Amateur radio, space, technology and other geeky stuff by Alexandru Csete
A few months ago I started looking at various options for omnidirectional antennas with circular polarization for satellite communications. I came across the TA-1 137 MHz turnstile antenna from Wimo, which looked like an interesting option for a reasonable price.
Continue reading “On-air tests of the Wimo TA-1 turnstile antenna”
Today we got the first storm warning of this season and so I went out to secure the DX-88 with 4 guy-wires. At the same time I did a new tuning round because I have noticed that some of the bands have moved since the last adjustment. This time I have managed to get 30 meters working.
It has now been eight years since I have retired my Hy-Gain DX-88 antenna declaring it dead for good. I was standing with a broken base element for the second time and I decided not to spend any more time and money on it but try a new antenna, a Butternut HF2V covering 160, 80, 40 and 30 meters.
Two recordings I made during the 2011 CQ WW CW contest showing how well the Butternut HF2V receives on the 21 and 28 MHz bands. The videos were recorded using the Funcube Dongle equipped with the HF converter kit and my GNU Radio based software defined radio receiver, GQRX.
Sunday, April 10, 2011 we met at OZ7SAT to start working on our antennas. The weather is becoming better and we have a few plans for upgrading the antenna farm at AMSAT OZ headquarters.
Inspired and impressed by the performance of the Funcube Dongle during my initial tests, I have decided to perform some more thorough tests using a minimalistic setup consisting of a laptop running Gpredict and Quisk SDR software, the Funcube Dongle and an Arrow II hand held satellite antenna.
Continue reading “Chasing cubesats with the Funcube Dongle and Arrow antenna”
This page collects various amateur radio satellite and cubesat receptions carried out using the Funcube Dongle. The Funcube Dongle is a small USB-flashdisk sized software defined radio receiver for 67 MHz – 1.7 GHz intended to be the ground receiver for the FUNcube satellite by AMSAT UK. It is well suited as a ground receiver for low cost space communications.
The purpose with this page is to demonstrate on the air performance of the Funcube Dongle under similar conditions that are expected for the reception of the FUNcube satellite. This page will be update regularly until complete.
The receptions below were carried out using an Arrow II hand-held satellite antenna in RF quiet areas (outside big cities).
| Satellite | Transmitter | Recordings |
|---|---|---|
| CUTE-1.7 + APD II | 437.275 MHz, 100 mW CW | Video |
| SEEDS-II | 437.485 MHz, 90 mW CW | Video |
| SWISSCUBE | 437.505 MHz, 100 mW CW / 1W FSK | Video |
| ITUPSAT-1 | 437.325 MHz, 100 mW FM CW | Video |
| BEESAT | 436.000 MHz, 100 mW CW / 500 mW GMSK | Nothing heard so far. |
| KKS-1 | 437.385 MHz, ??? mW CW | Video |
| PRISM | 437.250 MHz, 80 mW CW | Video |
| FO-29 | 435.795 MHz, 100 mW CW | Video |
| VO-52 | 145.860 MHz, 1W SSB/CW | |
| HO-68 | 435.790 MHz, 200mW CW | Video |
| AO-51 | 435.150 and 435.300 MHz, FM |
Other receptions carried out using standard VHF/UHF stationary beam antennas.
To be added…
I took a few photos of my Butternut HF2V vertical antenna during my winter holidays 2010/2011. You can click on the images to get higher resolution photos. Enjoy!
AMSAT OZ staff are preparing the 7 meter dish for tracking the UNITEC-1 interplanetary spacecraft.
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More than three years ago that I have mounted my Butternut HF2V multi-band vertical antenna outside and left it suffer from the windy and humid Danish climate. The settings and performance that I could achieve back then are documented in several blog posts, e.g.Tuning the Butternut HF2V.
What has happened with the Butternut HF2V since then? Well, nothing really… During these three years, the antenna has been standing and performing very well without any need for fixing or tuning it. I have done a visual inspection and tightened the guy ropes every now and then, but that’s all. In order to document it I have taken a few photos and made some SWR scans.
Continue reading “The Butternut HF2V antenna after three years”
