Neversink Telephony

As Ellie wrote in the last blog post, we gave an in-progress tour of the sculpture site on Sunday. It was a great success! We’ve made amazing progress in the last two weeks, between the sculpture and community interviews, but the technology side of things is still a work-in-progress. Our residency here in Claryville is coming to a close, but work will continue on a couple key aspects of the technology leading up to our exhibition in October.

What I’ve been able to get working so far is pretty close to what we’d originally proposed; a local wireless network that provides access to the archive and a short-range radio broadcast of our audio material (more on that soon!).

The element that’s still missing, but important to the project, is a telephone interface for collecting new material and listening to what we have so far. While the web interface is definitely the best way to hear the interviews with accompanying photos, access to fast enough internet connections here in the Catskills is far from common. But telephones, of the land line variety, are ubiquitous here. Offering the opportunity to call in to the project over a local land line would allow much wider participation, and would allow us to continue growing our archive while Ellie and I are back in New York City.

The basis for this system is a popular Open Source program called Asterisk. It’s the Swiss army knife of phone systems, it can do almost anything related to voice telephony. In recent years its most popular mode of operation is Voice Over IP (VoIP). VoIP is kind of like Skype, it’s inexpensive for long distance calls but requires fast internet access.

Asterisk also allows you to plug into an analog phone jack using a special expansion card for a PC. The advantage of this analog approach is that people nearby can call into your local number for free. Back in the mid-90s, before VoIP and widespread broadband adoption, this was the best option available for a small business wanting to run a customer support line. Unfortunately as internet-based telephony has exploded in popularity, its analog counterpart has received less attention. As a result, building the phone system was a bit more challenging than I’d expected.

Analog telephone jack installed in the server.

I did manage to get the expansion card working on the Linux server I’d brought up, but frustratingly it would stop working unexpectedly. After looking through the troubleshooting documentation, I’ve diagnosed the problem as being related to IRQ interrupts, an archaic low-level component of computer hardware. Specifically, the card needs a dedicated IRQ number, and it was sharing one with the Ethernet networking card. One solution for this type of IRQ conflict is to simply move the card to a different slot on the motherboard. And, alas, my server only has a single slot.

So I’m going to try again with a different computer once I get back to Brooklyn. I’m still hopeful that with a little more tinkering I’ll be able to sort out the technology needed for the community phone line. I’ll update the blog with my progress!

The Asterisk expansion card.

A new possibility for the server for the telephony portion of the project. It's an older machine with several slots, enough to provide for a dedicated IRQ number.

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One Response to Neversink Telephony

  1. Pingback: is growing | The Wildcat Fellowship Program

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