"why is everyone staring at us"
[glance back at where we were sitting]
"oh right"


since this is, for whatever reason, the one antennacane post that blew up, here's a better photo of the instrument that you probably missed before

and, while we're here, FAQ:
- It's a Yagi-Uda antenna for 2.4 GHz wifi with a gain of about 16-17 dBi across the band (center is channel 6 at 2437 MHz)
- It's also a cane
- We are able-bodied and don't need a cane at the moment, but we're hardly letting that stop us
- It uses a TP-Link TL-WN722N V1 wifi transceiver, a Raspberry Pi Zero W, and a USB battery bank as its onboard electronics
- The transceiver is capable of 20 dBm TX and around -90 dBm RX
- Maximum range is measured in kilometers

Show thread

- Typical operating mode: Cane keeps the Pi Zero's onboard transceiver broadcasting a very low-power hotspot, which we use to connect over SSH and control the main transceiver in monitor mode
- Can also act as a wifi repeater, either to gain connectivity from distant hotspots or launch a nearby hotspot to a distant device
- Due to attenuation through building materials, it can rarely reach more than a few tens of meters in dense urban areas
- Battery lasts for 12 hours of constant use

Show thread

- We could probably use it to try to break into poorly-secured hotspots, but as far as we are concerned, actual cracking is a boring use of aircrack-ng, and we prefer to use it for information gathering and exploration instead, or for remotely accessing our other RPi-based creations.
- Being a decent direction finder, it's also useful as a bug sweeper for motels and B&Bs.
- It comes in just under the wire for FCC EIRP limits, and is not illegal.

Show thread

- this particular cane has no ability to interact with the 5GHz wifi band, which we do consider to be a significant issue. we are working on making a miniature version (it will end up being a bit less than half the length, same proportions) as well, but we have some fiddly bits to work out on that plan.

the miniature version will either a) be its own thing (a concealable dagger-like instrument) or b) attach to the back of the cane handle of this one, in-line with the existing boom.

Show thread

we may end up making both of these options, just so we can have both a large versatile instrument and a more specialized, easily concealed smaller one that can't do 2.4 GHz but can be brought into more places.

Show thread

we suspect that 5GHz wifi will soon be the most common, if it isn't already, since its characteristics are really quite a lot more favorable in dense urban environments and its speeds are faster, so pragmatically speaking, handling 5GHz only is probably better than 2.4GHz only.

Show thread

making the 5GHz antenna detachable from the cane like the Rakuyo in Bloodborne would be badass as fuck but we aren't really sure how to make it work

Show thread

@diodelass bun only understood half of these things but is very impress and wants to touch the shiny now

@diodelass Do you have to point it at/orthagonally to your target, or how does it work?

@petra it's an endfire antenna, so you aim it right at the target like a rifle. it's not perfect or anything, so you hear and are heard by lots of stuff that's far off-axis or even behind it, but the direction of maximum intensity is straight off the end of the boom.

@diodelass we’ll need to meet each other after the apocalypse. Stuff like that will be needed to rebuild networks and I know nothing about wireless networks (but a lot about wired l2 and l3/4)

@wxcafe hopefully, we'll have time to build our planned 900MHz LoRa cane, 5GHz 11ac dagger, and helical EMP rifle before the apocalypse arrives and cuts off our supply lines.

Sign in to participate in the conversation

Cybrespace is an instance of Mastodon, a social network based on open web protocols and free, open-source software. It is decentralized like e-mail.