NuTone Appliance Maintenance

My house was built at a time when things were made to last. However, some things are hard to maintain. Hidden appliances, like the kitchen fan, is an appliance that nobody thinks about until it starts making sounds or, in my case, little pieces of dirt rained down when it was turned on. I’m pretty sure it hasn’t been cleaned since it was installed 65 years ago. The entire motor housing and duct was covered with a thick layer of grease and dirt. It was time for some appliance maintenance.

The fan manufacturer, NuTone - best known for making doorbells - made fans primarily for residential homes. My grandmother had one above her kitchen sink that vented out the wall.  There was a pull chain to turn it on.  I remember her climbing up a stool and straddling the sink to clean the fan. My mom stood behind her the whole time waiting to catch her if she fell. These fans were stout, quiet and worth a bit of money if maintained.

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Eclipse 2017 Balloon pictures

This blog post contains images from the balloon taken by two of the three Raspberry Pi Zero cameras on-board.  Unfortunately the third suffered catastrophic data loss (probably upon landing) and everything on its SD-card was lost.  One of the Pi cameras faced outward from the side of the payload and the other at about a 30° angle off of straight down.

About 5 minutes after launch.


Looking at Shoshoni, WY soon after launch.


Totality approaching.  Balloon altitude is about 28,000 feet (8500 m).


Shadow approaching on the ground.


Start of totality in the clouds.




Shadow receding on the ground.


And in the clouds…

At about 45,000 feet (13,700 m).  Temperature outside is about -58 F (-50 C).


About 80,000 feet (25,000 m). -12 F outside (-24 C).


The ground from near the highest point the balloon reached (94,000 feet/28,600 m). It took about 3 1/2 hours to reach this.


Just as the parachute burst. Decent was 27 minutes.


Just about to land. Balloon all tangled up.


A SSDV photo received by the launch team shortly after launch. Some packets lost.


Short youtube video showing eclipse

Stephen in the news

Member Stephen Chavez has been making waves again — following his presentation with an SSD member at Defcon 24, he travelled to China and won an award at the GeekPwn 2016 hacking contest.  And now, just after his graduation from Metro State University in Denver, he has been featured on Denver’s 9News.

Stephen and friends have been hacking his electric wheelchair with the goal to make it semi-autonomous.  Unable to talk, he uses a computer keyboard to communicate; a task that cannot be done while controlling the chair’s joystick. As a result, he cannot “talk” and “walk” at the same time.  With a semi-autonomous chair, he can set it to follow a friend or drive on a path while avoiding obstacles — freeing his hands to type and communicate.

Stephen’s wheel chair is a product of PGDT.  The chair utilizes a proprietary protocol that runs over the same CAN interface found in all late model cars and trucks.  PGDT calls the protocol R-net.  R-net is deployed on the wheelchair to allow the various devices and interfaces on the vehicle to communicate with each other.  There are no public documents about the R-net protocol.  Stephen worked with a team of hackers to reverse-engineer this protocol and take control of the wheelchair’s internal network.  “We’ve learned that power wheelchair hacking is also closely related to car hacking”

Stephen Chavez. Photo by Sara Hertwig

Stephen Chavez.
Photo by Sara Hertwig