VO-52 Transponder Activation Postponed



It had been hoped that the amateur radio SSB/CW satellite HAMSAT (VO-52) would be reactivated on Thursday, March 8 but this has now been postponed.

More time is needed to carry out observations on the state of the satellite, which fell silent Feb. 28, so the activation has been put back by at least a week.

HAMSAT (VO-52) carries two linear transponders for SSB/CW operation. It had been using the Indian transponder but when it is switched back on it will use the Dutch transponder built by William Leijenaar PE1RAH. 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

Working 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/

HAMSAT VO-52 Falls Silent



The amateur radio satellite HAMSAT VO-52 ceased operating on February 28, neither it’s beacon or 435/145 MHz SSB/CW linear transponder have been heard since.

Ib Christoffersen OZ1MY reported that he heard and briefly used the transponder on the pass with Acquisition of Signal (AOS)  in Copenhagen at 0826 UT on February 28. On the next pass with AOS at 1003 UT it was not on.

Mani VU2WMY provides this update:

Dear HAMSAT VO-52 users,

With regrets, we confirm the non-availability of the transponder on HAMSAT VO-52 since 28th February 2012. This is the first ever interruption in the services of HAMSAT since 5th May 2005.

The timely feed back from John K8YSE, Domenico I8CVS, Eugenio IZ8JHD, Jan PE0SAT and Nitin VU3TYG were highly appreciated and acknowledged by the ISRO’s HAMSAT Mission Management Board.

I’m herewith enclosing the mail received from Mr. T.Parimalarangan, Operations Director-HAMSAT VO-52 regarding the ‘Temporary Non-availability’ of VO-52 transponder and beacon.
Mr. Subramani VU2WMY:

Thanks for obtaining the user feedback. You may please post the following message in the Users website. If possible, try to find out who has last operated HAMSAT payload transponder on 28th and at what time

“HAMSAT Transponder services not available temporarily due to operational reasons. Inconvenience regretted”

With Best Regards,

Ph:  080 – 2202 9011 (O)
080 – 2535 0132 (R)
0 – 9480333563 (M)
080 – 2202 9062

AMSAT-India Linear Transponder

AMSAT-India 435-145 MHz Linear Transponder

AMSAT-India 435/145 MHz Linear Transponder

At Hamfest India (HFI) 2011, held in Kochi Dec 10-11, a presentation was given on a new Indian linear transponder and a CubeSat communications system.

This was the largest gathering of radio amateurs in India so far. Radio Amateurs and SWLs from all over the country and invited guests from other countries enjoyed the two-day event.

AMSAT-India gave several presentations at the event, among them was one by Ganesan Namachivayam KJ6LRR in which he described a satellite 435/145 MHz linear transponder with a bandwidth of 50 kHz and capable of 1-3 watts PEP output. AMSAT-India plan to develop a smaller linear transponder for CubeSats.

AMSAT-India CubeSat

AMSAT-India CubeSat

Ganesan also described a CubeSat communications system comprising a 435 MHz half-duplex narrow‐band FM transceiver supporting a data rate of 1200-9600 bps. The transmitter produces 1 watt output and can also operate as a Morse Code beacon.

Other presentations included:

  • Real Time Tracking by Mani VU2WMY
  • Working with LEO Sats by Dr. Raveendranath VU2RVJ
  • Telemetry Decoding by Nitin VU3TYG

The slides from the AMSAT-India presentations are at

Hamfest India (HFI) 2011 http://www.hamfestindia2011.com/

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