Categories
Ham Satellite news

Two new digipeating satellites coordinated

ROM-3

According to IARU two new satellites, Veronica and ROM-3, has been coordinated and are planned to launch during 2023. Following are info from ANS-218:

Veronika
From the Technical University of Kosice, Veronika is a 1U CubeSat scheduled for launch on a Falcon 9 launcher on the Transporter 9 mission in October 2023. The satellite will be equipped with a 24/7 digipeater on two different bands, as well as experimental SSDV transmissions.

The satellite also has an education and outreach mission in that it is planned to involve Slovak grammar and high schools and to transmit special CW and AX.25 messages on several special occasions. From a platform perspective, the satellite will be equipped with a novel ADCS subsystem, including electromagnetic actuators and a GNSS receiver. This will also help to identify the satellite during the first days and weeks. The satellite will communicate o using Spacemanic’s well-known Murgas transceivers (BDSat-1, BDSat-2, Planetum-1).

Altogether, Veronika will provide: AX.25 telemetry; a CW beacon; a digipeater; AX.25 & CW messages on special occasions for community engagement; Experimental SSDV transmissions; and SATNOGS integration, decoder and dashboard. A downlink on 436.680 MHz has been coordinated and will use 9k6 G3RUH AX.25 and a CW beacon. Planning a SpaceX launch on Transporter 9 mission in Q4 2023 to a 500/600km polar orbit . More info at https://om3ksi.tuke.sk/en/home/

ROM-3
From the Romanian Radioamateur Federation, ROM-3 is a 50 x 50 x100mm picosat with three missions and objectives. Its primary mission is to act as a digital amateur radio repeater. Its secondary mission is to transmit low-resolution SSDV images in a GFSK Mode. The tertiary mission is to transmit a CW beacon that will help amateur radio operators detect the presence of the satellite and measure basic properties of the signals such as its strength, fading due to spin, Doppler to measure speed, etc. A downlink on 436.235 MHz has been coordinated for 20 wpm CW, 500bps GFSK telemetry and 5kbps GFSK SSDV. Planning a SpaceX launch in October or November 2023 into a 500km polar orbit. More info at https://rom-space.ro

Categories
Antennas

3 el UHF lightweight Yagi

This 3 el UHF lightweight Yagi by RA3TOX can be built with low cost materials like 20 mm PVC tube and tube holders as element holders. The element can be made of 3.2 mm aluminium welding rods. Making a second yagi on the same boom and it becomes a X-yagi, with correct made phasing cables.

I have built one X-yagi version and tests on the ground (see picture above) was very good, when I tested it as a SatNOGS antenna. Unfortunately, something broke when I mounted it on the mast so it is not in use.

The driven element (loop type) was kind of hard to get correct, I made several versions before I got the correct SWR for 436 MHz.

This is the drawing I used:

  • Original drawings, calculator and design by RA3TOX
  • Used by PE0SAT for his SatNOGS station. Link here.
Categories
Ham Satellite news

LEDSAT AX.25 digipeater

LEDSAT is a 1U CubeSat by Sapienza University of Rome (S5Lab research team) and University of Michigan. It has the same AX.25 digipeater function as IO-117 (Greencube).

It has a very strong downlink and good RX ears. This is the frequency I has been using (+/- doppler):
TX (Uplink): 435.3087 MHz
RX (Downlink): 435.1885 MHz

I succeeded digipeating with the lowest power settings on the IC-9700 at 5 degree elevation.

Greencube Terminal by OZ9AAR is the recommended terminal software.

Categories
Telemetry

Nayif-1 EO-88 last decode over Stockholm

This was the last decode from me over Stockholm at aprox 1105UTC 18:th July.

Categories
Telemetry

Nayif-1 EO-88 2023-07-16 1900UTC

Altitude 240 km over Stockholm, still going strong!

Categories
Telemetry

Nayif-1 EO-88 2023-07-14 0910UTC

Altitude 253 km over Stockholm