NanoVNA is a small handheld Vector Network Analyzer (VNA). It is equippedwith lcd display, portable device with battery(battery not included). This project aim to provide an RF gadget but useful instrument for enthusiast. The device hardware offers 50k-300MHz frequency range that can be expended up to 900 MHz (with somewhat less dynamics on higher frequencies). →
In search for some cheap and useful RF test hardware, I came by Geekcreit® Spectrum Analyzer USB LTDZ_35-4400M_Spectrum Signal Source with Tracking Source Module RF Frequency Domain Analysis Tool at sale price of aroundy $30/EURO30. It looked to have quite promising specifications: Attribute: RF frequency domain analysis tool Interface: usb Power supply: usb Standby current: →
https://www.smbc-comics.com/comic/a-guide-to-science-writing →
Here is some telephone history from Tekniikan museo museum located at Helsinki Finland. Here is once possibly the most common phone model used in Finland (Ericsson Dialog from 1964). Ans one very old telephone Here is the first automatic telephone center in Finland from 1922. Those pictures were taken few months →
I had some problem with breakers tripping. Then the source of the problem turned to be this extension cord made by Bachmann. Sparking and blackening outside and also inside It seems that child protection mechanism failed and part of it was stuck between contact bars. This then caused sparking on contacts, which caused blackening. End →
This posting is here to collect cyber security news in August 2019. I post links to security vulnerability news to comments of this article. If you are interested in cyber security trends, read my Cyber security trends 2019 posting. You are also free to post related links. →
https://blog.hackster.io/how-to-spot-pseudoscience-on-the-internet-e7d1f53796a2 There are many companies that make up some bogus pseudo scientific claims to sell products. This article gives an example about a company selling expensive stickers as solution for people afraid of the irrational “dangers of electromagnetic radiation”. The article lists the hallmarks of pseudo-scientific products for you to become a more savvy consumer. →
https://www.electricaltechnology.org/2018/08/electrical-shock-hazards-its-effects-on-human-body.html When working with or nearby electrical installations an electrical shock, arc flash or arc blast can occur and a current can go through the body, due to the following situations: Direct contact with live parts of the installation (exposure to live parts) Contact with parts that normally are not live, but as a consequence →
In Greece the standard mains power voltage is 230 V and frequency is 50 Hz. The power plugs and sockets are of type C and F. This is same that are used in Finland, so I did not need any traver adapters (that often have questionable safety). This is interesting wiring at hotel – proper →
https://www.cbc.ca/news/canada/newfoundland-labrador/hearts-content-transatlantic-subsea-cable-150-anniversary-1.3695418 150 years ago a single cable forever changed the way the world communicated, as the first successful transatlantic subsea cable, able to send and receive telegraphed information, solidified a link between the old world and the new for the first time. →