Electromagnetic Field 2024

Well, another Electromagnetic Field has been and gone and it seems analogue telephony is more popular than ever (Take note BT). For those of you that haven’t been, Electromagnetic Field describes itself as “a non-profit camping festival for those with an inquisitive mind or an interest in making things: hackers, artists, geeks, crafters, scientists, and engineers”. It takes place every 2 years, and this is the second time we’ve ran a site-wide “copper” telephone network with support for faxing, dial up internet, bulletin boards and more.

Things started off optimistically. We’d done lots of interoperability testing with the Phone Team to ensure calls between DECT / POTs worked and subscribers could claim memorable numbers. These had both proven troublesome in 2022 so it was a relief to know everything worked before we arrived on site. We were also arriving a day earlier than in 2022, with a plan to pootle around the site in the van chucking the Voice Gateways into the DKs on the Monday (Day -2), giving us two whole days of tweaking before the event officially started. No stress! Then reports of vehicles getting stuck in the mud started coming through. It can’t be that bad can it? Well, things were so bad a tractor got stuck, so a transit van fully laden with e-waste had no hope.

We arrived on site and whilst things weren’t quite as biblical as we had envisaged, vehicles weren’t permitted to drive on the grass due to the risk of getting stuck. Fortunately we managed to locate a bit of sought after hard standing to ditch the van, pitch a tent, and pray for the forecasted dryer weather. Alas, we woke up on Tuesday (Day -1) morning to the sound of heavy rain which postponed the deployment again, but we did manage to borrow one of the 4WD Utility Vehicles and start putting up phones around the site - so things had at least started moving in the right direction.

On Wednesday (Day 0) we managed to finally start getting Voice Gateways into DKs thanks to the NOC team and some fine chaps from the ECHQ Village. At this stage we were massively behind schedule, and when the site opened to the public on Thursday (Day 1) at 10am we only had 5 out of 25 Voice Gateways online, with many of the others unprovisioned or not appearing on the network at all.

A brief epiphany later and we recalled that many of the gateways were running config from the previous EMF, and a Network ACL was blocking the response from the DHCP server due to a subnet change. With some quick twiddling of IPs we managed to connect to them, remove the ACL, and then re-provision them to bring them online. By the end of the day we had 22 out of 25 gateways up, so by the time most attendees had put up their tents, wandered around the site, found their fax machine and plugged it in they would have had service, so all was not lost.

On Friday morning we wandered around the site with a laptop and console cable to bring the remaining gateways online:

• One was failing to boot with an error about bad RAM so it was swapped out with a spare pending further investigation.
• One escaped the ACL removal so it was manually wiped, and re-provisioned.
• One was found to have no subscribers nearby and was rather close to a massive Tesla Coil (The two might be related) so it was disconnected without setting it up.

With everything up and running we could finally relax a bit.

It’s fair to say engagement with the phones was absolutely phenomenal this year. There were several phone based games running, including Capture the Phone created by @2E1PKY@mastodon.radio which had 63 players and 808 captures across the event, and the Bodgeham Badger Info Line that had 98 people register to report badger sightings. Other telephone services included the Rats Facts Hotline which received 269 calls, the Racoon Hotline with 147 calls, “I am Tom Scott” with 72 calls, and the Cat Fax service with 25 faxed cat facts, as well as many others.

@lpbkdotnet@mstdn.social bought a real, 70 year old Strowger Telephone Exchange that was clattering away in Null Sector - it was great to see EMF’s rich history of communications get a bit more historical!

@baljemmett@mastodon.online created the incredible Electromagnetic Field 2024 - Live Viewdata service, a hark to the 1980s Prestel service. It provided the real time schedule, bar prices, and a phone book, and attracted a hoard of people during the demo sessions held at the ECHQ village. It’s currently still online if you want to check it out.

@lexbailey@tech.lgbt also built a (probably) world first, a ZX Spectrum Laptop complete with modem, tape recorder and telephone - and even went as far as putting a battery and DECT adapter inside to make it truly portable. You can view a video on how it was constructed on Youtube

We’d like to take this opportunity to extend a massive thank you to everyone who helped make EMF what it is – the organisers and volunteers, the speakers, the makers of weird and wonderful gadgets and installations, and the amazing attendees.

We’d also like to give a special thank you to the NOC team that facilitated weird requests like “Can I put 120 modems in your fridge data centre as it turns out they’re quite loud”, and assisted with the more mundane side of deploying equipment, the Phones Team for building and operating the core platform, the numerous people that helped mount phones, run cables, stick equipment into DKs, created a fun game/app to dial into, and anything else that helped make the POTS network what it was.

We intend to be back at the next Electromagnetic Field event, and we hope to see even more phones, modems, fax machines, and fun things to interact with. If you have an idea you’d like to run by us, or you know of an event that’s desperate for some analogue telephony please get in touch,

Finally, the stats!

• 106 Activated Lines - Over double that of 2022
• 4879 POTs calls made over the event
• 3491 Calls made to / from the Public Phones around the site
• 4 Viewdata users!
• 2 people actually used Dial Up Internet?
• 70+ faxes to the Fediverse / Twitter / Bluesky
• 15 NyanFaxes
• 3+ Rick Rolls by Fax

See you next time!