January 2008 - AMSAT-BB - mailman.amsat.org

AO-16 report from Copenhagen
by OZ1MY 24 Jan '08

24 Jan '08

Hi all, Tried it out this late afternoon. As someone remarked the downlink is strong - but the noise level it very high, at least here over Europe. Made a couple of QSO's on two passes. My doppler file in SatPC32 is a little different from Drews after testing the satellite: AO-16,437024.87,145920,USB,FM,NOR,0,0 It is just the downlink that is different. I am using full doppler control in the program. The downlink antenna is RHCP on this frequency - but sometimes it was better with LHCP. Have fun :-) 73 OZ1MY Ib

3 2

AO-16 Test Over Europe
by EB3SA - Carles 24 Jan '08

24 Jan '08

Hi to all The 0535 utc pass over Europe, any difficulty......... but nice ¡¡¡¡ This is my first QSO in AO-16 ¡¡ with IZ1ERR, Gracias Piero. Happy Birthday AO-16! Congratulations from Catalonia. Carles EB3SA -- Carles Roy eb3sa(a)eb3sa.com www.eb3sa.com

1 0

RFI identification
by Tony 23 Jan '08

23 Jan '08

All, I have an RFI problem that I'm trying to identify. It's a continuous pulse noise that pops on every 1/2 second. The timing between each pulse is perfect (about 0.533 seconds) and doesn't seem to change. The noise is spread accross all HF bands and on some days it seems to creep up into the 100MHz range; it's also stronger on the lower frequencies. The signal is directional and goes from almost nothing to S-8 with the antennas pointed south. The noise appeard suddenly in December and has not stopped. I have a recording and would appreciate any suggestions. Thanks, Tony -K2MO

5 5

Indoor reception of AO-16
by Bruce Robertson 23 Jan '08

23 Jan '08

We should get the word out to all those folks with all-mode, all-band radios: AO-16 may be the easiest voice-repeating satellite they'll ever hear. I've just finished listening to the 20:40UTC pass on a *really* crummy 144/440 mag-mount antenna. Fed with 6' of RG-174! Without a low noise preamp! Indoors! With the bird setting on the other side of the house!! Granted, it wasn't perfect copy, but I could have easily made many QSOs. You can hear an mp3 of this at http://heml.mta.ca/Amsat/ao16_cheap_vertical_indoors_30deg_to_10deg_23_01_2… I undertook the experiment because of half-broken outdoor equipment. My 435MHz antenna has an intermittent fault: it works properly when flipped over by the elevation rotor, but when under 90 deg. elevation, it is open. I don't dare drop the wooden mast I'm using until the weather improves (read, May), so I'm stuck. As the rotor flipped to track this bird, strangely I could still hear it. Either the antenna situation was improved, or the bird booms. SWR still awful: its the bird! That's basically just a piece of open coax with a preamp that's outside. So I quickly disconnected it, and connected the mini mag-mount that was at my station. I could hear QSOs even better. Amazing. If I have a chance, tomorrow I'm going to go outside with a FT-817 and see how we do with Crummy Antennas for Satellites :-) 73, Bruce VE9QRP

1 0

Re: AO-16 reconfigured
by Tom Clark, K3IO 23 Jan '08

23 Jan '08

Whoops -- In my first try, I accidentally hit the SEND key before I posted the message! Then, after composing this message, it got lost in the big stellar bit bucket & didn't get posted to AMSAT-BB. So I try a 3rd time -- --------------------------------------------- The news from Drew and the AO-16 command team came as a most pleasant surprise to me. As Drew, KO4MA said : > After the conclusion that the spacecraft computer system was damaged and as > discussions about decommissioning were taking place, Jim recalled a series > of low level commands included in the spacecraft design by Tom Clark, K3IO > during construction. One of these commands allows an uplink receiver to be > directly tied to a downlink transmitter. It is now Jan.22 and it is, to the day, the 18th anniversary of the Jan.22,1990 launch (for details, see http://128.54.16.15/amsat-new/satellites/satInfo.php?satID=11&retURL=/satel… <http://128.54.16.15/amsat-new/satellites/satInfo.php?satID=11&retURL=/satel…> and http://www.spacetoday.org/Satellites/Hamsats/Hamsats1990s/Hamsats90sMicrosa…) when the Ariane-4 carried the first 4 Microsats (AO-16, DO-17, LO-18 and WO-19) and 2 UoSATs (UO-14 and UO-15)into orbit. The success that Drew reported came about because of three engineering decisions we made 20 years ago while designing the Microsats (a fascinating narrative translated from Chinese can be found at http://tinyurl.com/2r82dv and also see KB5MU's report from the 1989 TAPR meeting at http://www.qrz.com/download/packet/tapr89.txt): 1. Hugh Pett, VE3FLL designed the MBL bootloader as a finite state machine, independent of the computer. In addition to providing a way to reload the computer, the MBL has the ability to load commands into the AARTs in each module. 2. I developed (with a LOT!! of help from Bob Stricklin, N5BRG) the new concept which I called the AART (Addressable Asynchronous Receiver/Transmitter) using the Motorola MC14469 chip. The AART board allowed two wire bus to send configuration commands to each module. . This was AMSAT's first spacecraft LAN (although it was only 6 inches long). Each AART board receives 2 byte packets (one for address, one for data) and returns a one byte response when it is addressed. The data byte is heavily multiplexed and sets up digital states and an analog telemetry multiplexer. The last time I heard, the AART on AO-16 had handled well over a billion packets. This is relevant because Hugh 's MBL allows a command station to send commands directly to each module even if the computer is brain dead. 3. In designing the Microsat receiver (with much engineering help from Eric Gustavson, N7CL & Jim Vogeler, WA7CJO, and construction help from Dick Daniels, W4PUJ and component scrounging by Lyle Johnson, KK7P), I implemented a bypass mode that allowed the AART to pass raw "audio" output from each receiver directly into the PSK xmtr. This was done mainly to facilitate testing after the module stack was assembled. I'll tell you that I am very proud that my boards are still working and the RX sensitivity is so good. Given 4 original Microsats with 5 individual receivers (except Dove with only 2 RX channels) and 4 AART boards running for 18 years (plus IO-26, AO-27 & MO-31) with plastic ICs and a lot of consumer grade components, AMSAT's "design them well and use industrial grade parts" philosophy seems to vindicated with a total of hundreds of years of on-orbit experience. Bob McGwier (N4HY) has collected a lot of Microsat photos on his website at http://n4hy.smugmug.com/AMSAT/245761. A few I spotted that might be interesting: * http://n4hy.smugmug.com/gallery/2052687#105508793 -- This page shows several pix of my RX and AART boards . There are 5 RX channels, 4 for the users and one for command. The pictures of bare copper PCB were mechanical mockups for vibration testing. In each shield area, the long chip is the Motorola MC3362 single channel FM RX chip. The large silver can just to the left of the 3362 (a dummy in mass model) in the middle of each RX channel is the 10.7 MHz 15 kHz wide xtal filter that Lyle Johnson found for us. The 2M front-end has a 3 section TOKO helical resonator following the MOSFET LNA. * At the bottom left of http://n4hy.smugmug.com/gallery/2052687#105508798 you see a resonant line that served as a 70 cm TX trap and part of the 2M input circuit. * http://n4hy.smugmug.com/gallery/2052709#105511134 -- shows eye patterns showing that the RX works @ 9600 Baud (i.e. 4800 Hz maximum audio frequency * http://n4hy.smugmug.com/gallery/2052709#105510099 -- the DOVE RX is on the left -- note that only 2 of 5 RX channels have been populated. * http://n4hy.smugmug.com/gallery/2052709#105511041 -- Bob still has SOME hair. * http://n4hy.smugmug.com/gallery/2052709#105511088 & http://n4hy.smugmug.com/gallery/2052709#105511116 -- Bob still gives me a hard time about having a mustache! Thanks to Drew, Gould, Doug, Jim, Mark & Bruce for this 18th Birthday present for AO-16. 73, Tom

2 1

AO-16 Success!
by John Marranca, Jr 23 Jan '08

23 Jan '08

The 2045z pass of AO-16 was fantastic! Without any difficulty, I was able to work VE3NPC, VE2DWE, W2XB (here in FN02), and AA4FL! (Boy...SSB Doppler is a bigger challenge!) Many many thanks to the Ground Team for doing such a great job resurrecting this satellite. Happy Birthday AO-16! John KB2HSH -- _______________________________ John Marranca, Jr PBX Technician/Shop Steward CWA Local 1122 BN Systems, Inc Orchard Park, NY (716)972-2006

1 0

Re: AO-16
by Clare Fowler 23 Jan '08

23 Jan '08

Great to have one of the microsats back again; Heard myself on 19:00 pass but no one else around but on 20:35 pass lots of activity and some of the usual QRMing with single channel FM uplink. Very easy to work and no trouble following doppler on SSB downlink. Worked AA4FL, VE2DWE, N4ZQ, KB2HSH, W2XB and K2MO. and just about everyone worked everyone. Clare VE3NPC

1 0

Command Team Congrats
by Bill Greene 23 Jan '08

23 Jan '08

Fantastic work Command Team! Now I have to get my antennas back configured to give it a try........well I think I will wait till the temperature gets a bit warmer , currently it is -16 C. Again great job to everyone involved. Regards, Bill Greene VE7WFG Armstrong BC DO00jk Amsat 29777

2 1

WTB: Paccomm PSK-1T
by Mark L. Hammond 23 Jan '08

23 Jan '08

Hello All, I am interested in buying a Paccomm PSK-1T (if the price is right). This is the unit with a built-in TNC. It would be useful for commanding AO-16.... If you have such a beast collecting dust, please reply directly to me at: n8mh(a)amsat.org Thanks! -- Mark L. Hammond [N8MH]

1 0

UO-11 up and running
by Mark M 23 Jan '08

23 Jan '08

Found UO-11 data beacon up and running on 145.825 on my 0249-0302 utc 20080123 pass. Please give a listen and let Clive, G3CWV at g3cwv(a)amsat.org know how well you have heard it, and that I was not imagining it. It was doing very well here without preamp on a 46 degree elevation pass. S7-9. With the preamp it flat lined 60 over plus.

3 3