GreenCube is aimed at demonstrating an autonomous biological laboratory for plants cultivation on-board a CubeSat platform. The satellite project is managed by the S5Lab research team at Sapienza University of Rome https://www.s5lab.space/index.php/greencube-home/. The spacecraft has been launched on 13 July 2022 and it has been deployed in Medium Earth Orbit (MEO) at approximately 6000 km […]
Category: Designs
What’s the deal with this M17?
Many have heard of it, but few know what it is about. And it’s worth knowing. The M17 project is often called the future of digital radio in the global amateur radio community. For Poles, it is a reason to be proud, because the idea was created at the turn of 2018 and 2019 in […]
Our satellite activity
After a series of meetings on VHF subjects in our HF5L club, we started to prepare for work through amateur satellites. March 8, 2019 Piotr SQ5JUP made the first contact from home QTH via FOX-1D satellite (AO-92) on FM using the X300 antenna + duplexer MX-72A + IC-9100. As you can see, you can do […]
Electret microphone instead of dynamic and vice versa
Some transceivers have a microphone input adapted to the electret microphone and some to a dynamic one. It is not possible to replace them due to design differences. The electret microphone contains a FET transistor in the capsule, which must be supplied with DC voltage in the same wire as the audio signal. The FT-991 […]
Wireless Communication in Polish Home Army 1939-1945
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August 1 is another anniversary of the outbreak of the Warsaw Uprising in 1944, so important to all Poles. This is an excellent opportunity to present the heroic struggle of the soldiers of the Uprising in terms of military radio technology. Thanks to my colleagues SP3LD and SP3CSD, I learned about Louis Meulstee’s publications on […]
Power over coaxial cable
If a DC power supply is needed near the antennas, the use of a coaxial cable for this purpose avoids pulling the additional cable to the roof or mast. The diagram below shows the DC power inserter – Power over Coaxial (PoC) solution tested by SP5GNI. Coupling capacitors should allow the transfer of relatively high […]
Wireless antenna switching
Automatic antenna switching is a convenience and safer operation of the equipment, but it does not solve all the nuisances. If the antenna switch is located in the radio room, then a separate fider should be derived from each antenna, which does not have a very favorable effect on costs and aesthetics (not to mention […]
GNI-r5 controller for RAU, RAK, BIG-RAK and RAEL rotators
Rotary antenna rotator controller. A new model of the GNI-r5 antenna rotator controller is available. Compared to previous versions, it has new features and a new steel casing. The following is the shorted operating manual for the GNI-r5 antenna rotor controller. Introduction. The GNI-r5 controller supports one rotor with pulse […]
Es’hail-2 (or QO-100) for beginners
I bought a 80 cm satellite dish (16 Euro), a converter (4 Euro), installed it on the roof and set it up on the satellite (Dish Pointer was very helpful for azimuth and elevation finding). In our conditions, a 80 cm satellite parabola is a reasonable minimum when it comes to the receiving antenna. I […]
ADALM-PLUTO clocker
In the post “ADALM-PLUTO development kit for (not only) Es’hail-2 satellite”, the topic of the 40 MHz clock generator for Adalm-Pluto and 25 MHz for the LNB satellite converter was considered. The problem of the 40 MHz clock generator is somewhat solved by replacing the original micro-module of the generator with a more stable one, […]