Monday, October 30, 2017

My Experimental Blog Site

I have set up a new marilynwolf.us for my books.  I can also use it to host this blog but the formatting system doesn't make it easy to feature both the books and the blog on the homepage. I have an experimental setup on marilynwolf.us.  Please go there, check it out, and let me know which you prefer. You can email me at wolf@ece.gatech.edu.  Thanks!

Sunday, October 29, 2017

Heathkit SB-303


This column has nothing to do with computing so far, but it might in the future. This is a Heathkit SB-303 amateur band receiver.  Great looking, isn't it?  And it is one of a line of several Heathkit ham radios. You can find here a very interesting article on the Heathkit SB line which started in the early 1960s and ran into the early 1980s.



Here is the guts of the radio. This is an all-transistor design; most of the SB radios used tubes. These were kits---this radio was built by someone who did a pretty good job.  It has also been restored by the previous owner. The large, electrolytic capacitors in the power supply tend to degrade over time and these have been replaced. The previous owner also repainted the case.

I am thinking about using one of these radios as the starting point for a hybrid digital/analog radio.  By tapping signals the signals in the radio and connecting them to analog/digital converters, I can ship them to a computer or FPGA for digital processing. Many software-defined radio rigs run at relatively low sample rates and so do most of their digital processing in the baseband.  A fancy data acquisition card could let me move the interface earlier in the radio, perhaps all the way to the first stage of amplification after the antenna. This sort of project would be a good way for me to get my hands dirty with software-defined radio; it would also be fun to compare the signal characteristics of the analog and digital versions.  All of these plans, of course, depend on time permitting from other projects and duties.  We shall see how things play out.

Monday, October 23, 2017

FAA Proposes Ban on Lithium-Ion Batteries in Checked-In Luggage

Gizmodo reports here on a proposal by the FAA to ban devices with lithium-ion batteries in checked-in luggage. They would like to see such a ban to be worldwide.  Their concern is based upon a test in which a lithium-ion battery caught fire next to a bottle of dry shampoo; the resulting fire was too fierce to be contained by aircraft fire suppression systems.

Monday, October 16, 2017

@Apollo50Wolf the Apollo Program 50th Anniversary Commemoration

I have set up a Twitter account, @Apollo50Wolf, for the commemoration of the 50th anniversaries of the events of the Apollo program.  Watch this feed for tweets on the anniversaries of Apollo events.  The feed will start with Apollo 4, an unmanned test launch, on November 9.

WiFi encryption vulnerability

Anandtech reports here on vulnerabilities in the WiFi encryption protocol. These flaws are in the WPA2 standard itself, not merely in some implementation of that standard.  The proof-of-concept attack, developed at KU Leuven, is known as KRACK.

Friday, October 13, 2017

Thursday, October 12, 2017

Autonomous Vehicle Test Track

NBC reports here on the Mcity autonomous vehicle test track at the University of Michigan.

Friday, October 6, 2017

Security Problems in Internet Cameras

Extremetech reports here on a report of a woman whose Internet camera was compromised, resulting in someone watching and talking to her.

AMD Embedded Radeon GPU

Anandtech reports here on the new Polaris-based embedded Radeon processor from AMD.

Thursday, October 5, 2017

New SD Cards for Industrial and Automotive

Anandtech reports here on a new line of SD cards from SanDisk targeted to the harsh conditions of automotive and industrial applications.