Tag Archives: Satellites

Radio Waves: Plant-powered Satellite Comms, BBC Pips, Filter Basics, and Replacing Shortwave

Radio Waves:  Stories Making Waves in the World of Radio

Because I keep my ear to the waves, as well as receive many tips from others who do the same, I find myself privy to radio-related stories that might interest SWLing Post readers.  To that end: Welcome to the SWLing Post’sRadio Waves, a collection of links to interesting stories making waves in the world of radio. Enjoy!

Many thanks to SWLing Post contributors Marty, Dennis Howard, Dennis Dura, Kris Partridge and Richard Langley and for the following tips:


Plant-powered sensor sends signal to space (Phys.org)

A device that uses electricity generated by plants as its power source has communicated via satellite—a world first.

[…]The device can inform farmers about the conditions of their crops to help increase yield, and enable retailers to gain detailed information about potential harvests.

It transmits data on air humidity, soil moisture and temperature, enabling field-by-field reporting from agricultural land, rice fields or other aquatic environments.

The extremely low power device sends signals at radio frequencies that are picked up by satellites in low Earth orbit. It was developed by Dutch company Plant-e and Lacuna Space, which is based in the Netherlands and the UK, under ESA’s programme of Advanced Research in Telecommunications Systems (ARTES).[]

The eccentric engineer: a tale of six pips and how the BBC became the national arbiter of time (Engineering and Technology)

This edition of Eccentric Engineer tells the story of the BBC Time Signal and how, over the years, it has just got more complicated.

Every engineer needs to know the time, if only so as to not miss lunch. Since 1924, many Britons have been checking their watches against the BBC time signal, known affectionately as ‘the pips’.

The history of the ‘pips’ is almost as long as the history of the BBC itself. The first transmissions from what was then the British Broadcasting Company began in late 1922 and soon afterwards there were suggestions of broadcasting a time signal under the control of the Royal Observatory at Greenwich – then the arbiter of time in the UK.

No one seems to have seen a need for this degree of precision, but early broadcasts did use their own ad hoc ‘pips’, marking the 8pm and 9pm news programmes with a time signal consisting of the announcer playing the Westminster chimes on a piano and later a set of tubular bells. This proved rather popular with listeners, who could now adjust their clocks and watches daily, so the BBC decided to invest in some more high-tech clocks from the Synchronome Company. These provided audible ‘ticks’, which the announcer then simply counted down.[]

What Is Replacing Shortwave? (Radio World)

A joint effort is necessary to bring the digitization of radio to a successful end

Analog shortwave will celebrate about 100 years of existence in 2028 when many hope 5G will have been properly defined, tested and applied, though broadcasting is low on its long list of perceived advantages.

It’s true that shortwave was typically a medium of the Cold War that peaked in 1989 and that afterward its listenership dwindled. Many international broadcasters gave up on it as the post-war transmitters got rustier and the energy bills kept mounting.

After all, when budget cuts are needed, no transmitter will go on strike or write to the press, as happened when the BBC World Service tried to unsuccessfully close its Hindi shortwave transmissions in 2011. In 2020 these broadcasts stopped, when committed BBC Indian listeners, writers and thinkers who opposed it in 2011 did not protest too much.

The slow death of shortwave has been blamed on the internet and satellite. As technology and content are inextricably linked, shortwave created its type of content that is no longer favored by the savvy FM listener, internet user and cellphone obsessed.[]

Filter Basics: Stop, Block and Roll(off) (Nuts and Volts)

A casual observer might think that wireless systems consist primarily of filters connected by the occasional bit of circuit! Block diagrams of transceivers often include as many filters as any other function. This is true at the system level, just as it is at the circuit level — and many circuits behave in a filter-like way, whether intended to be a filter or not! That makes understanding filter basics important for wireless success.[]


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Scott Tilley (VE7TIL): The Amateur Astronomer Who Found a Lost NASA Satellite

Many thanks to SWLing Post contributor, Cap Tux, who shared a link to the following video on YouTube. This short video is brilliant and will be the reference I use when people ask about the intersection of radio and amateur astronomy:

Click here to view on YouTube.

Amateur astronomer Scott Tilley made international headlines when he rediscovered NASA’s IMAGE satellite 13 years after it mysteriously disappeared. In this interview with Freethink, Scott discusses his role in the satellite’s recovery, why he enjoys amateur astronomy, and how citizen scientists like him have contributed to our knowledge of space from the space race to the present day.

And I personally think our Post friend, Troy Riedel–who is an avid amateur astronomer–should start tracking satellites! (We’ll see if he’s reading this post!)

I’m curious: are there any Post readers who are into the satellite tracking side of amateur astronomy?

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First Amateur Radio in Geosynchronous Orbit Will Aid Disaster Communications

GreenBankTelescopeCould it be we will have a true geosynchronous satellite for Amateurs in 2017?! I hope so, and we will not need an antenna this big to use it!

This was first reported in Wireless Design Magazine

Researchers at the Ted and Karyn Hume Center for National Security and Technology are preparing to send an amateur radio transponder into a geosynchronous orbit in 2017.

“Seven days a week, 24 hours a day, 365 days a year, a new ham band will be available for the Americas,” said Robert McGwier, a research professor in the Bradley Department of Electrical and Computer Engineering and the Hume Center’s director of research. “It will allow rapid deployment to disaster areas and support long-haul communications for first responders.”

This would be the first amateur or “ham” radio payload in a geosynchronous orbit, and would significantly enhance communications capabilities for amateur radio operators, in particular following natural disasters or other emergency situations. The Hume Center team met with Federal Emergency Management Agency Administrator Craig Fugate in September to discuss the project.

The full article may be found following this link.

I have really been enjoying trying to catch the satellites and the International Space Station as I am able, but it really is catch as catch can due to orbiting times and changing horizon points. A geosynchronous orbit satellite means we could plant an antenna pointed directly at the satellite and find it there day or night. I for one am ready!! I might even dedicate an inexpensive dual-band radio to it assuming typical satellite repeater protocol is used.

I will post more details as I find out additional information.  Cheers! Robert

Robert Gulley, AK3Q, is the author of this post and a regular contributor to the SWLing Post. Robert also blogs at All Things Radio.

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