Archive for May, 2010
Tales of X10
by balleman on May.28, 2010, under Happenings, Technology
A few years ago, I decided to improve the light switch situation in my garage. The garage had lights at either end controlled by pull strings. It was a frequent hassle to walk from one end to the other, often tripping over a variety of obstacles, to get both of them on or off. Having already deployed X10 to control a few things around the house, it seemed like a reasonable and economical idea to use X10 here as well. I used two LM15As for load switching, two SS13As for control near both doors in the garage, and an RR501 to tie everything together. Initially, the project seemed to be a great success.
Then it becomes apparent that the SS13As are not that great. The adhesive backing would refuse to stick to the garage wall for extended periods of time, necessitating the addition of some screws to provide a slight ledge for them to sit upon. They are also battery powered, and the stock batteries were nearly useless in cold weather. Naturally, the colder times of year require the use of lights in the garage more often, and it became incredibly annoying to have to warm the switch with your hand and make multiple attempts to turn on the light… when the pullstring that otherwise would work is in reach. My suggestion is to never use SS13As in anything but warm environments, and probably just avoid them altogether. The one I had used inside would “forget” its code assignments and the coldness of the window sill was enough to keep it from working well.
To fix these issues, I revisited the idea of wiring regular three-way switches in the garage. With the layout of the existing wiring, even the most creative ideas would require two new wires run the length of the garage, with one of them likely needing to be a 3-conductor that I don’t happen to have laying around. And copper isn’t really cheap right now. So, X10 was again looked at for a solution.
I decided to go with hard-wired X10 controllers, specifically the XPT4-W. I installed these near existing wire locations with a minimal of effort – maybe 3 hours total. So, now I have fully functional control of my garage lights (probably even in cold weather), and didn’t need to run crazy amounts of cable for three-way switches.
Isn’t AMPS dead yet?
by balleman on May.10, 2010, under Radio
It was with some great fanfare that AMPS met its death on February 18th, 2008. But did it really die? As far as I can tell, all that happened on that date was that the FCC no longer required cellular providers to make AMPS available, and many did eagerly turn it off. But, unlike the conversion to digital television, there appears to be no requirement at this point for providers to abandon AMPS if it is still making them money. That being the case, are there any AMPS providers still out there? Public filings (available here) concerning AMPS status were made prior to the sunset date and reveal that some companies had a lot of AMPS customers still and had no plans to turn the service off.
Why do I care? Because I loathe 47 CFR 15.121 and would like to see it abolished. This is the section of FCC regulations that forbids the manufacture of devices that can receive, or be easily modified to receive, cellular frequencies. This requirement only covers the Part 22 Cellular Service (824-849, 869-894 MHz) and not the all-digital PCS and AWS bands that cell service has expanded into. With AMPS, conversations were transmitted using FM, and so could be easily decoded by any FM receiver that could tune to the appropriate frequencies. With the digital services, more sophisticated handling of the signal (and even decryption) would be required, which apparently made it unnecessary to have the same kind of regulation. As far as I know, this is the only restriction placed on what frequencies can be tuned by a receiver. On freedom grounds alone, I have a big problem with that. If AMPS does finally die – and I hope it does – I hope that 47 CFR 15.121 can die with it.