The more they change, the more they stay the same - almost

Third in a series on the streaming eagle nests. See the first and second.

I've put this article under the "Computers in use" topic as this is what it's all about; the use and abuse of computers today. I've been in and around computers since back in the days when a "small" computer took up most of a large room and needed special power and cooling. Maybe they weren't exactly steam powered, but they could sure produce steam if the cooling pumps quit.

Today we have multi-media computers - little boxes that combine digital controls and presentation with the older-style analog cable-vision systems. Tomorrow we'll have completely digital media - maybe even later today, things are progressing so quickly in that direction. The Windows Media encoder that Ed Clunn helped me put together straddles the line between analog and digital. It has both an audio and video section that take in traditional audio and TV (composite video) signals, and software that turns these into a stream it can send to a receiving system, which then can feed the tens of thousands of eagleholics that ended up wanting to watch Doug's little nest.

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The camera signal came into the house via a piece of "cablevision" cable - technically, RG-11 with a steel "messenger" which was designed to hold it up when strung between support poles. Bob Chappel has found a very nice little device (actually a mated pair) that multiplexes power, audio and video onto the single cable. It can run the signals up to a mile over the right cable (needs to be low enough resistance that the power doesn't drop off too much) and comes with its own variable power supply.

Bob made do with some old Ethernet (thin net) connectors and had to solder them to the cable as they didn't fit properly. Making the same mistake would cost me time on the Victoria nest install. From here, the video went to a Doug's VCR and his spare TV. Doug watched the nest continuously during the nesting season, and recorded interesting things via the VCR. He accumulated about 13 hours of VHS tapes this way during the 2005 season, and wanted to continue to be able to do this for 2006.

I had come prepared to convert a "true" cablevision signal into the types I'd need for the encoder, having purchased an inexpensive DVD recorder/player that included an TV tuner and cablevision input/output. Since I didn't know the details of the camera connection except that it was "cable" I'd made the assumption that there was a "modulator" at the camera end that turned the separate audio/video into a regular channel (usually channel 3 or 4) and that I'd have to pull it apart again. Finding the little VDS box that Bob had used actually made things easier since they were already separated when they left it.

I had come prepared with a bunch of Y connectors (RCA female to 2 RCA male), again, just in case. These came in handy as I had to split each of the video and audio into 3 streams for the 3 different destinations: Doug's original VCR, the encoder, and the video archive box. In addition, the mono audio had to be split to feed both sides of the stereo inputs on each. The mass of them looked ugly but worked fine. It sure was a good thing that I'd found a "dollar store" with these cables all at $1 each. If I'd had to pay normal retail the small bundle would have been worth something like $100 and the additional cables strung along the floor to the boxes would have added another $50 or so.

I also brought a couple of battery backup (APC 450 UPS) boxes. A friend (thanks Greg) had given me a number of these that had been taken out of service due to their batteries being old - and I had only needed to put fresh ones in. One went on the camera feed and video server, and the other on the main encoder and network gear. Hornby actually has fairly reliable power I'm told, but brown-outs happen sometimes and these units protect against surges too.

An old 10Mbps Ethernet hub split the incoming ADSL line so we could put the encoder directly onto the net and hide both Doug's computer and the video server behind a firewall/router. The Telus plan only allowed for 2 IP addresses but this was enough.

I was a bit concerned over the wiring leading to the modem. The DSL spec. allows for a 6' piece of un-twisted cable from the wall to the modem, but expects that the rest of the run is properly installed "twisted pair" telephone-grade copper cable. Instead, I saw the tail end of what looked like a telephone extension cord - not twisted - leading down through a hole in the floor. A little investigation showed that this was in fact just the end of a chain of such extensions running through a crawl-space, across the ceiling of the downstairs sitting room, and up into the bottom of Doug's desk to where the main phone was. DSL does not like this kind of cable as it allows interference and can sometimes cause complete failure of the link. I vowed to replace it as soon as I could, but had not brought the necessary cable or tools I'd need. It had to wait.

Ed and I had set the encoder up to watch its S-video input, so I installed the DVD recorder anyway, and used it's capabilities to both amplify the signal somewhat and convert the composite (RCA) video to the S-video. This saved me some of the Y connectors but complicated Doug's life one day when the power went out (I hadn't put the DVD player on the UPS) and he had trouble getting it set up again.

I got everything installed and after checking with Ed that the video was showing up at their receiver, had time to catch the last ferry off Hornby at 6PM that day.

Next - Captured video takes a LOT of space.