Tiny GS Project

A couple of months ago, I came across a magazine article in my monthly amateur radio magazine about the TinyGS project.

The TinyGS project  consists of several  nano-satellites that are in low Earth orbit. These satellites have been launched by several entities, including universities, foundations and other entities worldwide for experimental purposes.

The TinyGS satellites are very small (about 12” x 12” x 12”) and consist of a low powered radio transceiver, rechargeable batteries and solar panels to recharge the batteries. They are very low cost to build and relatively simple compared to most satellites.

Typical TinyGS satellite

The TinyGS satellite network is mostly designed for amateur radio operators, students and experimenters. There are currently about  a dozen of these satellites currently in low earth orbit with more being deployed fairly frequently. What I find intriguing is the range that these satellites have to send and receive signals considering their relatively low radio power output. Most of the satellites only have about one watt of transmitter power but are able to send messages that can be received up to 5,000 km away. Considering that the average cell phone has about one half of a watt of transmitting power and is limited to about five miles of range, this is amazing. The key behind the method that the satellites send and receive signals is that instead of broadcasting a standard FM radio signal (like a cell phone does), the satellites send and receive digital data “packets” at a relative low speed. Added to that is the fact that the satellites are usually in “line of sight” with the receiving station on Earth so there are few or no obstacles in the way to impede the signal.


Enrolling in the TinyGS network is free and consists of a mini-web site for each user. The mini- web site shows a map of your station’s location, details about you station, an interactive map of the world showing where the satellites are in their current orbit along with a bunch of other cool information. If you want to enroll in the project, navigate to www.tinygs.com

 Have a look at one of my stations at this URL: https://tinygs.com/station/KM6TIN_@6110445856

(feel free to click on everything to see what the various icons do--almost every little icon or pic does *something*.)

This antenna is called a Quadrifilar Helix Antenna. The main advantage of this type of antenna is that it is omni-directional, so it doesn’t matter much where the satellite is in the sky to receive the beacon signal. I built several different versions of this type of antenna with various degrees of success. Still, I felt that I could do better.

It turns out that this is very inexpensive hobby to get in to. One can purchase the small transceiver needed to capture the satellite packets (~$25.00). The only other two things you need are a computer (Windows, Linux or Apple) and an antenna which can be purchased or home-made.

 Next, I tried a completely different design called an “Inverted V Dipole”. The Inverted V is similar to “Rabbit Ears” that old school televisions used to use with the exception that the antenna is facing horizontally instead of vertically. I found that with this design, I was able to acquire satellite transmissions at a much great distance than with the Helix style antenna but this style of antenna is not omni-directional, so pointing the antenna towards the satellite’s path becomes more critical.

I used a 3D printer to make the base fixture for this antenna and the antenna elements are made out of straightened coathangers which are "tuned" to the approprate length wavelength (approx.17 inches each).


Although this antenna is more sensitive to the satellite’s location in the sky, it is much more sensitive to the the signal.

So far, the most distant signal I have received with this design is an astounding 6712 km distant (4176 miles)!

The satellite the signal was received from only has one watt of transmitting power (about twice as much power as the average cell phone)  which has a range of about five miles.


The secret to achieving such long distance communications with such low transmitting power is in the way the data is broadcast. Instead of using Amplitude Modulation (AM) or Frequency Modulation (FM) or some other conventional method of broadcasting a radio signal , the signals are sent in a digital “packet” format. The packets are sent at a relatively low speed and because of the nature of them, they can travel extremely long distances provided the receiver location is in “line-of-sight” more or less.


I’ve been experimenting with different antenna designs using copper wire and straightened coat hangers. I use a 3D printer to create a fixture for whatever type of design I’ll be building.

Shown below are a few of the different antenna if built over the last few months. Some work better than others...

If you decide to join in this fun hobby, here are a couple of words of advice. Although Amazon sells these devices, the ones that  are offered transmit and receive on the different frequencies than those that are used for the TinyGS satellites. Additionally, there are a few different manufacturers that make the devices. The only on-line resource I have been able to find for the devices is from Alibaba.com, with the superior product being the device manufactured by “LilyGo” as shown above. Be sure to purchase the unit that operates in the 433Mhz band. Here is a link to the device that I am currently using: LiliyGo LoRa32

It’s possible to transmit signals to the satellites which will be stored in the the satellite’s “payload”, although I have not attempted that yet.


More to come...

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