SUMBANDILASAT  RETURNS TO OPERATION SLOWLY

17 July 2010 times UTC 

South Africa
06:19
07:53

 Europe
0909
1043
1820
1954

The ground control station  will start slowly with the amateur payload and observe if the satellite remains stable and then gradually add more.

With recent changes in software please note the following operating procedure.

The PTT of the transmitter now STAYS ON for the duration of the payload activation (i.e. 15 min), regardless of a valid “transponder” tone received.  Note that this does not get rid of the “cut-off” problem, nor of the requirement to embed a valid tone when you want to use the payload – see detailed explanation below. 

The following example depicts the ideal usage scenario of the payload:

1. As the satellite comes over the horizon, an unmodulated carrier (“quieting”) will be received by all on UHF

2. Person A starts to transmit on VHF (with valid “transponding” tone embedded in the transmission) and the transmission is relayed on UHF

3. When Person A releases his/her PTT, the satellite will continue to transmit what it is receiving (usually this will be “noise”) for a further ±3s.  Nobody should start to transmit during this time!

4.0 At the end of the ±3s period, everybody will again hear the unmodulated carrier.

5. NB: only when this unmodulated carrier is heard should Person B start to transmit.  Listen to this mp3 recording as an example of valid usage HERE

In simple repeater operation terms , leave a 3 second gap between overs.

SA AMSAT ELECTS OFFICE BEARERS

President
Dave Long ZS5FR

Vice President                     
Eddie Leighton ZS6BNE

Secretary/Treasurer            
Hans van de Groenendaal ZS6AKV

Technology Manager         
John Willescroft

SAARDT Representative  
Craig Gibson ZS6CG

Committee members         
Laurie Devereux ZS5D
Eddie Leighton ZS6BNE
Dave Smith ZS5LPT
Allan Saul ZS1LS

Regional Organisers
ZS6 , ZS4,ZS3                     
Eddie Leighton ZS6BNE
ZS5 
Dave Smith ZS5PLT
ZS1, ZS2                              
Allan Saul ZS1LS

SA RADIO AMATEURS TO TAKE TECHNOLOGY INTO SPACE

South African Radio Amateurs are set to join other amateur and university groups in the world to build and launch their own CubeSat. This was announced in a presentation at the recently held SA AMSAT Space Symposium in Durban. Read  full story here

JOIN SA AMSAT NOW

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Members also receive a membership certificate upon joining. If you are already a member and have not received a certificate please send your details to saamsat@intekom.co.za and a certificate will be mailed to you.

To join, get all the details here 

SATELLITES FOR BEGINNERS WITH

DAVE LONG ZS5FR

Download the PowerPoint Presentation here in PDF

Download article in word here

Download audio presentation here