Sunday, 4 February 2018

Pi 3 Network Attached Storage, Torrentbox, ADS-B server

One microcomputer connected to an external hard drive providing wireless access to data, looking after torrents, and supplying aircraft information - all at the same time.
Tutorial below is written for ordinary folks, in plain English, with as much spoonfeeding as possible, contains own purchases, product samples and affiliate links (disclaimer). All links open in new window, tap / click images for full screen, prices are given in dollars, more or less the same in euros.
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Update February 7, 2018: Added more information on components and removed unnecessary command - thanks for feedback!

What?


Complete system looks like this, not larger than your palm:



Raspberry Pi 3: microcomputer, does the heavy lifting.
Network Attached Storage: external hard drive connected to home wireless network, stores files, pictures, videos, accessible from a computer, smartphone or tablet on the same network. Some WiFi modems have an USB port for external drives, same end result. Personal data backup without cloud costs, anyone?
Torrentbox: share files with the world, also called peer-to-peer sharing.
ADS-B: get aircraft data for less than $10.
Do as much as you want, adding torrent capabilities or ADS-B is cream and cherry on the cake. Or the other way round, if already running an ADS-B station, more functions out of the same Pi 3 is just a few lines of code away.

How much?


Budget around $70 for a full Raspberry Pi 3 Kit, options for data storage below, a generic RTL-SDR dongle for ADS-B is yours for less than $10, but even the best bundles are less than $30.
Worth it? A ready-made 2TB Network attached storage is around $140; a full Pi 3 Kit and a 2TB external hard drive is about the same cash, but you can simply do more and end up with more equipment with a Pi 3 based setup.
Time required is less than one hour; mainly depends on Internet connection speed. Even if totally new to Raspberry Pi 3 / Linux, full operational capabilities can be reached in an evening by following this guide and simply copy-pasting commands.

Shopping list - Hardware


Amazon shopping note: equipment might be significantly cheaper or only available to a Prime member, subscription costs around $10 per month, can be cancelled after 30 days, do the math, saved $10 after subscription cost when bought two 64GB Sandisk Ultras versus normal Amazon price.
Raspberry Pi 3: required board only is around $37 but needs accessories to function, a microUSB card and reader, plus a power supply and Internet cable (officially called Ethernet cable) as minimum.
The whole nine yards in image below, pick what you need, bits n pieces discussed later on:



Newbie best overall choice, and the one I recommend is a ModMyPi Starter Kit for around $70 plus shipping, review here. I also bought a Vilros Raspberry Pi 3 Complete Starter Kit ($70 + shipping), which might come out cheaper if in the USA, excellent value with 32GB card, but no Ethernet cable.
Storage: reliability is number one, choice depends on how much data you got, over Terabyte levels my vote goes for Western Digital external drives and hard drives as not one failed in the last 25 years, thought some swear by Seagate.
If looking for volume, buying anew, a WD 4TB Elements Desktop Hard Drive for near $100 is enticing. If already own hard drives, a docking station is great, Inateck in image above also copies an entire volume with a push of a button and can accommodate either regular (3.5") or laptop (2.5") hard drives - was invaluable when switched over to SSD in my laptop, push in two drives, press copy, done.
"Portable" drives do not have external power, sucking power from host computer, a Pi 3 can't really handle that. Check product description or images whether drive got one or two holes on the side, if only one (= only data), not good.



Sidenote: Even a Pi 2 can handle a 320 GB portable drive pulling duty as a Torrentbox, but same Raspberry can't handle an added RTL-SDR receiver or a portable drive above 500 GB - simply not enough power coming from the Pi.
Want reliability, portability, versatility and speed? Flash drives are the best, but expensive in comparison, same money for less than 10% capacity versus a powered external hard drive. SanDisk Ultra Flair 64 GB USB 3.0 Flash Drive in image above, because 1) monster volume big drives are not supposed to spin for a few Gigabytes as decreases lifespan, and 2) thumb / flash drives are no hassle and incredibly versatile, portability means swapping between smart TV / phone / computer takes a few seconds if necessary. 
ADS-B receiver: All reasonable choices are below $30, get a Nooelec SMArt Bundle for $26 (review, Amazon) for ease of use form factor, warranty and quality. All other dongles require an USB extension cable because they're too wide, blocking nearby USB ports on a Raspberry.



Cheapest RTL-SDRs are generic dongles for less than $10, don't pay more. Any FlightAware Pro Stick (orange review, blue Pro review, Amazon) will be best value for money for performance (if available, hardcore nerds buy them up) with a homemade Coketenna. An rtl-sdr.com v.3 bundle is the most technologically advanced (review, Amazon) RTL-SDR receiver with an excellent antenna pack, good investment. More ADS-B receiver comparison here.
microSD cards: same type which go into smartphones / tablets, minimum 8 GB, Sandisk Ultras (red over silver) are double speed versus noname for 2-3 dollars more, half time staring at screen.
Ethernet cable: also called RJ45, connects Pi 3 to WiFi modem, two hand movements, two clicks, done. Costs a few dollars on Amazon depending on length, e.g. 20 feet for $5, or off the shelf in any supermarket. Yes, Pi 3 has wireless built-in, skip this part if have a monitor, keyboard, and HDMI cable, and want to fiddle around - an Ethernet cable is the easiest and most reliable choice.
Optional: powered USB hubs draw power from the wall socket, not from the Pi 3, and recommended if connecting portable drives or using more than one external hard drive.  Cheap ones without external power cost up to $10 (e.g. left one, one cable), a 7-port USB 3.0 (right one) with power is $30 (two cables, data and power).



Personal note re equipment: just buy the best you can afford, money is long forgotten when gear will still function years down the line.

Software


Tutorial below assumes you use a Windows 7 operating system like most visitors do, concept will be the same for the minority, tried installation steps with Android smartphone and tablets, works. I got no Mac so can't elaborate.
Download software below before starting workflow into one folder, you might have some of them already, my choices are below.
Raspbian: operating system for the Pi 3, start downloading Raspbian Stretch Desktop now.
Extracting files: 7-Zip for Windows, direct download link.
microSD card writer: Win32 DiskImager, green button top left, download starts in a few seconds.
Remote connection: Putty for Windows, direct download link, or search your app store for "SSH software" if on tablet / smartphone.
Network IP finder: Advanced IP Scanner for Windows, Fing for Android. Or search for "network analyser" in your app store.

What we gonna do


In short: install software, use those software to control a Raspberry Pi 3 remotely, adjust, be merry. If you can use a computer without a nurse's help you're more than capable. In case you wonder, the official Pi 3 installation steps are pretty much the same but with less detail.
Bit longer: write latest Raspbian to microSD card, add support to connect remotely, plug in external drive and microSD card, power on, update, enable user rights, add Samba so Windows can see Pi 3, add Transmission for torrents, add FlightAware for ADS-B, happy days.

How to use this guide without hassle


0) Download operating software for Pi 3 from here.
1) Install all necessary software, again: file extraction software, Win32Disk Imager, remote connection (Putty) and network analyser.
2) Once over the initial steps, open this guide and Putty window side by side, like this:



3) Made the guide with as little typing as possible using a mouse as well.
Copy-Paste: once used it you'll know what to do, but to be on the safe side: with mouse, highlight commands, that is text with space above and below in this guide, left click and hold to select text, then right click once, Copy from menu appearing, then left-click in Putty window, which makes it active, green square outline turns into green filled in square, then one right click with mouse to paste command copied, press Enter. This sounds complicated when reading it, do it twice, comes second nature then.
4) Look at keyboard, we gonna be using a working environment where you control Pi 3 with a keyboard, this is called command line environment.
On an English American keyboard, "Enter" means the big button in the middle, "Y" means the letter Y, PageUp and Page Down are buttons on the right side, text written on them, "arrows" mean, well, arrows, backslash is  \\ and forward slash is  // (left and right of a keyboard in row above space, which is the longest key, one at the bottom). Writing SHIFT+ means press and hold down the Shift button and press the letter after the plus, like asterix is ****, SHIFT+8. Word "delete" means the Delete key, above arrows, up movement with right hand, deletes symbol under green square, Backspace deletes symbol to left of green square.
Do not use keyboard on right for numbers, use numbers above letters, funny things can happen in a Linux editor. Sign of """" is SHIFT+2, anything else you need on a weird French / whatever keyboard please look down, will be there.
5) Pay attention. Pi 3 will do exactly what you tell it to do, mistakenly type one more dot such as 192.168.0..3, or writing Pi instead of pi and it's head-scratching time.

Getting the Pi 3 up and running


Download Raspberry Pi 3 operating system if not already done so, go for the torrent if you got a Torrent client as it's faster, get the following file:



Right-click, extract with 7-ZIP:



Resulting file needs to be written to microSD card, so insert microSD card with adapter into computer, then start Win32DiskImager.



Check name of drive in file explorer, then select Raspbian image (file you've just extracted) in Win32DiskImager, double-check correct device name, then click Write, Yes, Yes:



Optional and recommended for new drives: in the meantime, if just bought a flash/external hard drive, plug it in, will show up in File Explorer, format it with Quick format, type shall be NTFS (Pi 3 / smartphone / tablet / smart TV will instantly see it).



Back to installing Pi 3: when card writing successfull, DO NOT remove the micro SD card.



In file explorer, on the microSD card, create a text document called ssh:


Note: if Windows moans that disk is write-protected, slide the little switch (top left) in the other direction on the microSD card adapter.

Safely Remove Hardware, green icon next to clock, usually bottom right of screen:



Insert microSD card into Pi 3, plug in Ethernet cable (make sure other end is securely into home WiFi modem, hear a click), external hard drive, RTL-SDR dongle:


Sidenote: blue USB port in image above is for an external hard drive to get NAS without all this programming, but that's limited functionality compared to a Pi 3 setup with Torrentbox and ADS-B.
Power on Raspberry, wait two minutes, get a network analyser out, Pi 3 will show up on your local / home network, Advanced IP Scanner on Windows:


Fing on Android:



Write down this IP address, will be required later on, or write it on Pi, makes identification easier. In this tutorial, I'll use 192.168.0.3 just like in image above.
Start up Putty, enter IP address of Pi, press Enter:



Say Yes to Warning message:



Enter pi as login name, press Enter, and raspberry as password, press Enter - password will not show up when you type, that's normal:



Success, you're remotely connected to a Raspberry Pi 3! Well done, anything from now on is just copy-paste and some typing.
Geek notes: process above is exactly the same as if installing any .img based operating system, called "flashing" in Linux lingo to confuse new users. Safely Removing Hardware is well advised. Any smartphone/tablet based network analyser will be faster to install and get Pi 3's address than a Windows counterpart, once known, tends to stay the same.

NAS / Network Attached Storage commands


Commands do not start with bold letter such as this line and always in separate line to make it easier what you need to easily copy-paste.

Start with:

sudo apt-get update -y && sudo apt-get upgrade -y && sudo apt-get install ntfs-3g -y

Pi 3 works away for a few minutes, like 5 or 10 depending on Internet connection speed, white text scrolls on black screen:



That’s normal, wait patiently, all in order - this is the moment you'll start feeling "I got this, yeah!"
Next:

sudo blkid

Check name of external drive, bottom white line in image below:



Can be sda, sda1, sd2, starts with sd, adjust commands below accordingly, sda and sda1 is the most common; I use sda in commands below so you only have to enter the number 1 or 2 if sda1 or sda2 etc. Again, use numbers above letters on keyboard, not the numerical keypad on the right.
Directory name will be "changethis" in this tutorial, or whatever you fancy, must be same later on, so don’t choose KimsExternalLittlePonyFlashDrive unless fond of typing.
Again, external drive is named "changethis" for simplicity, if you see changethis or sda in commands below please adjust: copy-paste command, then navigate to part with left or right arrows, delete with Delete key, enter numbers with numbers above keyboard.

Copy-paste the following:

sudo mkdir /changethis && sudo chown -R pi:pi /changethis && sudo chmod -R 775 /changethis && sudo umount /dev/sda && sudo mount -o uid=pi,gid=pi /dev/sda /changethis

I always get the message that the disk contains an unclean file system, Pi 3 takes care of it in less than 30 seconds.



Check whether the external drive is mounted (it will be) and if so, into what directory:

df -h

Nearly there, external hard drive is mounted to directory, see bottom white line in image below:



Automatically mount the disk upon restart:

sudo nano /etc/fstab

Black on white text editor with lines comes up, left click in Putty window, then use down arrow on keyboard to go to bottom.
Copy-paste the following, repeat, adjust sda and changethis as necessary, 

/dev/sda /changethis ntfs rw,nosuid,nodev,default_permissions 0 0

CTRL+X,“Y”, Enter, back to black screen with green.
Happy days, external drive is mounted successfully!
Geek notes: Boolean operators && used in commands above to simplify steps; -y to prevent pressing "Y" and Enter unnecessarily. If installing more than one hard drives, firing up a text editor and replacing sda with actual reference and changethis with desired name means less typing. Yepp, that matters with multiple drives, copy-pasting this paragraph into a text editor, then Replace command in Word saves lot of time.

SAMBA


That’s for Windows to see the Pi 3 and to talk to each other.
Start with:

sudo apt-get install samba samba-common-bin -y && sudo chown -R pi:pi /changethis && sudo nano /etc/samba/smb.conf

Pi 3 works away for a few minutes, then:
Text editor opens up, lots of text on screen, repeatedly press Page Down key to go to bottom, copy-paste the following there:

[Changethis]
comment = changethis
browseable = yes
path = /changethis
writeable = Yes
create mask = 0777
directory mask = 0777
browseable = Yes
public = yes

Screenshot:



CTRL+X, “Y”, Enter, back to green on black, next command:

sudo /etc/init.d/samba restart

Screenshot after command:



Part Two complete, Pi 3 shows up in Windows under Network:



Geek notes: [changethis] will be name on Windows of external hard drive; if using more than one drive, adjust this name to represent the actual drive, see notes later.
path = /changethis refers to drive mounting location, if different from /changethis with two or more drives, adjust.

Transmission



Torrenting server software, same as uTorrent or any other torrent client. It's a service to the community to share the Pi 3 operating system if you got an Internet-connected Raspberry.

Install:

sudo apt-get install transmission-daemon transmission-cli -y && sudo service transmission-daemon stop && sudo mkdir -p /etc/systemd/system/transmission-daemon.service.d && sudo nano /etc/systemd/system/transmission-daemon.service.d/local.conf

Text editor opens up, blank black screen, copy-paste the following:

[Service]
ExecStart=
ExecStart=/usr/bin/transmission-daemon -f --log-error -g /etc/transmission-daemon

Ctrl+X,” Y” and Enter to go back to command prompt, then:

sudo systemctl daemon-reload && sudo service transmission-daemon stop && sudo usermod -aG pi debian-transmission && sudo usermod -aG debian-transmission pi && sudo chmod 775 /etc/transmission-daemon/settings.json

Then:

sudo service transmission-daemon stop

Then:

sudo nano /etc/transmission-daemon/settings.json


Text editor opens up instantly with blue (settings name), green (what you change) and pink text (also changeable, inbetween quotation marks, that’s the """" symbol, Shift+2 on an English keyboard). The star **** is Shift+8 if you need it.
Text is in alphabetical order, if familiar with torrenting, you’ll know what’s seeding so you can adjust accordingly, if not, leave everything as it is and only change the following, move cursor with arrows:
“download-dir” change to “/changethis” (or whatever name / mount point you gave to the external drive).
“rpc-whitelist-enabled”: change to false, text turns green, any computer can connect to Pi 3.
"umask": change from 18 to 002, use numbers above letters on keyboard.
Finished unless you wanna do more changes, but only if you have a remote clue what’s a seed queue.
Then the usual by now: Ctrl+X, “Y” and Enter, then:

sudo service transmission-daemon restart

Enter the Pi’s address in a browser on a Windows, followed by :9091, like 192.168.0.3:9091, get Transmission's web interface.
Put mouse over icons and read what they mean, load a torrent from the folder icon top left corner of screen: download, then add the Raspbian torrent from official webpage, Transmission browser will look like this:


More info on Transmission on the official page.
Geek notes: no authentication required to access Pi 3, so no hassle entering passwords users are likely to forget. Stopping transmission before editing settings is absolutely necessary, therefore added separate lines, then restart service.

Add ADS-B capability


Steps exactly as per the official FlightAware page, parts of my guide for setting up an ADS-B station should be relevant for new users.
Combining all steps into one command to save back-and forth between guide and Putty:

sudo wget http://flightaware.com/adsb/piaware/files/packages/pool/piaware/p/piaware-support/piaware-repository_3.5.3_all.deb && sudo dpkg -i piaware-repository_3.5.3_all.deb && sudo apt-get update -y && sudo apt-get install piaware -y && sudo piaware-config allow-auto-updates yes && sudo piaware-config allow-manual-updates yes && sudo apt-get install dump1090-fa -y

It takes minutes for FlightAware to recognize you added a new station, register in that time, go to Claim a station, see that all is well:


Station will show up in your control panel in about 15 minutes, on any connected device, go to Pi 3 address and :8080, such as 192.168.0.3:8080 to see aircraft:



Once done, it's a good idea to feed other suppliers, tutorial here.

Performance


Ran installation steps and commands above over, over and over again, tested on a Raspberry Pi 2 and four Pi 3s, with 5 microSD cards and four external drives featured in this tutorial, worked every time.
Social: great when friends or relatives come over, can share my files and videos after providing WiFi password, and they can also upload their files. On Android, File Manager works well for file transfer, VLC Media Player sees network drive and can play video of my dog attacking a tree stump. Simply having a network drive where all family / buddies can upload files is priceless, easier than searching for cables.
Watching videos: 720p HD videos from Pi 3 external drive can be played without lagging over WiFi on a computer, smartphone and tablet.
Torrenting: seeded 20 torrents worth 58 GB whilst watching a 720p home video without lagging.
ADS-B: performance will depend on receiver and antenna plus a host of other factors, didn't seem to really affect other operations / services.
Not all at the same time: disk use is the bottleneck, e.g. backing up files from a smartphone to external Pi 3 drive and trying to add 10 torrents via Transmission interface = browser becomes unresponsive, if watching a video it will start to freeze up. Once Pi 3 catches up, you can do one thing at a time.

Renaming drive


Mounting point names (which folder Pi 3 thinks is the hard drive, reason I chose changethis as variable) should be preferably adjusted for sanity, Samba name [changethis] better represent capacity and/or any easy to remember identification aid.
Renaming a hard drive for easier identification can be done by stopping samba service with:

sudo /etc/init.d/samba stop

Then edit the bottom of smb.conf file (press Page Down repeatedly) and change names:

sudo nano /etc/samba/smb.conf

Save your work: CTRL+X, Y, Enter, then restart service:

sudo /etc/init.d/samba restart

Screenshot:



This will only change how Windows recognizes the external drive, won't change the access path of /changethis.


Adding more hard drives


Pi 3 can handle more than one external drive as long as they do not draw too much power; consequently I added one more 64GB Flash Drive:



Just plug drive into the Pi 3, no need to power off, then:

df -h

Second drive is seen by the Pi 3 instantly:



However, I'm not happy with the access path (letters and numbers next to 47%), so repeat steps above by adjusting sda to sdb1 and changethis to whatever you want, I chose top:


Change Samba name as well, 3 minutes later 2nd drive shows up as a Network Attached Storage in Windows:


Or on Android (with File Manager app):



Continue adding external drives if you wish, but remember, Pi 3 can't really handle portable drives so use a powered hub, or a powered external drive.

Read more to know why and how commands work


Indebted and used information from the following websites, full credit:
Decreasing GPU memory for headless server setup: https://haydenjames.io/raspberry-pi-3-overclock/
Personal final note: freely admit to knowing nothing in comparison to some readers when it comes to Linux / Pi 3 permission levels, user authentication, and many more I'm probably unaware of. Simply put, I wanted a NAS / Torrentbox / ADS-B server, and existing guides were either outdated, way too complicated for new users, did not contain sufficient information or required endless attention. I'd be delighted if Linux or Pi 3 gurus wrote in how to make this tutorial better for the end user, nameless or full credit given as always.
Wanna help out if you know more? Comment below.

Saturday, 23 December 2017

Top 5 of Software Defined Radio

Cause I want peace of mind, going away for 2 weeks of incommunicado, here's what I'll carry:




From top left:

Nooelec Mini 2+ Al: backup, sheer performance, still the best RTL-SDR dongle when aim is hearing a signal.
Nooelec SMArt: backup, for SMA connector, easy for USB port, will work.
rtl-sdr.com v.3: same as SMArt, backup.
SDRPlay RSP1A: secondary, currently the best SDR below $100, better than RSP2 above three digit MHz numbers.
SDRPlay RSP2: primary SDR, wouldn't carry others but I got a choice.
Cables: for SDRPlay and dongles, ferrites are compulsory.
Antenna: SMA connector, telescopic, can overcome shortcomings re length or ground plane, but SMA is a must.

Merry Christmas and festivities to you all, heartfelt thanks to more than 500,000 readers this year, and to supporting manufacturers, commenters, haters, naysayers, all of you helped me in ways you cannot imagine.

I'll be back sometime in 2018.

Akos out.

Wednesday, 20 December 2017

Comparison: Generic RTL-SDR R820T2 vs Nooelec Mini 2


Generic or branded? $8 or $21? Observations after Nooelec sent a brand-new Mini 2 (manufacturer, Amazon) for review (many thanks, disclaimer) and bought a fresh R820T2 off eBay. Identical receiver specs on paper, but are they really the same?



Interchangeable cases:



PCBs look quite similar, click on image for full screen view:



Upon closer inspection, component mounting on PCB, sideview:

Supplied mounts and coax cables: same diameter, same holding power of magnet, discover the difference between coax cables:



Supplied antennas: Mini 2 has more than twice the length and adjustable.



Why does it matter? Signals are received by the antenna, and with a larger / longer antenna you got a fleeting chance of listening to fun action bands below 200 MHz, e.g. airband with generic and silver telescopic, higher peak in the image better (able to understand voice):

Sidenote: receive performance matters primarily on antenna used, location, line of sight, and a host other factors, simply put, the Mini 2 with the supplied antenna will provide more listening pleasure.
Performance with external antenna: indistinguishable on an external discone by ear, tested on ADS-B and totals within three percent. Mini 2 has a less noisy waterfall image:


Try that again:


Don't ask why, only swapped dongles, both were fully warmed up.
Warranty: Mini 2 6 months, generics comes with 30 or 60-day warranty:


Support: close to nonexistent with a generic, Nooelec seems to be staffed with people who actually use what they sell, therefore can intelligently answer questions.
Reliability: Bought a Nooelec dongle more than four and a half years ago after generics failed, and that dongle is still ticking without any hiccups:



Featured in many old posts of yours truly (e.g. Reducing electrical noise) so it wasn't pampered, in fact, I bought my first Ham-It-Up after seeing that a dongle with Nooelec written on them won't let me down.

Comment and answer:

Came up elsewhere as well:
"What was the results of tests of both units with the same antenna mounted outside?"
Two eggs, same PCB, Nooelec is clearer, but won't matter at the $8 level. Difference is antenna, warranty, build quality, receive performance will be hard to see or impossible to hear for sighted people.

Conclusion


This or that? Truly believe that a generic RTL-SDR R820T2 is the best value for money in the radio world, and - be realistic - with bills looming on the horizon, $8 is less painful than $21. But with limitations: shoddy antenna, questionable build quality and no long-term support. Feel free to read up how to do a few mods for better performance if you understand the "DIY" moniker.
Which one would I buy? Reliability, warranty and performance are the keywords for me, so I'd go for the Mini 2, better still, spend that extra few bucks and get a Nooelec SMArt or rt-sdr.com v.3.

Sunday, 17 December 2017

Ode to SDRplay RSP2

Unadulterated and highly personal review follows of a product I love. Been writing this post for many months, in fact, over a year, adding and subtracting, cracking an RSP2 is not possible, like an onion, deep into the rabbit hole, then some.
Conclusion: get Visa or Mastercard out, be happy. RSP2 is the beginning, the end, the ultimate Software Defined Radio.



Got my RSP2 before 2016 Christmas as a review sample, been using since as often as I could.
Normally, I do reviews with lots of images as a rule, but rules are to be broken, and this is not a review. Do a review of your wife when cooking, who cares when the end result is a nice dinner?
SDRplay introduced their first receiver, now called RSP1, nearly two years ago. Good receive performance, combined with all-in-one form factor, and integration with one of the best front-end software made it a popular choice.
Two years is a long time for a software defined radio (SDR), therefore a facelift was in order.
Price had to remain below 200 dollars and the new product, unsurprisingly called RSP2, had to work with existing software, so the core remained the same 12-bit tuner. Pretty much everything else has changed: most of the shortcomings I mentioned in my previous review has been improved, then SDRplay added more features. Then more.
Then head of finance showed up, inquiring how SDRplay will make a profit on the RSP2, was tied to a chair and made to listen to "All I Want for Christmas" whilst engineers went back to work:
- Improved case with RF screening,
- Three antenna ports, one with bias-T, one dedicated for sub-30 MHz,
- FM and MW filters,
- software-adjustable low noise amplifier,
- clock synchronisation,
- and so on, read the official Data Sheet here.
If you don't know what any or all of the above means, be rest assured that the RSP2 is one of the latest, most technologically advanced, and most practical Software Defined Radio receiver.
SDRplay sent a production unit RSP2 for testing shortly after the official announcement - thank you. As always, what you read here is my honest opinion.
I'd like to make one thing crystal clear before we start: this is not a lab review. I don't live in a lab. rtl-sdr.com has already done one and featured the RSP2 several times, therefore I listened to the RSP1 and the RSP2, alongside the best the RTL-SDR scene and traditional solutions has to offer, in two countries at multiple locations, at sea and on land, with various antennas for over a year.
Written down what I heard at the field and at home, then interspersed notes with comparative technical details and personal observations.
Again, do not read what follows if you value your time, if thinking of buying one and need justification, stop thinking, buy one if you can afford it

Pricing and availability


Less than, or close to 200 dollars' equivalent local currency, depending on where you live. To Ireland, an RSP2 delivered costs a few bobs below 200 euros. That's birthday and Christmas put together money range.
200 dollars seems a large wad of cash for a small plastic box if you're unfamiliar with radio equipment prices: a handheld communications receiver, or a top portable world-band radio costs about the same.

Who is it for


- people thinking of upgrading from RTL-SDR based dongles,
- existing RSP1 users,
- newbies with a gold credit card wanting a one-time purchase,
- amateur radio ops looking into SDRs and yearning for a good solution.

Unboxing


Plastic box with printed instructions inside envelope, protective red caps on SMA ports. Slightly larger than a pack of cigarettes, small and light enough to put into a pocket, won't pull your pants down.



New case material and texture, RSP1's coffee stirrer plastic quality is gone, replaced by a textured matte black finish. Feels in the hand like an industrial handheld transceiver, better than a Baofeng, equals an Icom, still not Motorola level, but a huge improvement over the RSP1.
Minor changes on the case, antenna ports moved up, so reassembly is easier, two new MCX female ports for clock in and out - these are NOT antenna ports.
Indentation on top, slightly heavier, external changes help distinguishing it from RSP1 in the dark by feel alone.

Software


Comes with own and free native software, called SDRuno, offical link here, which also works with RTL-SDR dongles, so you can familiarize yourself if you got an ordinary dongle, or read my guide by clicking on this link.
A lot of visual real estate will be required to enjoy a maximum of 10 MHz visible span on screen. 10,000 kHz worth of instantaneous spectrum monitoring is cool, but you'll need more than a small laptop screen to actually identify a transmission. Multiple screens, as large, with as much resolution as financially possible is required to fully enjoy 10.66 MSPS.
SDRuno (officially) supports multiple 4K displays and rescaling is click-and-pull, so if you've just robbed a bank, or won the lottery, you can enjoy breathtaking resolution on three 4K LCD TVs.
I only got an old laptop which costs around $400 new, and it managed to spread 10 MSPS across two car boot sale monitors, but with a lot of fan noise. Peace and quiet returned at 5 MSPS, which is more than enough for my purposes.

No antennas nor accessories


Great as a doorstop, albeit a quite expensive one.
Please, send at least a rudimentary coax and any kind of antenna, the general public needs a solution right out from the box to hear signals.

Bias-T


A.k.a sending power down the coax cable to power an antenna-mounted preamp. As explained earlier, LNAs are good for you, not only to overcome coax loss, but to lower overall system noise figure.
RSP2 worked with LNA4ALL, novakx5 LNA, and Outernet's preamp straight away.

Built-in adjustable gain Low Noise Amplifier


Software-selectable, as in there's a button you click in SDRuno, and LNA turns on for selected antenna port.

Three antenna ports


Finally. By my estimate, 100% of enthusiasts use more than one antenna, and screwing on a frequency-specific antenna was a chore with the RSP1. Not anymore: I can keep the discone on Antenna port A for "let's browse around", power a mast-mounted LNA for airband (substitute with 2m / 70cm / whatever you fancy), and use a random wire for shortwave.
A step in the right direction, but not enough. Instead of, or in addition to clock in and out ports, I'd love to see two or three more antenna ports. 

Intermittent personal observation


RSP2 is demanding for an enthusiast. I ride motorbikes, and know my goaround moped gets me there, but by now, I realised the RSP2 is a purebred superbike. Antennas matter a lot, just like throttle control, for weak signals, the difference between a random wire and band-specific dipole was huge in an electrically quiet environment.
In a city, a T2FD is hard to beat, and the RSP shined with it. A 200-horsepower machine needs warm weather, slick tyres and a good rider for fast lap times, just like the RSP2 needs middle of nowhere, a frequency-specific antenna and familiarity with SDRuno.
Make no mistake, RSP2 does the job with a makeshift antenna, riding straight on a highway is easy. SMA connector takes center conductor from coax, so I could get really good performance during a recent plane-spotting session when I left the mag mount at home.
Turn left for the twisty bits and depths of last-degree performance is there to explore.

HF port


Green yoke supplied with RSP2, officially called I have no clue, neither my electrician trade shop when I showed them what I want, couldn't get a replacement. This plugs into the side of RSP2, meant for sub-30 MHz signals.



Update 22/12/2017: search Amazon.com for "5.08mm 3 Way PCB Mount Screw Terminal Block", 10 dollars plus shipping:


Indebted to commenter Ross Bennett, that's what community is all about :-) Many thanks again.

TCXO: Entered frequency will be tuned frequency, hasn't been an issue with RSP1, but SDRplay added the feature anyway.

Sensitivity


That means how well a receiver can receive signals. The RSP2 is very sensitive.
Very sensitive. I write this down again, because if you're used to lesser equipment, you will just stare, shaking your head in disbelief. Feel free to read eHam reviews (4.7 out of 5 stars) or Ham Radio Science's post.
Writing about comparative performance versus this or that is moot, as reception is down to 1) antenna, then 2) location, and those two variables will not be the same between readers. Whenever I need to listen to a signal I just reach for the RSP2.

An enjoyable personal journey


I soldered my first receiver with my Dad when I was 6. Three decades later, the RSP2 gives a push. A push to perfect antennas, a shove in the right direction to optimise noise reduction in my home, a mental kick to drive bumpy roads to a hilltop with less man-made noise to catch a signal. Or just for the fun of it, and that, my dear reader, is the biggest feature of this black box.
SDRplay RSP2 is the devil on your shoulder. Whispering in your ear, take me out of a city, give me a good antenna, travel with me to the end of the world, and I will golden the very moment when you and me be at the right place at the right time.

At sea


Took the RSP2 for a spin on the West coast of Ireland during a recent mobilisation, had no issues. X-band and S-band radar didn't seem to affect performance, telescopic antenna with SMA worked well, shortwave was easy with a piece of wire. Couldn't do more due to 6 on 6 off watches, RSP2 worked without a hiccup, wasn't affected by violent vessel movement, unlike I was.

FM filtering


Works nicely. Push a button, FM band wiped out, interference gone.
Easy, as it should be.

Shortwave listening


The RSP2 with SDRuno is a shortwave listener's wishlist coming true.
I had a Tecsun PL-680 along (please refrain from indulging in the portable vs SDR debate for a moment), which is highly recommended by SWLing.com and costs the same.
Audio quality was nowhere near what I could get with the RSP2, the two receivers are not even on the same page.

Living with it


Only had the RSP2 for a while, went to remote locations, without electronic noise to assess HF performance, to the top of nearby mountains to see how far I can hear, and the impression remained the same.
Practicality rules. Magnetic mount on top of the car, with airband antenna, wires leading out from back window for HF. I had a v.3 and a SMArt, plus a Ham It Up representing RTL-SDRs, a Tecsun PL-680 demonstrating what a same-price portable worldband radio can do, and me old Icom IC-R5 as backup.
SDRplay RSP2 never left me wanting.

Personal lifersaver


This is the part you won't care about.
Walked down the slope, to the top of a nearby mountain, set up shop with antennas out the car window, laptop and RSP2 on the back seat as I wanted to get spine-shaking rush to the head of hearing a signal, a small joy, something I was looking forward to after 10 years of a progressively deteriorating relationship, loneliness, depression, "I feel so alone", into the sea, crawled out because I had something to look forward to.

 What to do with an old RSP1?


Give it to someone who needs it, like local schools, ham club, or anyone who could use it. SDRplay sent me an RSP1 for testing aeons ago, and Jon agreed to my proposal, so I have an RSP1 for education purposes. Get in touch with SDRPlay if you live in Ireland, but please only do so if you'll use it for the common good.
This approach is one more reason to choose SDRplay. Kudos to Jon.

Nice company to deal with


Questions to support got answered quickly (support@sdrplay.com), and SDRplay is working with other front-end software such as SDRConsole. And remember, these are the people who made a previously expensive software available for free to RTL-SDR users, then added full 2.4 MSPS support.

Versus RTL-SDRs


To assemble something similar, you'd need:
- dongle with TCXO for $25, 
- one more dongles to get two more antenna ports, add $25 each,
- upconverter for $50,
- preamp for $25,
- adapters to connect all above together, $10,
- FM filter for $15,
- and so on.
More money at the end of the day, just like any consumer product in parts costs an arm and both kidneys at the till if you want to go cheapskate and save money.
Regular readers know that I love RTL-SDRs, but had to grudgingly admit that the RSP1 was a hyperspace jump, and the RSP2 with added features is, despite the seemingly high price, is a realistic alternative if you want and can use its features.
For strong local signals, an RTL-SDR dongle will get the job done for significantly less.
For weak signals, the RSP2 is better than any RTL-SDR based setup.
Mindset matters, like when I was 17, in a testosterone-induced stupor spent my savings on an air filter, bigger rims and the customary ironing board on the back. Piece by piece, and yes, cleaning and detailed polishing will make any car faster.
Fact is, I must admit with a diminishingly balder head, that extra oomph comes from displacement, and this is the point when I have mention the 12-bit nature of any SDRPlay, if you still follow.
Common RTL-SDR dongles are 8-bit, and 12-bit is more, just like a Corvette is more than a Camry.

Versus AirSpy platform


I don't know. I don't have an AirSpy, because I didn't invest in one, despite reviews praising excellent performance, for the following reasons:
1. Software.
2. Two boxes.
3. Costs more.
SDRplays are just one box, which does it all on an old laptop. With HF port on the RSP2, I need an USB cable, a telescopic antenna and a length of wire to get signals locally and from around the globe. Anywhere.
The AirSpy vs SDRplay war raging online is akin to tea or coffee, or whether you should mix chocolate into porridge or just sprinkle on top argument.
Pathetic, really, as both are great receivers, both are excellent value for money - come on guys, let the other camp flourish.
Be merry that we got choices.

Before you buy one


I'd strongly suggest to order a premium dongle (Nooelec SMArt or rtl-sdr.com v.3 or SMArTee XTR bundle) kit for the supplied antennas, and think of dongle as a bonus. Connectors and antennas are compatible and well worth the price alone, receivers are great.
An USB to USB-B cable will be also necessary, try to get one with ferrites on both ends.

Summary

The SDRplay RSP2 is the best affordable all-in-one software defined radio receiver.
I can't think of a better solution if you have $200.
RTL-SDR dongles are near, traditional portables have no chance. When you add factors together, the RSP2 always comes out a winner. If you had to pay a thousand dollars, the RSP2 would still win.
More antenna ports: at least four for VHF and UHF and four for HF. I'd love to select frequency-specific antennas for a job with one click. Speaking of, I want editable names for ports in SDRuno, so I can know which port is the discone and which one is the airband.
I want to order green adapters, so I could set up band-specific antennas for mobile operation, a ferrited data cable should be compulsory, and if a company can make a receiver, why I can't order antennas to go with it?
Nothing beats the RSP2 for value for money. Or personal growth. Or what's out there. This little small box offers so much more than words can convey, therefore I can only come to one conclusion after more than a year's use: buy as many as you can afford.