The Treehouse Blog

Several years ago, the PA state government began deploying a proprietary trunked communications system… and encouraged County governments to use it. Since it’s proprietary, the governments are locked into the price structure of a single vendor (brilliant! bravo!) and radio enthusiasts like me won’t be able to use our scanners to listen in (at least, not anytime soon). I’m a big fan of government transparency and openness… and this is moving in totally the wrong direction. All isn’t immediately lost however. Even if fire and ambulance dispatch is handled with OpenSky staring on June 1st, 2006 as this article says, it sounds as if paging will still be simulcast on traditional FM frequencies so that voice pagers, sirens, and scanners can function without an upgrade. It seems that radio geeks aren’t the only ones concerned… just listen to those fighting fires.

And while I’m ranting… Since this system is IP based, how long will it take before a laptop in a state cop’s car contracts a virus because he installed an unauthorized Wifi card, and cripples communications state-wide? Consultants won’t go hungry cleaning it up, that’s for sure.

No structure here… just some random goings-on:

For the last several kernel updates for FC4, my DVD sharing using GNBD hasn’t worked. I guess those special ioctl()s aren’t getting translated over or something. And NFS or SMB sharing an encrypted DVD just doesn’t do anything good at all (ignoring the fact that NFS seems really sucky with the latest FC4 updates). So, after months of not being able to watch DVDs, I gave up, and bought a USB drive cage to attach a DVD drive to Oak. Works perfectly. Despite performance issues and cabling evilness, I still can’t completely rule out a stack of USB drives RAIDed as a bulk storage solution, especially with all of the device mapper coolness in Linux. Too early to be thinking of that, though, as the computer storage fund hasn’t matured yet, despite the fact that Oak is at 99% capacity.

As Doug has mentioned, Asterisk and VoIP is still pretty neat. I’ve setup a teliax account, since they have pricing like nufone with a whole lot of rate centers worth of DIDs (they’re essentially a Level3 reseller). So, we just need to get some VPN’ing set up. I’m in desperate need of some UT, and I think VPN might be a useful substitute for a LAN party this winter.

My grandfather (on my Dad’s side) has been in the hospital on and off for more than a month now. Currently he has pneumonia, is very weak, and not entirely coherent. Your prayers would be appreciated for what could be a difficult Christmas season for the family.

Things at Ship are going fairly well. I did shoot myself in the foot with the “ip arp inspection” feature of the Sup720 this week though. Does 15 pps of ARP traffic seem like a good default threshold for shutting down trunk ports to you? Me neither. Of course, I asked that question after two ports had been err-disabled. Hopefully Tim and I will get to do a real test of some VMPS soon, too.

This week I have been playing with my new PRO-2052 scanner. I bought this model because it has an RS-232 interface that can be used to control it. There is a free piece of software, sctl, that allows you to use it in Linux. I have had to tweak the code a bit for my purposes. I needed line buffering enabled to interface sctl with a PHP script, and also had to change the interfacing to make the ‘sreport’ function work with my model. I’ll probably post a patch at some point. So far, I’ve written a few cheesy scripts to log radio transmissions into a database and play them back. It’s not quite perfect, but it is doing what I want. It would be nice if this guy would release his source. I’d love to have the two-tone pager decoder that he has.

I’ve also been poking around various scanning sites. It looks like there still isn’t any progress decoding the OpenSky system used by the state of PA. Apparently it’s VoIP based. I also found a site with audio samples of various digital transmission modes. Many of the sounds are familiar from old movies and such. I think the PSK-31 sound is sortof like the bridge ambient sound from Star Trek TOS. Also found a great PDF with lots of communications tone tables, for Motorola Quick Call and others.

One of the things I wanted to take care of this summer was some type of outdoor lighting to be used when coming home at night. There just isn’t enough ambient light to figure out how to insert the key into the lock. I was considering LED lighting built into the deck, outdoor lights around the deck, and automating the existing outdoor lighting. Seeing this as an opportunity to finally begin playing with X10, I dove in.

The first phase was to control the deck and garage outside lights with a wireless remote. I purchased some X10 light dimmer switches to replace the light switches, a wireless transceiver, and a remote control. Everything worked well except the remote range seems a bit short. Latency wasn’t bad… probably a little less than a second.

Phase two involves the hall light, and a computer interface. I bought a PowerLinc USB and downloaded the WISH / x10dev software. The only “gotcha” for the software was that it assumes your hiddev0 is in /dev/usb whereas mine was in /dev. The error messages were not at all helpful in figuring that out, unfortunately. At this point the interface worked, but I had some phase issues: my two lights were on one phase, and the computer interface was on the other. Instead of building or buying a phase coupler, I went with Doug‘s suggestion of moving breakers around instead. They’re really about the easiest plug-and-play devices in existance, but it was something that I had never done before, so I certainly turned off the mains. My current unresolved issue is that the latency between issuing a command on the computer, and the device receiving the command, is aboud three seconds… way too long, especially if you want to do about six commands for a single event. Still haven’t figured out if this is as fast as the interface goes, or if there is a software bottleneck.

So, there’s my X10 project summary. I’m pretty happy with the results so far. It’s not incredibly cheap (I’ve spent about $100 to control three lights… albeit with a wireless remote and computer interface), but it has achieved the goal, and now I know a bit about X10 🙂

The weather this week has been just great. And I’ve even had the opportunity to take advantage of it. Sunday, I had a family picnic which I used as an excuse for a rather long hike up and down a mountain.

On Tuesday evening, Chris and I walked a 2.5 mile stretch of the Tuscarora Trail that runs along the top of a mountain. Of course, it got dark, the flashlight wasn’t where it was supposed to be, and the return trip was rather interesting. No broken limbs, but lots of scratches and such. This wasn’t your nice dirt road kind of trail either – just rocks and the occasional blaze for much of the trail. The cell phone provided a good deal of light towards the end, despite accidentally calling Tim.

On Wednesday, Ian and I hiked (on a trail that was like a dirt road) almost 9 miles. It was pretty dark at the end, but a lot nicer than stumbling over rocks. It was one of the few times I was with Ian this summer, so we had the chance to catch up on all of the happenings since the Spring semester.

Now, Doug‘s turn should probably be next… but I haven’t decided on the appropriate successor to last summer’s infamous pipeline hike 😉