Category: Category: Designs

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). In our conditions, a 80 cm satellite parabola is a reasonable minimum when it comes to the receiving antenna. I still had to do an […]

HF5L Remote

The HF5L station has been adapted for remote access via an internet connection. HF5L Remote is initially intended for standard contacts in the 3.5 and 7 MHz bands. HF5L Remote is currently a 100 W low-power station. It is equipped with a Yaesu FT-897 transceiver with an external AT-897 antenna box, as well as a […]

SP9VFD antenna system for EME

EME communications have fascinated Rafał SP9VFD from the very beginning of his amateur radio hobby, ie since 1991, when he received the first license at the age of 15. At the time, his favorite reading was UHF guide  “Poradnik Ultrakrótkofalowca”  by SP6LB. However, it was only in 2007 that he managed to carry out the […]

GNI-r6 controller for RAS, SPX AZ/EL and BIG-RAS azimuth/elvation rotators

A new rotator controller model is available for rotating VHF antennas in azimuth and elevation. Below is a quick guide for the GNI-r6 antenna rotator controller. Introduction. The GNI-r6 controller supports one dual rotor with DC motors for azimuth and elevation rotation that has pulse outputs (pulser or reed switch). Antenna rotation is possible with […]

DX from space

Amateur telemetry reception from ARTSAT2 interplanet probes: DESPATCH and Shin-en2. Authors: Piotr SP5ULN, Michał SQ5KTM, Piotr SP5MG, Łukasz SQ5RWU. Introduction Bands above 50MHz are often treated only as local FM communication channels. Here and there in the radioamateur environment, the opinion is repeated that in this frequency domain nothing particularly interesting is happening, excluding only […]

Polish student satellite PW-SAT2 transmits

We live in interesting times. In orbit is the Polish student satellite PW-SAT2 which broadcasts data in our radio-amateur band of 70cm. The history of the PW-SAT2 project is also described in Wikipedia and on the website of the Student Astronautical Circle. There is also an interesting photo gallery from the implementation of the PW-SAT2 […]

QCX transceiver QRP CW

I have been interested in QRP solutions for a long time. Of course, I do not avoid QRO, which like QRP gives me pleasure. Long time ago I built TRX Libra on the 80-meter range, unfortunately I did not have the desire to fully run it. Now I have found a very interesting and modern […]

CHA-250B antenna by SP5GNI

Based on the best experiences found on the web, I made my own copy of the CHA-250B antenna. This antenna has many controversial opinions. I decided to do it because having a Hex-beam directional antenna and SDR radio – I needed a multi-band antenna with omnidirectional characteristics. In addition to the characteristics, the most important […]

How to measure the performance of the HF receiver?

In the comment to “HF5L Radio Club in SSB Fieldday 2018” Marek SP5IXS rightly pointed out that “third order dynamic range is a key parameter”. He also asked good questions: What is the difference between IP3 and “3rd order dynamic range”? What is the relationship between RX sensitivity and “3rd order dynamic range”? As for […]