Author Archives: m0xtd

Mar 14 2012

How to work the SSB amateur radio satellites such as VO-52

The SSB/CW linear transponder amateur radio satellites such as VO-52 are great fun to work but the technique required is different to that used for the FM satellites.

Simon 2E0HTS has produced a video showing how to make contacts through VO-52.

Using a home-made 10 element 435 and IO Loop for 145MHz, with a Yaesu FT-847. Simon – 2E0HTS, adjusts his (uplink) transmitted signal to correct the Doppler of the received (downlink) frequency whilst talking to fellow Ham operators around Europe. Thanks to the stations worked via the VO-52 satellite which were SP9FPP, PD0HF & SP6DCO.

Watch How To Make A VO-52 SAT QSO

Most linear satellites use what are known as ‘Inverting Transponders’ to reduce the Doppler shift. You transmit lower sideband (LSB) on the uplink and it appears as upper sideband (USB) on the downlink.

When working through linear transponders use as little power as possible, this will help extend the lifetime of the transponder and satellite batteries. As a guide ensure your downlink signal is no stronger than the satellite beacon. Low duty cycle modes such as SSB and CW are recommended.

The band plan for linear satellite downlinks is similar to what you’d expect on the HF bands with CW operation in the lower part of the downlink and SSB in the rest. Current satellite status can be seen at http://oscar.dcarr.org/

Since this video was made VO-52 has changed over to its Dutch SSB/CW transponder and now uses these frequencies:
Uplink:         435.2250 – 435.2750 MHz SSB/CW
Downlink:     145.9250 – 145.8750 MHz SSB/CW
Beacon:       145.8600 MHz CW

John Heath G7HIA wrote about operating through VO-52 in his article ‘Getting started on amateur radio satellites’ that was published by the Radio Society of Great Britain in the March 2007 edition of RadCom. Download the article at https://amsat-uk.org/wp-content/uploads/2011/05/satellites_radcom_mar07.pdf
Copyright 2007 Radio Society of Great Britain. For personal use only – no copying, reprinting or distribution without written permission from the RSGB.

David A Palmer, KB5WIA, has written an article “Twins!  A Backpack-Portable Full Duplex Satellite Station with Dual FT-817ND’s” that can be seen at http://kb5wia.blogspot.com/2010/10/satellite-portable-station.html

SimpleSatLookDown satellite tracking software http://www.uk.amsat.org/?p=8217

Mar 14 2012

Amateur Radio CubeSat Masat-1 Takes First Pictures

Masat-1 image 08 taken 12:37 March 8, 2012

Masat-1 image 08 of Southern Africa taken 12:37 March 8, 2012

Masat-1, the first Hungarian Satellite made history again when it captured the first satellite space photographs on March 8, 2012. The first photo showed the southern section of the African continent. The next photos were made of Australia and Antarctica, in a quality and quantity unprecedented in the CubeSat realm.

Besides their sole beauty, these photos also demonstrate the careful planning and execution of the satellite’s operation, proving that even within the tight mass and energy constraints of Masat-1 it is possible to capture space images.

Masat-1 image 09

Masat-1 image 09 taken 12:37 March 8, 2012

Masat-1 is the first Hungarian satellite, designed and built by students and lecturers of the Faculty of Electrical Engineering at the Budapest University of Technology and Economics in cooperation with the Hungarian Space Office and various domestic companies. The satellite, measuring 10x10x10 cm and weighting 1 kg, was launched by the Vega launch vehicle of the European Space Agency (ESA) from the spaceport at Kourou in the Caribbean. Masat-1 along with seven other student built amateur radio satellites were deployed into a 1441 by 310 km orbit.

The satellite has been operating flawlessly since the launch of February 13, 2012, steadily transmitting data to the primary ground control station (Budapest University of Technology) and the secondary ground control station (Érd, Hungary). In addition to these domestic control stations, more than 120 radio amateurs have received the satellite worldwide. Their total contribution to the success of the mission exceeds 200 000 data packets.

Masat-1 image 19 taken 05:53 March 12, 2012

The on-board camera of Masat-1 has a mass of about two Euro coins. The maximal resolution is 640×480 pixels. A width of 1 pixel corresponds to a distance of 1 to 10 kilometres on the photos recorded.

The call sign of Masat-1 is HA5MASAT and the telemetry transmission frequency is  437.345 MHz +/- Doppler shift, which at worst case could be +/- 10 kHz.

The Masat-1 Ground Station Client Software was prepared to process the GFSK 625/1250 bps transmission received from the satellite Masat-1. The software provides the following functions:

– Audio demodulation
– Packet decoding
– Packet data visualization
– Frequency waterfall plot to aid radio tuning

Download the software and a test WAV file from http://cubesat.bme.hu/en/foldi-allomas/kliens-szoftver/

Further pictures can be seen at http://cubesat.bme.hu/en/2012/03/14/a-masat-1-elkeszitette-az-elsu-urfelveteleket/

English language press release http://cubesat.bme.hu/data/sajtokozlemeny/masat-1_sajtokozlemeny_20120314_en.pdf

Masat-1 designated MagyarSat-OSCAR-72 (MO-72) http://www.uk.amsat.org/4928

Mar 14 2012

AMSAT-India Thanks You

Dear Friends,

I take this opportunity to sincerely thank each and every user and well wishers, who have been following and monitoring closely all those events and activities that followed since the interruption on 28th February 2012.

Thanks for all those encouraging and supporting expressions!

VO-52 on FUNcube Dongle by Dave G4DPZ

VO-52 received on an AMSAT-UK FUNcube Dongle by Dave Johnson G4DPZ 17:27 pass on March 14, 2012

The initial telemetry reports indicated all the crucial and critical parameters to be normal and satisfactory and we do hope ‘HAMSAT VO-52’ would be available with much stronger power. The overall spacecraft health is in ‘Excellent Condition’ and all that we need to do is to monitor the transponder parameters.

14:05 UT on 14 March was a moment of great satisfaction and joy to all of us here in bringing ‘HAMSAT VO-52’back to life. It also gives us great pleasure to note that ‘HAMSAT VO-52’from India/ISRO has a earned a name in the history of ‘Amateur Radio Satellites’.

On behalf of everyone, I take this opportunity to sincerely thank particularly, Mr. Parimalarangan-Operations Director for his hard work and great efforts besides his exemplary technical competence and skills exhibited in recovering back ‘HAMSAT VO-52’.

Also my sincere thanks to Mission Director Mr. R. Suresh and the entire ‘HAMSAT VO-52’ Mission Management and Project teams for all the support, encouragement and recognition provided to ‘Amateur Radio World’.

My Good wishes to VO-52 and the transponders on-board for a ‘Healthy and Long Life’.

My Good wishes & Greetings, once again to William PE1RAH.

73

Mani, VU2WMY
Secretary & Station-In-Charge
Upagrah Amateur Radio Club VU2URC
ISRO Satellite Centre
HAL Airport Road, Bangalore-560 017.
Phone:(O)91-80-25082054/2598/2192
Mobile:  91-80-98803 41456
E-mail ID: wmy@isac.gov.in
vu2wmy_mani@yahoo.com
isrohams@yahoo.com

The new HAMSAT (VO-52) frequencies are:

Uplink:         435.2250 – 435.2750 MHz SSB/CW
Downlink:     145.9250 – 145.8750 MHz SSB/CW
Beacon:       145.8600 MHz CW

How to work the SSB satellites http://www.uk.amsat.org/2712

HAMSAT VO-52 Dutch Transponder Activated http://www.uk.amsat.org/5755

HAMSAT VO-52 Activation Planned For Wednesday http://www.uk.amsat.org/5685

HAMSAT VO-52 Falls Silent http://www.uk.amsat.org/5217

AMSAT Bulletin Board (AMSAT-BB) http://www.amsat.org/amsat-new/tools/maillist/

Mar 14 2012

HAMSAT VO-52 Dutch Transponder Activated

VO-52 on FUNcube Dongle by Dave G4DPZ

VO-52 received on an AMSAT-UK FUNcube Dongle by Dave Johnson G4DPZ during the 17:27 pass on March 14, 2012

The Dutch SSB/CW linear transponder on the AMSAT-India amateur radio satellite HAMSAT VO-52 has been successfully activated.

Transponder # 1, which had been operating for over 6 years, fell silent on February 28 and efforts have been underway to activate transponder # 2.

Mani VU2WMY reports that the commands to ‘Turn On’ the transponder # 2 on-board HAMSAT VO-52 were successfully sent on March 14 during the 1400 UT 35 deg ascending Node pass over Bangalore, India.

The commands were successful and the CW message beacon of the Dutch transponder # 2, built by William Leijenaar PE1RAH, was heard in Bangalore loud and clear, some 6 years and 4 months since it was last switched on.

The Dutch SSB/CW transponder uses these frequencies:
Uplink:         435.2250 – 435.2750 MHz SSB/CW
Downlink:     145.9250 – 145.8750 MHz SSB/CW
Beacon:       145.8600 MHz CW

When working through linear transponder satellites such as VO-52 use as little power as possible, this will help extend the lifetime of the transponder and satellite batteries. As a guide ensure your downlink signal is no stronger than the satellite beacon. Low duty cycle modes such as SSB and CW are recommended.

How to work the SSB satellites such as VO-52 http://www.uk.amsat.org/2712

AMSAT-India Thanks You http://www.uk.amsat.org/5777

HAMSAT VO-52 Activation Planned For Wednesday http://www.uk.amsat.org/5685

HAMSAT VO-52 Falls Silent http://www.uk.amsat.org/5217

Leijenaar Electronics http://www.leijenaarelectronics.nl/

AMSAT-India http://www.amsatindia.org/

Mar 14 2012

HAMSAT VO-52 Activation Planned For Wednesday

HAMSAT VO-52

HAMSAT VO-52

Mani VU2WMY reports that due to ‘Operational Constraints’ the commands to turn on the Dutch SSB/CW transponder on HAMSAT (VO-52) could not be sent on Tuesday and attempts at 01:44 UT and 03:20 UT Wednesday were unsuccessful.

The next attempt will be made during the 14:00 UT pass over India.

William Leijenaar PE1RAH, designer and builder of the Dutch SSB/CW linear transponder on HAMSAT (VO-52), requests reports when the transponder is activated. He says:

! ! !  Please don’t use high uplink powers !!! (We don’t want it to rise temperature very fast just after cold switch on) ! ! !

Please listen for the CW beacon at 145.860, which is a good reference.
(Audio records and reports are very welcome at ISRO and myself)

73 de PE1RAH,
William Leijenaar

The frequencies used will be:

Uplink:         435.2250 – 435.2750 MHz SSB/CW
Downlink:     145.9250 – 145.8750 MHz SSB/CW
Beacon:       145.8600 MHz CW

How to work the SSB satellites http://www.uk.amsat.org/2712

HAMSAT VO-52 Falls Silent http://www.uk.amsat.org/5217

Leijenaar Electronics http://www.leijenaarelectronics.nl/

AMSAT-India http://www.amsatindia.org/

Mar 13 2012

New Amateur Satellite Frequency Coordination Request Form

Hans van de Groenendaal ZS6AKV

Hans van de Groenendaal ZS6AKV

IARU Satellite Advisor Hans van de Groenendaal ZS6AKV has made available a new version of the Amateur Satellite Frequency Coordination request form.

Frequency coordination for amateur radio satellites is provided by the IARU through its Satellite Advisor, an official appointed by the IARU Administrative Council, its top policymaking body.

The IARU Satellite Advisor is assisted by an Advisory Panel of qualified amateurs from all three IARU Regions. The panel meets regularly via Skype to consider amateur satellite frequency coordination requests for satellites planned for operation on frequencies in the amateur service. The panel members often provide advice and assist satellite builders with the selection of   the best possible frequencies to meet the objectives of their mission.

The Amateur Satellite Frequency Coordination request form has been updated (Version 27) and is available for download from http://www.iaru.org/satellite.

On the IARU web satellite page there are also available a number of guideline documents which will assist satellite builders, including a document on the ITU requirements for Amateur Radio Satellites.

73

Hans van de Groenendaal ZS6AKV
IARU Satellite Advisor

A list of coordinated amateur radio satellites can be found at http://www.amsat.org.uk/iaru