Monday, December 1, 2014

Droid Turbo Review: Disappointing

This is how Droid Turbo is marketed
This is what Droid Turbo is
I recently upgraded my Droid Ultra to a Droid Turbo.  There really wasn't a reason aside from Verizon's offer of a minimum $100 trade-in on any older phone - and I happened to have a Droid 2 which I kept purely as a backup phone.  My grand plan was to trade-in the Droid 2, and make the Ultra my backup.

Turns out after a few days getting acquainted I find that the Droid Turbo isn't a great phone, they made a bunch of tweaks and compromises which make little sense, and the mess Verizon made of my account during the transition is astounding.

Let's talk about the positives.  Droid Turbo has a great screen - high pixel density, great color, and a deeper black than the Droid Ultra.  It's only slightly larger than the Ultra, but the display makes it feel more like a tablet than a phone.  Battery life has been great - normally I'm hunting for a refresh charge right before dinner, but the Turbo is still above 50% and I've been on it for almost 12 hours.  It feels good in my hand, and I like the forward-facing speaker.  I also like their tweak of "Active Notifications" called "Moto" which shows multiple icons for notifications, where Active Notifications only showed the most recent.

My biggest complaint is with the Turbo's radios.  First and foremost, Turbo does not support simultaneous Voice + Data!  This is a huge problem in my eyes - apparently the phone does not have a dedicated CDMA radio for voice.  According to various peer/consumer forums Verizon will issue an update in a month or so that enables Advanced Calling 1.0 aka Voice Over LTE (VoLTE) and supposedly this will bring this so-called flagship phone into 2014.  It remains to be seen if the simultaneous Voice + Data will work when the phone doesn't have 4G LTE coverage, or for that matter if AC1.0 can seamlessly hand-off a call to a 3G or 2G site.

I've seen other radio oddities in the Turbo.  I wear a Pebble smartwatch and the Bluetooth connection was so unstable I had to turn off "loss of connection" alerts because I was getting them constantly - even when the phone was in my pocket.  GPS accuracy is notably degraded; in a side-by-side with my Ultra it's clearly off and tends to drift around.
More APs seen by another device
Droid Turbo sees these APs

Wi-Fi is also problematic.  I did a side-by-side comparison in the 2.4 GHz band and the Droid Turbo clearly sees fewer access points.  From what I can tell the Wi-Fi radio is almost 10 dB weaker on receive than other devices I tested.  I did not have an opportunity to test the 5 GHz band.  I will say on a positive note that Speedtest.net measurements were faster on the Droid Turbo versus the Ultra.

Looking at the GUI (aside from the aforementioned pixel density and clarity - which are great) I've found that some apps (notably Ingress) are having trouble registering screen taps.  It's not that the screen or the OS is lagged - it's just that certain actions such as tapping on a portal in Ingress just don't register.  I'm guessing that this may be fixable on the app development side, not the phone, but for now it's really annoying.

Turbo has a proximity/environment sensor feature which supposedly allows me to dismiss alerts/rings with a wave of my hand, however I find that it only works in ideal situations like when the display is facing up, and I'm in a well-lit room.  It doesn't dismiss if the phone is mounted in my dashboard holder, or in a dark room.  This wouldn't normally be a problem except that the default alert and ring are an amazingly loud and annoying musical tones - the first time I got a call was during dinner with my wife and I'd forgot to silence the ringer.  I sat there waving at the Turbo like an idiot while people at other tables (and my wife) glared at me.  For some reason the nearly universal trick of "tap the volume control to silence the phone" doesn't silence the alerts or the ringer.

Droid Turbo's "Command Center" widget is another disappointment.  It's a neat idea: weather, time, date, and battery level all in one, with pop-out drawers for weather forecast and upcoming calendar events.  Problem is that the widget is a 4x2 size so it consumes half the screen, and when the screen is off the drawers automatically retract.  Given that the widget takes up 4x2 regardless of whether the drawers are extended or not, this quickly went from "neat" to "annoying" - why not just leave the drawers extended?

On the business side Verizon managed to really screw up my account while processing this upgrade.  I was on a 2 GB plan with a 2 GB complimentary bump-up, and a 10% reduction on the monthly line charge.  The plan I had came with a Hotspot subscription.  I was assured by the corporate store rep that the upgrade would have no effect on my plan.  After the upgrade I got bumped down to 2 GB, my complimentary 2 GB bump-up disappeared, my 10% reduction disappeared, and I haven't been able to get my Hotspot reactivated despite calls to both Customer and Tech Support.  I've been so disappointed with the Droid Turbo that I tried to switch my service back to my Ultra - but Verizon's website states that I have a "pending order" which prevents changes to my account so I'm stuck with the Turbo for now.

I really wanted the Droid Turbo to be a great phone.  I suffered through the early Motorola models like the Droid and the slightly-better Droid 2, was mostly pleased with the RAZR Maxx, and was very happy with the Droid Ultra.  Droid Turbo is several steps backwards for the Motorola product line, and I think indicates that the transition to Lenovo leadership is having negative short-term effects.

Wednesday, July 30, 2014

AT&T - The Adventure Continues

Last weekend we had two visits from two AT&T techs, and another today.  The first visit was from a premises tech who concluded that our internal wiring was sub-standard, so he and I climbed around and drilled holes to run a length of CAT5e cable from the DMARC (aka MPOE) box to a new isolated jack.  He put a line filter into the DMARC itself, which makes the install very clean.  Afterwards he found that our feed line had a couple of bridge taps which would need to be removed, so he submitted a service request ticket for that.

Observation: The premises tech was a younger guy, and in the usual banter of running wire he told me he'd been in the US Marines where he did communications and technology work.  During the clean-up phase of the wire install the tech managed to staple into the CAT5e itself.  It happens, and it's not usually a big deal since you have four pairs to work with - you just pick another pair.  I suggested that we "ohm out" the wires since we still had easy access to the ends, and that way we could avoid a debug session later.  He didn't have an ohmmeter with him, which I thought was odd.  Checking the wire pairs is fairly easy - you strip the insulation from the ends, twist one end of each pair together, and then measure resistance of each pair.  If any are obviously higher than the others, that's your problem pair and you avoid it.  Turns out he had no experience with things like this!  His military technology education had been along the lines of "If this box goes bad, remove it and install a new box."  When I went through US Coast Guard electronics school in the early 80's we were taught basic electronics, Ohm's Law, circuit-level troubleshooting, and even vacuum tube circuits before moving on to systems-level work.  Clearly a major shift in military training has occurred since then, and not for the better.

On Sunday the line tech showed up.  He removed two bridge taps from our line, and also cleared out a rodent nest from the pole-top splice boot.  He declared the line clean, although the signal level seemed a bit marginal (about 10 - 11 dBm).  As the day went on I monitored the modem's diagnostic page and noted that we were getting a LOT of forward error correction (FEC) errors.  FEC errors are considered correctable errors (unlike CRC errors which are uncorrectable) but they still cause lower performance and indicate something is wrong.  Tuesday night the network went offline - the logged FEC count in 48 hours had reached almost 100,000 and the connection speed was below 1 Mbps.  I tested using the modem's diagnostics and saw IP errors, IPv6 errors, and a lot of DNS failures.  Back on the phone with AT&T...

By now I've been on the phone with AT&T enough (almost every day) that they've given me a special Tier 2 support number and a passcode for it.  This gets me straight into their domestic tech support line, which is nice.  Another call to Tier 2, more tests from their end, another tech visit scheduled.  Today's tech agreed that the FEC errors indicated a problem, and was about to call in an order to have my DSL line card swapped at the central office.  I asked him if he had seen a lot of problems with the NVG510 modem.  (He thought I'd already had a modem swap, but I hadn't.)  I asked him if he considered the NVG589 more stable.  The NVG589 is only for VDSL installs, but he said "Hold on." and came back with a new 5168NV modem.  From what I've read, these are the "go forward" modems which AT&T will standardize on since they support everything from ADSL up through VDSL2.  The 5168NV (datasheet) also offers 802.11n 2x2 MIMO, 400 mW Wi-Fi power, and has a dual-core processor which speeds up recovery from retrains and allows faster adaptation to spectral interference.  One side benefit of the 5168NV is that the downlink receiver has much better performance than the NVG510 - I'm seeing +18 dBm on the downlink versus the previous 10 - 11 dBm.  So far the performance has been very good, Netflix picture quality is a lot better, websites are more responsive, etc.

Sunday, July 20, 2014

Thoughts on GoTenna

[Update Nov 30th 2016: The ARRL has asked Bay-Net to attempt a modification of the GoTenna for use in the amateur radio bands.  Also I should note that since I wrote this article, GoTenna has backed off on their performance claims to levels which are more in line with reality.  I'm looking forward to seeing the inside of these units and doing some real world testing.]

[Original Article posted July 20th 2014] GoTenna seems to be doing a good job of generating "buzz" for this proposed product - a cursory search of Google+ and Facebook turned up a HUGE number of posts.  Many people have forwarded this to me via email or social tagging.  The proles are calling it "Text messaging for CB radio".  facepalm

GoTenna's radio works in the MURS band - three channels at 151 MHz and two channels at 154 MHz.  Given what I know about their product, MURS rules will require them to operate on the two 154 MHz channels.  They say the product emits 2 watts, which with a 3 dB antenna would be 4 watts effective radiated power (ERP).  At that level they're going to have to undergo safety exposure testing, which is expensive - I guess this is why they're crowd-funding the project.

To be fair - GoTenna has an engineering advantage in that they're not dealing with large data streams - they send GPS coordinates, text messages (< 200 characters), and it's not real-time.  They claim 20 - 30 mile range in a "typical" urban environment - I'm struggling with the idea that something which emits 4 watts ERP can give you 20 - 30 mile urban range.

Coding gain from a forward error correction engine could help, but I can't imagine an effective coding gain of more than 10 dB.  (The device is battery-powered, and claims a 30 hours continuous on time - processors which could give them > 10 dB coding gain are going to wipe out a battery fairly fast.)  Let's be generous and say their coding gain 10 dB - this gives effectively 40 watts.  I suppose depending on your definition of "urban" this might be enough to cover 20 - 30 miles.  A more reasonable coding gain will be in the 6 dB range, which means effectively 16 watts - and I don't see 16 watts covering urban areas very well.

Here's a post on Make.com from Raphael Abrams, the GoTenna RF designer: http://goo.gl/L5rZ2e

GoTenna claims that the device can be used in-flight on commercial airliners.  This is a Bad Idea™, and I don't see the FAA signing off on this any time soon.

Lots of speculation on GoTenna right now in the radio community, but not many answers to the head-scratcher questions.