We’ve looked at the WROOM-DA module before. It’s an ESP32 with two antennas, and [Andreas Spiess] says it is the ugliest ESP32 he’s ever seen. But beauty is only skin deep, after all. Did [Andreas] find beauty in the twin antennas? Watch the video below and see for yourself.
According to the block diagram, the twin antennas are not used simultaneously but offer diversity one at a time. There is also
8GB 8 MB of flash, double the amount on traditional WROOM modules. Mounting the device was a bit difficult since most ESP32 carrier boards will block some portion of the antenna array.
Continue reading “ESP32: Is Two Better Than One?”
We’ve only started to tap into the potential of the brand new Pi Zero 2. Having finally received his board, [Brian Dorey] shows us how to boost your Pi’s WiFi, the hacker way. Inline with the onboard WiFi antenna can be found a u.FL footprint, and you just know that someone had to add an external antenna. This is where [Brian] comes in, with a photo-rich writeup and video tutorial, embedded below, that will have you modify your own Zero in no time. His measurements show seeing fourteen networks available in a spot where he’d only see four before, and the RSSI levels reported have improved by 5 dB -10 dB, big when it comes to getting a further or more stable connection.
With old laptops being a decent source of WiFi antennas, you only need to procure a u.FL connector and practice soldering a bit before you take this on! The hardest part of such a project tends to be not accidentally putting any solder on the u.FL connector’s metal can – and [Brian] mostly succeeds in that! He shows how to disconnect the external antenna to avoid signal reflections and the like, and, of course, you will be expected to never power your Pi Zero on without an attached antenna afterwards, lest you have your transmitter become fatally confused by the mismatch of hardware-defined impedance expectations. A Pi Zero isn’t the only place where you’ll encounter footprints for connectors you can add, and arguably, that’s your duty as a hacker – modifying the things you work with in a way that adds functionality. Don’t forget to share how you did it!
This trick should be pretty helpful if you’re ever to put your new Pi Zero in a full-metal enclosure. Curious about the Raspberry Pi antenna’s inner workings? We’ve covered them before! If you’d like to see some previous Raspberry Pi mods, here’s one for the Pi 3, and here’s one for the original Zero W – from [Brian], too!
Continue reading “New Pi Zero Gains Unapproved Antennas Yet Again”
Do you remember the early days of consumer wireless networking, a time of open access points with default SSIDs, manufacturer default passwords, Pringle can antennas, and wardriving? Fortunately out-of-the-box device security has moved on in the last couple of decades, but there was a time when most WiFi networks were an open book to any passer-by with a WiFi-equipped laptop or PDA.
The more sophisticated wardrivers used directional antennas, the simplest of which was the abovementioned Pringle can, in which the snack container was repurposed as a resonant horn antenna with a single radiator mounted on an N socket poking through its side. If you were more sophisticated you might have used a Yagi array (a higher-frequency version of the antenna you would use to receive TV signals). But these were high-precision items that were expensive, or rather tricky to build if you made one yourself.
In recent years the price of commercial WiFi Yagi arrays has dropped, and they have become a common sight used for stretching WiFi range. [TacticalNinja] has other ideas, and has used a particularly long one paired with a high-power WiFi card and amplifier as a wardriver’s kit par excellence, complete with a sniper’s ‘scope for aiming.
The antenna was a cheap Chinese item, which arrived with very poor performance indeed. It turned out that its driven element was misaligned and shorted by a too-long screw, and its cable was rather long with a suspect balun. Modifying it for element alignment and a balun-less short feeder improved its performance no end. He quotes the figures for his set-up as 4000mW of RF output power into a 25dBi Yagi, or 61dBm effective radiated power. This equates to the definitely-illegal equivalent of an over 1250W point source, which sounds very impressive but somehow we doubt that the quoted figures will be achieved in reality. Claimed manufacturer antenna gain figures are rarely trustworthy.
This is something of an exercise in how much you can push into a WiFi antenna, and his comparison with a rifle is very apt. Imagine it as the equivalent of an AR-15 modified with every bell and whistle the gun store can sell its owner, it may look impressively tricked-out but does it shoot any better than the stock rifle in the hands of an expert? As any radio amateur will tell you: a contact can only be made if communication can be heard in both directions, and we’re left wondering whether some of that extra power is wasted as even with the Yagi the WiFi receiver will be unlikely to hear the reply from a network responding at great distance using the stock legal antenna and power. Still, it does have an air of wardriver chic about it, and we’re certain it has the potential for a lot of long-distance WiFi fun within its receiving range.
This isn’t the first wardriving rifle we’ve featured, but unlike this one you could probably carry it past a policeman without attracting attention.
Many Ham Radio operators in the United States participate in Field Day. This is an annual exercise where radio operators are encouraged to set up stations in conditions that might occur after a natural disaster. Usually, this means taking over some park or camp site, bringing generators, portable equipment, and making it all work for the weekend before you tear it back down.
It isn’t much of a Field Day without electricity. That’s why most stations use a generator, solar cells, or even batteries. Today, though, you probably need an Internet-connected computer to do logging and other features. [HamRadioConcepts] has a video (see below) that shows how they grabbed Internet from a distance for their Field Day site.
Continue reading “Ham Radio WiFi”
Antennas come in all shapes and sizes, and which one is best depends wholly on what you are doing with it. A very popular choice for sending video from drones is the cloverleaf antenna. It is circularly polarized which is an advantage when you have a moving vehicle. It also reduces multipath interference.
A cloverleaf contains three closed loops spaced at different angles. The antenna works well for transmitting but isn’t ideal for receiving. It is also difficult to tune after building it. However, for the right job, it is a good performer. [Vitalii Tereshchuk] shows how he made a cloverleaf antenna that fits a WiFi router.
Continue reading “A Lucky Antenna”