Hacker News Reader

rupellohnon Real-time map of Great Britain's rail network

It's fun to watch it side-by-side with https://www.youtube.com/@RailcamUKLive

rupellohnon A Cozy Mk IV light aircraft crashed after 3D-printed part was weakened by heat

Full report here: https://assets.publishing.service.gov.uk/media/69297a4e345e3...

The aircraft owner who installed the modified fuel system stated that the 3D-printed induction elbow was purchased in the USA at an airshow, and he understood from the vendor that it was printed from CF-ABS (carbon fibre – acrylonitrile butadiene styrene) filament material, with a glass transition temperature3 of 105°C.

An alternative construction method for the air induction elbow, shown in the Cozy Mk IV plans, is a lamination of four layers of bi-directional glassfibre cloth with epoxy resin. The epoxy resin specified for the laminate has a glass transition temperature of 84°C, after the finished part has been post-cured. The aircraft owner stated that as the glass transition temperature listed for the CF-ABS material was higher than the epoxy resin, he was satisfied the component was fit for use in this application when it was installed.

A review of the design of the laminated induction elbow in the Cozy Mk IV plans showed that it featured a section of thin-walled aluminium tube at the inlet end of the elbow, where the air filter is attached. The aluminium tube provides a degree of temperature-insensitive structural support for the inlet end of the elbow. The 3D-printed induction elbow on G-BYLZ did not include a similar section of aluminium tube at the inlet end.

rupellohnon What Americans die from vs. what the news reports on

https://en.wikipedia.org/wiki/Man_bites_dog

rupellohnon I stopped using AI (as a Senior Software Engineer) [video]

spoiler - he hasn't stopped using AI: https://youtu.be/w3EZpcTZ4ZA?t=856

rupellohnon What is VRAN: Virtualize Your Radio Access Network

I've been out of the industry for a few years, but can anyone explain how L1 RAN processing can be done 'in the cloud' without back-hauling huge amounts of raw RF data to a data-center?

rupellohnon Null Island is one of the most visited places on Earth, and it doesn’t exist

Strava shows some interesting artifacts there:

https://www.strava.com/heatmap#13.00/0.00000/0.00000/hot/all

rupellohnon Ask HN: Advice about aging parents

I recommend reading 'Being Mortal' by Atul Gawande for some good insights into dealing with end-of-life issues. My wife & I found this very helpful in making decisions around the care of her aging father.

https://www.economist.com/books-and-arts/2014/10/04/helping-...

rupellohnon More and More Americans Are Smoking Pot. What Does That Mean for Their Health?

Interesting comparison of use (& abuse) of THC & Gabapentin

https://www.youtube.com/watch?v=K-ZCzmZLSrc

rupellohnon USN AN-1 Submarine Aircraft Carrier (2018)

> ... landing a much less stable VTOL on a tiny submarine without any sizeable flight deck in the 60s was completely out of the question

Reminded me of this incident where a Royal Navy Harrier landed on a container ship. https://www.airspacemag.com/military-aviation/oldies-amp-odd...

rupellohnon Ask HN: Who is hiring? (May 2020)

HawkEye360 in Herndon, Viriginia operates a first of its kind commercial satellite constellation to identify and geo-locate a broad set of RF signals.

About our technology: https://www.he360.com/technology/

Openings: https://hawkeye360.applicantstack.com/x/openings

- Project Engineer - Satellite Engineer, Flight Dynamics - Senior Data Scientist - Senior UI Developer - Software Engineer - Space Team - Sr. FPGA Software Defined Radio Engineer

Feel free to contact me directly, rupert at he360 dot com

rupellohnon Ask HN: Who is hiring? (November 2019)

HawkEye360 in Herndon, VA operates a first of its kind commercial satellite constellation to identify and geolocate a broad set of RF signals.

We have openings for Software, DevOps and FPGA Engineers.

About our technology: https://www.he360.com/technology/

Openings: https://hawkeye360.applicantstack.com/x/openings

Feel free to contact me directly, rupert at he360 dot com

rupellohnon Ask HN: Who is hiring? (September 2019)

HawkEye360 in Herndon VA operates a first of its kind commercial satellite constellation to identify and geolocate a broad set of RF signals.

We have openings for Software, DevOps and System Engineers.

About our technology: https://www.he360.com/technology/

Openings: https://www.he360.com/careers/

rupellohnon Reverse Engineering a 433MHz Motorised Blind RF Protocol

Nice write-up! - I strongly recommend looking at dspectrum for those interested in reversing these kind of devices:

https://github.com/tresacton/dspectrumgui

"The goal of this app is to make it trivial to demodulate common RF signals, and provide a digital worksheet for your reverse engineering efforts."

rupellohnon Identifying HTTPS-Protected Netflix Videos in Real Time [pdf]

The fingerprint is derived from the aggregate size of all packets that comprise a segment of video (what the researchers call an ADU),

Some possible counter-measures are discussed in the conclusion:

"To that end, we believe that Netflix could defend against passive traffic analysis by ensuring that the byte-range portion of the HTTP GETs sent by the browser do not perfectly align with individual video segment boundaries. For instance, the browser could average the size of several consecutive segments and send HTTP GETs for this average size. As an alternative approach, the browser could randomly combine consecutive segments and send HTTP GETs for the combined video data. Designing obfuscation techniques for VBR DASH streams that do not degrade video quality remains a potential area for future research."

rupellohnon Why is my NTP server costing $500 per year? Part 1 (2014)

Could this have been the result of an NTP amplification attack? https://www.us-cert.gov/ncas/alerts/TA13-088A

rupellohnon Stealth Cell Tower Disguised as Printer

For 3G/4G networks there is strong mutual authentication between the device and the network, for 2G(GSM) networks only the device is authenticated so these interception devices work by jamming the 3G/4G bands forcing the device onto the (fake) 2G network.

rupellohnon The many lives of John le Carré, in his own words

My favorite le Carré book, 'A Perfect Spy', is largely based on his unconventional early life. I'm looking forward to reading his memoir.

rupellohnon What I learned as a hired consultant to autodidact physicists

I recommend 'Physics on the Fringe' for anyone interested in this topic

http://physicsonthefringe.com/page/about-book

rupellohnon Exploiting WPA2 in a City Wide Wi-Fi

Here is a nice write-up on how 802.11x security was provided to attendees at 32C3 (they used TTLS with no client certs and users could choose their own user/passwords anonymously)

http://mobilesociety.typepad.com/mobile_life/2016/01/wifi-ce...

rupellohnon MicroPython, a few years on

For regular Android apps using Python you might want to look into Kivy: https://kivy.org/docs/guide/android.html

rupellohnon Why didn't France adopt the longbow like England did?

Thanks for posting this!

my favorite bit:

"He startled train conductors and passengers by throwing his briefcase out of the train window each day on the ride home. He later explained that he was tossing his case into his own back garden so he would not have to carry it from the station"

rupellohnon Google, Microsoft, Comcast Say Verizon’s New Cellular Tech Could Wreck Wi-Fi

Here is the actual study - it is an interesting read: http://apps.fcc.gov/ecfs/document/view?id=60001078145

In a nutshell; the LTE transmission cycles on and off on a regular cadence without sensing if the channel is clear. This tramples over the 802.11 frames and results in higher utilization of the medium than that which is claimed by Qualcomm