Working Satellite SO-67 on Flea Power!

My profound thanks to John. K8YSE, for posting the recordings he's made of passes over North America of the new South African amateur satellite, SO-67. His recording, which he began at 15:00:38 UTC on 15 November, provides proof that - even amid the chaos of a pass like that one - very low power levels can work our amateur satellites.<O></O>
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Here is a link to that recording:<O></O>
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http://www.papays.com/SO-67_15Nov2009_150038z.mp3<O></O>
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Anyone who listens to the recording will hear the weak-signal call of N3TL at 8:51 into the recording. I'm faint, but I'm in there ... on 50mW (.05 watt) from my Yaesu VX-7R HT and Elk dual-band log periodic antenna. <O></O>
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KI0G surprised the heck out of me when I heard him call me several seconds later. When he did, I thought, "He must be calling me blind. There's no way I made it through on 50 milliwatts."

I was wrong. K8YSE's recording shows that my signal made it into SO-67 beginning at 15:09:29 UTC and ending at 15:09:30 UTC. According to Orbitron, one of the satellite-tracking programs I use, SO-67 was pretty much right over the intersection of 30 degrees north x 90 degrees west, or right on top of the 4-grid boundary of EM40, EM50, EL49, EL59. She was at a range of 882.050 kilometers (548.0805 miles) to my handheld station in EM84 at 15:09:30 UTC. Based on those distances, my power level translates to 17,641 kilometers (10,961.61 miles) per watt. Given how busy SO-67 passes over North America have been, I'll take that!
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Thank you, everyone at AMSAT-South Africa, for building, launching and orbiting SO-67. She is a wonderful addition to the fleet, and one I'm proud to have worked on .05-watt.<O></O>
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73 to all,<O></O>

Tim - N3TL
Athens, Ga. - EM84ha<O></O>
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Congratulations Tim !. The SO-67 is working quite well but the chaos is due too many operators trying to get in at the same time and probably using high power in the uplink. In the next orbit to the one you are describing, I was able to operate the satellite with 1 Watt as soon as the footprint left the USA South border. Unfortunately I did not work anyone while the footprint was over Mexico. The satellite signal was strong and clean without voice cuts. In the first days of AO-51 there were similar chaos and the satellite was then set with access tone. I am convinced that SO-67 can be operated with low uplink power as long as every operator run low power and follow the AMSAT-SA instructions. Satellite QSO etiquette will help a lot too.
Best 73 and once again, congratulations !
Alex, XE1MEX

 

Amsat SO-67 Information

http://www.amsat.org/amsat-new/satellites/satInfo.php?satID=71&retURL=/satellites/status.php

 

A funny thing happened while listening to the file with media player. I have mine set to draw on the screen based on the audio heard and the attached figure was drawn and on the screen for about 5 seconds. Anyone familiar with Warner Brothers knows "That's all Folks!". I about spewed my coffee!

Thanks for the recording. Sounded like some folks had either PTT or tone problems.

 

To David, XE1MEX - thank you for the information on working SO-67 south of the border. I suspected that would be the case, and I'm thrilled to learn that you are able to get into the satellite consistently with only 1 watt. I hope to hear you on one of the satellites again soon!

To N2OBS - Thank you for posting the link to the AMSAT-NA satellite status page. That's one link I forgot to include in my original post.

To K5YU - Thank you for posting the screen shot. When you said that about eh Warner Brothers cartoons, the first thing that popped into my head was ... "Be VEWY ... VEWY ... quiet. I'm twying to work a saddawhite." HIHI

I don't believe the problem is related to either the tone or PTT problems. A ham in New Zealand posted to the AMSAT-BB email reflector over the weekend that he observed a distinct "tail" on the transponder, like one you'd hear on a terrestrial repeater. He worked two passes of the satellite, and he repoted that each had less than 10 operators - so there was room and time for testing and observation. He said that when an operator finished transmitting, the satellite's "tail" would drop out 2-3 seconds later. Further, he said that anyone who began transmitting before the tail dropped out would, themselves, drop out with it.

If you listen to the recording again, what you hear corresponds to that. In fact, I beleive I used that to my advantage to get in on .05-watt. As the pass unfolded, I simply waiting until someone transmitted right after another finished. In just a couple seconds they would drop out because the tail dropped - and that's when I transmitted. At that moment, I knew that no one else "had" the transponder, so I at least had a chance to get in there. And it worked ... hihi.

73 to all,

Tim - N3TL

 

Hi Tim,

I have nothing really relevant to add to this discussion, except -- "Hey neighbor!" I'm in Athens as well. Sometime soon I plan on 'working the birds'.

All the best, and congratulations!!
--Alex / KF4YOR

 

Hey Alex,

Thanks for your note - and congrats on getting the new antenna up! I saw the posts on the club's Yahoo group. I look forward to working you on the satellites soon!

Tim

 

Squelch tail

I read the N3TL post about the SO-67 squelch tail possibly causing transmissions to cut out. Seems like that would be an on-going problem.

Regards,
-Mel

 

Once the primary payload is commisioned, they can go back and rewrite the software for the amateur repeater. I saw this in an email from one of the project leaders in South Africa.

73, Drew KO4MA

 

Hey Drew,

Thanks for the information about the software. In my case, I believe that tail actually helped me get through on flea power - I timed my transmission to coincide with the dropouts.because I knew the transponder wasn't active at those moments.

73,

Tim

 

HO-68 SATELLITE

[COLOR="Blue"]hi guys
am i right in understanding that HO-68 carries a D-STAR repeater
if so has any station worked this mode ?
thanks M3PQQ robert[/COLOR]