrolled slowly were evident, as was problems with setting alarms which claimed to have correctly set but occasionally lead to the wrist band actioning alarms which were turned off or going off at the wrong time. In that regard, the original Mi Fit 1.x series application was more refined and did not exhibit these issues, but I suppose these are easy fixes which will eventually trickle down to users.

Heart rate monitoring could be better integrated into the app – at the moment, measurements are taken manually which limits the usefulness, and no ability to graph the data or bulk-export the data is provided. It is merely a table of dates/times and measured heart rates. Paid-for third party applications have tried to fill this void, however, this should not be necessary for a product such as this, where periodic heart rate graphing may be an expectation rather than a wish (e.g. compare Apple Watch).

As both the original and 1S models share the same wristband design, the durability of the band may be a consideration, as replacement after a few months of use seemed to be the norm for me. That being said, replacement bands are available in a range of colours, so it’s probably no big issue, although getting a genuine replacement does take some effort and is highly recommended to ensure the best fit and durability. Concerns with the battery cycle life shown with the original Mi Band may also resurface with the 1S models, although it seems that the batteries are likely to be different due to the different stated capacity, so I will give them the benefit of the doubt on this one.

I suppose the thing readers would be most interested in is whether they should buy this unit. Given my experiences with it, I would have to say that for the price, it’s very compelling. The software may not take the best advantage of its features, but this could well change into the future, or with the use of third-party software. Is having the heart rate measurement actually important? It can be depending on whether you have an interest in how hard a given workout is pushing your cardiovascular system. But even if you don’t use it, there is really no great penalty from buying the one with a heart rate sensor.

The biggest thing that might put prospective buyers off a Mi Band 1S? The fact that the Mi Band 2 is expected to launch early June (in China only) and features an OLED display rather than the simplified 3-white-LED display of the 1/1S models. That being said … given the price, maybe you can afford to buy both? 🙂

Thanks to Xiaomi Singapore for providing the unit for review.

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Failed: Cheap and Nasty SMA Right-Angle Adapter (& Site Update)

If you’re a bit of a radio equipment user like myself, you’ll find that you’ve always got an amazing array of different connector needs. For example, you might have some older TV tuners with a “PAL” connector, some satellite equipment that uses an F-connector, a spectrum analyzer with an N connector input, a few old scanners that use BNC, an HF set that uses a PL-259, a GPS which uses MCX, and some new SDRs which need MMCX and SMA just to name the most common. Then maybe you’ve also got Wi-Fi equipment with RP-SMA to deal with as well.

To stock all the necessary cable variants to interconnect each and every sort would be prohibitively expensive, so in general, we get around this with adapters and “pigtail” leads. These can be rather difficult to obtain for some combinations, especially “inter-series” where impedances are not matched, and some creative “adapter stacking” might be necessary to get the desired end result.

Having realized all of this, I’ve always looked upon the catalogues in some electronics distributors and felt rather offended that some rather “simple” adapter cost almost AU$50, or sometimes, almost AU$200! This was especially true when I found the same adapter retailing on eBay or in a variety shop for under AU$5 … so I take the cheap road and that’s the end of that. Or is it?

Is there a problem?

Many people will do exactly the same thing as I did – go to a cheap variety shop, pick up some adapters, splitters, connectors, etc and plug it in. Maybe it works, maybe it doesn’t … maybe they decide to throw in an amplifier, blame “physics” for signal loss and everything seems to be swell. Ignorance is bliss.

But in reality, RF connectors are very very precision devices. For consumer applications, where sending or receiving a signal is the aim, the requirements are not so stringent. This is because the signal coding frequently is designed to withstand some losses and effects from inferior connections and cables, the bandwidth the system needs to operate in is limited, the amount of reconfiguration of connections is limited and low cost is the aim. Many users won’t notice the difference between a few dB of loss here and there. But when you absolutely need the best performance, these things can matter.

For those who want the best DX, who may be operating transmitters and repeaters where signal loss, leakage and reflection are undesired, or doing measurements using analyzers over a wide bandwidth, performance of the connector is paramount. A connector, at RF frequencies, cannot be treated as a simple joint in the wire.

RF frequencies involve quickly alternating currents, and due to the physics of the way these signals propagate (e.g. skin effect, transmission line effects), the connector itself has to perform the function of matching impedance. To quote a water-pipe analogy, the connector itself has to be “the same size as the pipe it joins”, otherwise the water pressure will be reduced, and transients in the pressure will “bounce” back and forth from the interfaces (creating standing waves, and being resistively lost).

In order for connectors to properly match impedances and minimise frequency-related variations in transmission losses, their dimensions have to be critically controlled. The size of the pins, collars, slots (if any) and dielectric (if any) size and material are controlled to produce the best match possible.

Sadly, the low-cost options don’t control for these dimensions as well as they should.

Bad Connector! *smack*!

While playing with a new SDR which uses SMA connectors, I decided to use a bunch of right-angle adapters to make wire connections more convenient. These are relatively simple adapters – what could go wrong?

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Alas, I ended up scratching my head at some very strange frequency response curves at several gigahertz frequencies, and intermittency in connections when they get “bumped”. As SMA connectors are semi precision, they shouldn’t do this, so I took the connectors apart to take a look.

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One of the two looked fairly okay, although this is pretty much a generic consumer grade connector. Note how the centre socket is ovular, has some slits in it, and the dielectric doesn’t fit so well around it. It also has some traces of gold dust on the dielectric, suggesting the fit isn’t so good and it’s wearing out with each insertion and removal (as expected).

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But the other one was so far off, that the mating pin had crushed the socket into the side and expanded the dielectric somewhat. That’s what happens when your dimensional accuracy gets a little too slack.

I’ve also had pig-tails made of unidentified coax for RTL-SDR style dongles with PAL to MMCX adapters, but these were so bad that the MMCX end oxidised (not real gold plated) after a few months of service, and the “coax” itself lost so much in the UHF ~600Mhz band that it went from perfect reception on another tuner to no-lock whatsoever (estimated >20dB of loss).

Another MMCX to F adapter I purchased fell apart after a few months, with the MMCX collar separating from the nickel plated body of the connector under very little stress.

After you encounter these sorts of problem-after-problem scenarios, it’s easy to understand why more expensive reputable connectors (when available) might be the better choice, or in some cases, making your own adapter cables with quality branded connectors.

Conclusion

As I move from being a simple minded user with simple requirements, through to a power user with more difficult requirements, through to one who is even more demanding of their equipment in performing measurements, I begin to appreciate the differences between a more expensive adapter and their bargain basement counterparts. The cheap stuff being sold on eBay might work for some basic reception and bridging the “gap”, but if your goal is to do analysis or have optimal reception, they will easily work against you.

Worse than that, there is a real potential for connector damage by mating sub-standard connectors to higher quality connectors. Agilent’s connector grade FAQ details this to more extent, but the goal seems to be to use instrument grade connectors or better with instruments, and use suitable adapters sacrificially to connect devices under test to avoid damage to instrument connectors.

Even more than that, it shows how important it is to check your connectors before mating them, and clean them if necessary to maintain performance. RF will not easily tolerate bad connections in the same way an audio signal might.

Extra: Site Update

Apologies for the recent slowness and downtime. I have been tied up with too many things, and ultimately, didn’t have the time to investigate and remediate as quickly as I should have.

I am aware of a few people who have attempted to comment, only to meet into 500-type errors. The cause is mainly due to an increasing number of disrespectful robot traffic which does not obey robots.txt and will change their user agent if you try to block them via .htaccess. They have been making >33 requests per second which easily swamps the resources available from my “low end” shared hosting, which is causing occasional time-outs which are becoming more frequent. The worst part is that they claim to have slow crawl rates, but are anything but, and they come all at once, as if scripted to do so.

My robots.txt continues to grow, although I fear it is in vain. There are many legitimate robots which I cannot block, otherwise risk losing exposure for this site. There are also many illegitimate robots which cannot be blocked, because they disobey, or they don’t even recognize themselves in the robots.txt file.

Further to this, I also have contended with many bots attempting brute-force logins to the tune of over 70,000 attempts per day which is very unfriendly. While I have had some protection (mainly against brute force intrusion), it did not protect against generated server load. Reconfiguration of the server has been done to make it much more restrictive to hopefully regain some of these wasted resources for legitimate visitors.

At this stage, even though errors are occurring more frequently, mostly around 7-9am Sydney Time (UTC+10), I still cannot justify upgrading the web hosting just yet, as it’s handling with the load on a majority basis. The traffic for this site has grown to a ginormous 455Gb per month, so I suspect I’m doing quite well with that in mind.

It’s a shame that we live in a world where more resources are wasted on illegitimate visitors than actual humans, and time has to be taken away from discovery and experimentation to ensure continuity of service. But yet, seeing as I do learn in the process, it’s not all time wasted.

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Freeview Update: 7HD Sydney’s (sort of) Launch?

A few weeks back, a kind tweet from a reader let me know that 7HD Melbourne was on the air and broadcasting. While I was down in Melbourne, I wasn’t fortunate enough to be able to scrape together a transport-stream recording for analysis because of antenna and tuner issues, so I returned home underwhelmed, with the thought that I had missed an opportunity. The press generally seemed to imply that Sydney was among one of the cities that would have to wait for the launch of 7HD.

Interestingly, when I came home, and had a little time to decompress, I got out the tuner to find that indeed, the services on the air had changed, so it was worthy of a new reanalysis.

Results

station-wmarkUnlike that of Melbourne, 7HD in Sydney is a simulcast of 7mate, rather than the main 7 Sydney channel. As a result, it’s still mostly running the less interesting reruns. It seems that HD-worthy events may be casted on 7mate in the states where the new HD station is a simulcast of mate, otherwise on the main station where the HD station is a simulcast of the main station. At least, I hope that’s how it will work.

One piece of good news? The pesky TV4ME is now off the air, maybe for good. That gives us another 1.2Mbit/s or so back, so thank you!

As has been the main vein of the “HD revival”, the new stations all use H.264 encoding for the video. A few changes to PIDs occurred here and there, so the service table now looks like this:

ch7hd-svc-summary

Changes included:

  • Service names mostly changed to indicate the service area where it is broadcasted.
  • LCN70 is no longer a virtual service for LCN7/71, and instead maps to 7HD Sydney.
  • 7HD Sydney is a simulcast of 7mate, which is now converted to an MPEG-2 SD channel.
  • Text PIDs for 7mate, 7HD are changed, and AC3 audio is taken away from 7mate to 7HD Sydney.
  • As noted earlier, 7flix has gained an MPEG-1 Layer 2 128kbit/s Joint-Stereo stream to help alleviate the people who had vision but no sound, due to the choice of AAC-based audio initially. It was reported to have gone missing, but is back at last survey.
  • 7flix’s encoding profile has changed from [email protected] to [email protected] to gain a little more encoding efficiency, while being unlikely to provoke any compatibility issues.
  • Audio for the main channel is Joint-Stereo at the point I checked, but was claimed by others to vary continuously.
  • TV4ME is no longer carried.

Bitrate wise, things have been shuffled around as usual. The HD service is now receiving a very respectable ~7.4Mbit/s for the video stream alone, which is one of the best on the air at this moment because this is roughly the same bitrate the MPEG-2 HD service had but instead using a more efficient H.264 encoder.

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The rest of the SD channels have more or less been equalized to roughly 3.25Mbit/s total rate, and RACING.COM remains with its ~2Mbit/s allocation which has been unchanged since last year.

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The per-PID rate tables are shown – total bitrates are a little off because it’s based on imprecise “to the minute” recording times, but on the whole, multiplex utilization has remained high with the null padding remaining relatively limited compared to previously when (seemingly) Fresh Ideas went off the air but the bitrate was not reallocated.

ch7hd-muxarea

The mux area chart shows that stat muxing is in use, likely in an effort to improve quality. The results above are from an average of 3 hours of programming in prime time (6:53pm to 9:53pm), and are more representative of the true average without instantaneous peaks and troughs.

Conclusion

It’s nice to see that high definition in its true and full 1080i form is returning to the air, with all commercial broadcasters switching over to H.264 encoding to meet quality and bitrate budgets. Of course, older sets (such as that in my hotel in Melbourne) and set-top boxes are not compatible with the more advanced codec and they will miss out on these new HD services, and lose HD service entirely, but this is the way of the future. I suppose it remains to be seen what ABC and SBS will do about their services and whether they will embrace H.264 encoding.

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