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Australian TV Tuner Offers 4 RTLSDR Tuners in One Internal Card
Over at RTL-SDR.com is a report of a fascinating development with the DigitalNow Quad DVB-T Receiver, apparently well suited to working as a very powerful multi-SDR solution.
I just wanted to let you guys know that the Digital Now Quad DVB-T Receiver (http://digitalnow.com.au/product_pages/Quad.html) works. It’s a PCI-e card with 4 tuners on it, linked up internally via USB. This has pleased me no-end – I might finally be able to get DAB+ working on my media centre!
I had to add the following line to librtlsdr.c
{ 0×0413, 0×6680, “QuadDVBT” }
I wouldn’t be surprised if this patch makes its way onto the slightly more user-friendly Windows pre-compiled drivers before too long. If you live in Australia, or don’t mind paying for shipping, you could have one for AU $179, with the Australian Dollar roughly at parity to the U.S. version. For $45 per tuner it’s a great looking integrated solution and is much more elegant than a USB hub and a stack of dedicated dongles. Looks like this one has a PAL connector.
Hey, I Won Something. [Basic Micro ATOM Nano Development Board]
I read too much of the Internet every day, but it’s finally paid off. I happened to catch a post on Hack-a-Day about an awesome giveaway right as it was posted for a microcontroller development board. An interesting one, too – the Basic Micro ATOM Nano.
The dev boards come complete with an LCD header, a small solderless breadboard, USB connectivity, a pair of servo connectors, and more! The Nano 28 is based on the PIC16F886 microcontroller, and features an 8MHz clock, 24 I/O pins, 14K of flash memory, 368 bytes of memory, and 256 bytes of EEPROM storage.
The total value of the package is just around $50, so this is an incredible deal! Basic Micro will even ship your kit to you for free via USPS.
Not too bad. There were 55 available and I snagged one, and they’re now out of stock and won’t be replenished so I’m assuming they were clearing out these discontinued models to the community. I’ve been wanting a microcontroller board for a while, too – but the investment in an Arduino was more than I wanted to go for at once.
This changes that, and with USB connectivity and a nice looking IDE it should be pretty easy to write for. Microcontroller programming is a new thing for me and I’ll have to learn what’s possible with it. With a lot of IO pins but very little memory, this looks like it might be good for some kind of display or visualization or to send and receive data from sensors but not much more – that’s a tiny amount of memory by any standard, the equivalent of just a few sentences of text. We’ll see what’s possible. I like the integrated solderless breadboard area – this will make it easy to try out a few ideas immediately.
This might make a fun servo clock platform. I’ve had it on hand for a little while now but only just dug it out of the box I stored it in to start messing with, hopefully I’ll be able to start developing with it sooner than later.
New Toy + Starting a Project [1937 GE F-135]
I picked up a very nice 1937/1938 General Electric model F-135 radio from Craigslist a few weeks ago, and have been starting to dig into it. It’s one of the highest end radios they produced that year for the 1937 holiday season and 1938 production year: with 13 tubes, automatic frequency control to eliminate station drift, experimental hi-fi reception in 4 bands from 550KHz (AM) up past 40MHz (VHF) continuously, it offers a motorized tuning with 13 station presets and push-pull 6L6 tubes pushing 20W into a huge speaker. It should sound incredible when it’s all fixed up, and it’s the most complex and highest-end radio in my collection.
I found an ad mentioning my F-135, and showing the next lower model the F-96, in the Dec 1937 issue of Radio Retailing:
I used to have an F-96, actually, but sold it unrestored for the same price I paid for it without touching to free up some storage space – a decision I still regret, but have rectified by getting a new F-135. It’s a beast of a radio, stored fairly well but with some rubs, scratches, water rings and a cigar burn on the top.
I vacuumed miles of cob-webs and a 1/4″ thick layer of dust before even attempting to remove it from the back. The radio has a unique power transformer style, only GE used “bathtub” power transformers like this. Most are normally square with square cores…this one’s an oval. You can see the motor preset assembly and the pair of output tubes as well.
The chassis is enormous and has a lot going on.
Underneath, it looks like someone’s taken a crack at it in the ’80s or ’90s. There are a pair of orange drops, and a pair of modern electrolytic capacitors – and a few 1940s/1950s era replacements – but other than that it’s all original. There’s a decent amount of crumbling rubber wire that will need to be replaced, and one of the coils has a broken solder lug that I’ll have to fix, but it’s in shockingly good shape otherwise and should be easy to service. Not many things are buried.
The cabinet cleaned up very nicely after intensive scrubbing with cleaning wipes, Goop, and plain water and rags alternately. Following that, two applications of Howard’s. It brought out the shine on the finish while still leaving the patina around the corners, and blending the scratches in the original finish. I lightly sanded the rings on the top, but not all the way, and left the cigar burn – I didn’t want to remove all of the “character” in the cabinet.
The chassis doesn’t have any good mounting points, so I bit the bullet and ordered one from Steve Strong who makes custom radio chassis stands. They’re huge, high-quality, fully articulated and can support a lot of weight. Arrived some assembly required:
All assembled, it can rotate 360° including suspending the chassis upside down, locked in with the chassis retaining bolts that normally hold the radio into the cabinet.
And locked in ready to go:
Most of the coils in the radio test fine, with the exception of the output transformer which has one half of the push-pull primary open. That’s bad news, but fortunately 6L6 tubes are pretty commonly used today in guitar and hi-fi gear, so new-stock output transformers are easy to come by. The original was rated for 20W; the closest size available for the replacement is an Edcor 30W transformer. The new transformer might even improve the sound quality a bit – losses in transformers were one of the sources of poor fidelity in older radios (and even in modern hi-fi gear); the new transformer is flat from 20Hz-20KHz.
Edcor builds the transformers to order, so it won’t be here for another month or so, but I’ll be starting on the rest of the repairs before then. Stay tuned!
It’s tough to get data out of a phone.
It’s surprisingly difficult to get data out of my Android phone, the T-Mobile G2. Much more difficult than I expected it to be, in fact. I recorded a short (7-minute) video clip using the build-in camera to demonstrate a radio working for my client. I receive an error message warning me that I can’t upload videos “over 1GB in size”, which is news to me because the filesize is only around 150MB. My only option is to attach via USB and copy the files off from the filesystem – not the most intuitive process if you’re not technically inclined.
I like Android because it doesn’t tell me what to do the way some other phone platforms do, but even nearing the 3.0 milestone the entire thing just seems amateurish and hacked together. I can’t say whether these issues stem from the open-source philosophy of the platform, the fragmentation introduced by lack of control over carriers, whether it’s due to Google having grown too fast for their teams to be able to work cohesively together across their organization, or something else – but it doesn’t seem like we’re really making much progress in terms of the user experience even as we add more features.
Don’t Bother Buying a Verizon MiFi.
You’ll just be disappointed. Very, very disappointed.
My job responsibilities include managing a cloud of about 50 servers that host an enterprise SaaS application. Naturally, this requires that I be available to take emergency calls and deal with them from anywhere. I have a great, lightweight laptop that frequently follows me around – an HP EliteBook with an internal Verizon 3G card. Unfortunately, my company upgraded our Verizon service to 4G and replaced my internal aircard with a device that makes me hate every interaction I have with it.
The MiFi is an excellent concept. It’s a tiny Novatel wireless bridge – Verizon Wireless on one end, and WiFi 802.11b+g+n on the other. Dead simple, too. Turn it on, connect using the password written on the back of the unit, and browse the Internet at lightning fast speeds. And it is fast: Speedtest.net gave me 16Mb/s downstream and 2Mb/s upstream in the back of a moving bus on the highway. It’s a shame its ease of use and speed are overshadowed by the fact that actually taking advantage of its features is horrible.
The device is tiny. Too small, in fact, because there’s only enough room for the most pitiful of batteries which deliver around 2-3 hours of use on a brand new charge. I’d expect a device like this to last at least long as the devices pairing to it – my EliteBook has about 7 hours of battery life if I manage my power consumption carefully. The battery life is so short, in fact, it would not last for the duration of a trip from my apartment to the airport on mass transit and if I forget to charge it one day, it’ll be dead by the end of my next morning’s commute. I’m curious who they’re expecting to want to use the MiFi, unless they’re figuring you’ll leave it plugged in all the time – which has its own issues.
But isn’t the battery life a non-issue because of the included USB charging cable? You’d think so! Rational logic fails again with this device, however, as plugging the USB cable in causes it to enter a locked mode where it stops broadcasting its wireless. Thus, I have to make a choice that shouldn’t exist: I can either charge my device, or use my device. What if the battery is dead already? This could be an issue with the current in the USB plug, I’ll have to do some experimenting to be sure – but I’m fairly opposed to devices that need the high-current ports to work right in teh first place.
Tough luck. And don’t get me started about the fact that it tends to lock itself into 1xRTT at approximately dial-up speed, even though LTE is broadcast from the same tower, or that the fall-back process between LTE 4G and CDMA isn’t very graceful, can go up and down quickly in a short period of time, and causes the connection to drop out while reconnecting.
I’d recommend you save your money and just buy a USB dongle or an ExpressCard. Or take your dollars to a carrier with better hardware, but there might not be any better.
Managing Expectations in a Mobile World
I’d like to share some frustrations I’ve been having with my Android phone, the T-Mobile G2. I was a completely satisfied customer of the G1, which was released about 2.5 years ago – an eternity in mobile technology, but not really that different from the current iteration of devices in a significant way.
Mobile devices have reached a shocking level of compatibility and functionality. Paired with a suitable data plan, the modern smartphone can legitimately be compared to a computer. You can watch video from sites like Hulu, YouTube and Vimeo; capture, edit and share photos and videos to other mobile devices, computers or web services; create and edit office documents, access web pages, stream music, send e-mail, chat and connect over any of dozens of web services, manage your finances, find near-by points of interest, turn-by-turn navigation…..the list of computer-like things a mobile phone can do goes on and on.
Note I said computer-like things because, despite all the progress that’s been made, cell phones are still sorely lacking in actually being able to do most of the things I’ve listed quickly and easily. Cellular providers share some of the blame, which I’ll get to in a few moments. Cell phones have advanced well enough to where they can be judged on the same standard as a basic desktop computer – and are falling flat on their face as a result. Just being good “for a phone” isn’t enough any more when the end of the PC is approaching and marketing efforts are setting customers up for disappointment if they’re expecting a full-featured experience.
The G2 is about as unmodified of an Android build as you’re likely to find on a mass-production phone – and it’s a mess of usability issues, bad design, poorly thought out features and to top it off some of the limited potential it does have is being choked off by the cell phone companies. Take for instance Android ActiveSync, the application that connects Android phones to Microsoft Exchange servers. It frequently loses the ability to synchronize, forcing me to reboot the phone to restart sync. It doesn’t effectively sync subfolders, meaning that my “Alerts” folder nested inside my Inbox is never synced if Inbox is the active view. And occasionally it spontaneously forgets I ever attached an ActiveSync account, and instead of my e-mail in the morning I wake up to the Add Account wizard. That’s utterly unacceptable for a production device – but this happens not only on my Android device, but on multiple phones on different providers belonging to others.
Flash on the phone has been another area where phones have effectively fallen on their face. There are some technological reasons behind this failure, but the fact of the matter is, Flash that works just well enough to render the applet’s interface but not well enough to let you actually interact is completely useless. Flash is being sold to Android users as being able to unlock the “rest of the web”, but I can’t even manage to load the Pandora desktop SWF functionally.
And speaking of Pandora, we come to the role of cell phone providers in this whole mess. I live in a dense metro area, the 23rd largest city in the country. The area is blanketed with fast “4G” coverage measured in megabits per second. Pandora offers a mobile application for devices – with significantly reduced audio quality from the desktop application, which they blame on the cell phone providers:
Pandora on phones is limited by hardware and bandwidth. Many carriers have trouble streaming even the “normal” quality audio on phones (32kbps). The High quality is 64kbps.
Desktop normal quality is around 128kbps, and high quality is 192kbps. If providers really have trouble streaming audio in the same quality as we had on desktop computers in 1998 – 13 years ago – there is a serious infrastructure issue in our country. Net Neutrality might help with this somewhat, but most likely not.
There’s a long way to go before the “end of the PC” really arrives.
T-Mobile G2 Home Screen Won’t Rotate
I’m a fan of my new T-Mobile G2. I waited until it became close to free with contract, and that makes it even more satisfying, but it’s not without a few annoyances. One of the problems I’ve noticed is that the home screen on the G2 won’t rotate if the phone is shifted into horizontal orientation, even though most apps will rotate.
Home screen rotation is one feature that you can add by picking a third-party Android app launcher. There’s a rundown of the three leading contenders over at Lifehacker, but in my opinion LauncherPro is the simplest choice of the three.
I’ve been using it for a few days now and it’s very interesting. I like that my home screen will automatically rotate now as well – it makes the fact that the phone likes to shift into the wrong orientation very often slightly less annoying. I’ve hidden apps that I can’t uninstall but don’t want to have to see, either. I think I’m going to pay the $2.99 for the full version, it’s so impressive.
The reason I selected LauncherPro is that it looked the most interesting, and could be installed on my non-rooted phone. I’m exploring what my phone can do from the factory before I modify it, and I haven’t quite reached the limits. So, if you’re looking to make the home screen rotate…or just in general make it easier to launch apps, go with that one.
Thoughts on the T-Mobile G2
For the first time in my history of buying cell phones I decided not to pay the early adopter tax and just waited until the phone I wanted, the G2, became free with a contract extension. That happened this month, and I’ve had the phone in my hand since Monday. I’m definitely glad I waited, though, because if I’d paid $150+ for it I’d be quite disappointed.
Firstly, the notification light is hidden behind the touch button at the bottom center of the phone; the only indication you have a message is a barely-visible faint white glow that slowly pulses on and off. There is a multicolor LED up near the top of the phone, but as far as I can tell it only indicates when it’s charging. Supposedly this problem will be fixed with the 2.3 Gingerbread update, but I’m shocked.
Second, the accelerometer is touchy and likes to rotate the phone into horizontal orientation if I hold it at any angle that’s not perpendicular to the ground. Or, the homescreen will be in one orientation but applications I launch will be in rotated orientation. This is frustrating for obvious reasons.
Third, even though the G2 runs pretty much a stock Android build, Google has decided to include many applications I am not interested in having – and you can’t remove them. Finance and PhotoBucket both run as services on my phone, both auto-respawn when killed by a task manager, and both cannot be removed.
Finally, though, the most frustrating thing: the audio quality. Call quality is great, but listening to music is painful. My G1 had higher quality audio, I’m pretty sure. Pandora sounds tinny and distant even with high-quality streaming enabled (Pandora One) and full bars of HSPA+; it sounded much better on my G1 and sounds great on my stereo at home so I am inclined to believe the issue is with the phone itself. I have a nice pair of Sony noise-canceling headphones, but can’t tell the difference between them and the bundled mini-earbuds that came with the phone. That’s a problem.
I do like that the phone is very fast, has a lot of storage space and a standard headphone connector. I do like that I can give it up to a 32GB microSDXC card and load it up with media for when I ride the bus. I rather like the Swype input panel, in fact I use it more than the hard keyboard at this point, and the hard keyboard was a major selling point for me. But, based on these shortcomings I’ve outlined here, I can’t really recommend it to anyone else. I’ll probably keep it for a year, and go back to paying the early adopter tax on the next generation of phones when they come out.
Magic Eye Tube Spectrum Analyzer
French hobbyist Sylvain came up with a fascinating project using 8 Magic Eye tubes from old equipment to make an audio spectrum analyzer. I’ve worked with magic eye tubes quite a few times, they’re very fascinating. Originally precursors to CRTs, they’ve found a lot of use as level indicators in all kinds of equipment up through about the late 1960s.
He built a beautiful project case for them, too. Click through to his blog to see the build log and all photos!
Originally reported on Hack a Day.
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