Wednesday, October 29, 2008

Wetness Sensors

I jumped in and picked up a bunch of wetness sensors mentioned here. I'll be using them under sinks, behind toilets, under the water heater and the AC drip pan. These will work great with the eternal DS10A deal.

Haven't had much time for automation the last few weeks. I am experiencing major X10 noise problems for the first time. Three different light switches upstairs are intermittently controllable and one turns on by itself. I spent an hour unplugging just about everything in the house, but no luck. I tried changing house and unit codes too. It's very odd as everything was working great 3 weeks ago but I haven't plugged in anything new. Sometimes, device power supplies will all of a sudden start spewing noise onto the powerline, but those have been easy to track down & put on a filter. I'm a little stumped right now and considered replacing them the light switches with UPB ones, but they are so expensive.

Saturday, October 11, 2008

Current Sensing the Dryer

I got a few of the current sensors mentioned in this thread to monitor if certain devices are powered on. The first one I used on the dryer. I opened up the small access panel where the plug is terminated (as mentioned here), disconnected a leg, peeled it apart from the rest of the power cable and inserted it through the current sensor. I turned on the dryer to test it out (it was on the 'air dry' setting), but the sensor didn't activate because the heater wasn't on. If I switched it to a heated cycle, the sensor triggered. So I had to move the current sensor to the other leg, which is active whenever the dryer is on. After putting everything back together, I attached the sensor output to a DS10A so that it can send the dryer's power status wirelessly. Now, whenever the dryer turns on, the laundry room exhaust fan turns on and when the dryer is done, the laundry fan turns off 2 minutes later.

Thursday, October 9, 2008

Camera Server Efficiencies

Our CCTV system has been hacked and pieced together over the last 10 years and became more convoluted than necessary. Now that the Avermedia setup is running, I've been able to simplify things quite a bit. Our system previously used an IR controllable 4-1 composite video switcher to select an active camera based on user input or motion sensors. The automation server would use this feed to take snapshots of the activity. Each camera was also modulated so we could view them on our TVs or Slingbox. Now, the Avermedia records all 4 cameras based on its software motion detection. Also, the software is running full screen as a quad viewer. Since the server is headless, I've connected a VGA to composite video converter and modulated that output. This allows me to remove 3 modulators and the video switcher while still allowing the automation server access to all 4 cameras (albeit smaller views). Finally, an old series 1 TiVo was recording the camera feed continuously and that too got turned off along with its modulator.

Tuesday, October 7, 2008

Mediasonic HD9-U2LA NAS

I bought a few things off of eBay of late, taking advantage of the 30% cashback from One of those things is Mediasonic HD9-U2LA NAS. It's a very simple NAS device that takes an IDE drive up to 1TB and has both a 100 Mbps ethernet connection and USB 2.0. Performance is not great - it looks like it sinks about 15-20 Mbps, but that's OK for my needs. Another annoyance is it uses FAT32 so file sizes are limited to 4GB. On the plus side it's fanless and quiet, relying on its aluminum casing to dissipate heat. Unlike a lot of cheap NAS cases, this one features a configurable idle period before the hard drive is powered down. For me, this is a key as the NAS is just for weekly backups run in the middle of the night. I suppose I could put it on an appliance module and power it on and off when I need it. I'll measure its power consumption later today.

Update: It uses 4 watts with the drive powered down and 11 watts with it active.

Monday, October 6, 2008

Airave Update

We've had the Airave a few weeks now and it works nicely. We've now got a solid signal for our Sprint phones and the quality is very good. Dialing out takes about 1-2 seconds longer, but incoming calls are seamless as is the transition to regular cell towers when we leave home.