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

QSO via AO7
by F2lq＠aol.com 25 Jan '08

25 Jan '08

Good afternoon To night i have qso a K station asking my call , but it was just at the end of the pass ! Sorry...a next time perhaps ! If you read this little return... 73's Guy F2LQ IN98eb

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Re: AO-16 report
by Mark L. Hammond 25 Jan '08

25 Jan '08

Actually, this is a great idea, Greg. It's the basis for AE4JY Moe Wheatley's AO40RCv program--the 400BPSK demodulator. In fact, his source coded is posted--it should help with the programming I'd think. It provided button pushes, com port selection, radio choices, etc. Not sure there is ENOUGH carrier..at least from what I've been hearing. But I haven't looked at it with a waterfall yet; Drew KO4MA was doing that during our initial tests--he could see the carrier well as I recall. 73, Mark N8MH _______ Date: Thu, 24 Jan 2008 22:55:47 -0800 From: "Greg D." <ko6th_greg(a)hotmail.com> Subject: [amsat-bb] Re: AO-16 report To: <amsat-bb(a)amsat.org> Message-ID: <BLU133-W280FF8A5783F16558CB4AAA9390(a)phx.gbl> Content-Type: text/plain; charset="iso-8859-1" If there is a slight carrier on the downlink side, I wonder if someone with a sound card and a "bit" of spare time could work up an automatic tuning adapter? Zero beat the carrier by tickling the mike up and down buttons; something like that. You'd need to sample (tap into) the received audio, and manually get the receiver close. Then let it run. Crazy idea? Greg KO6TH

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Re: AO-16 report
by John W Lee 25 Jan '08

25 Jan '08

Also if you have an SSB receiver with DSP or automatic notch filter, you can eliminate the carrier completely. 73, John K6YK On Thu, 24 Jan 2008 13:43:26 -0500 "Andrew Glasbrenner" <glasbrenner(a)mindspring.com> writes: > Hi Ray, > > Thanks for the report, and I hope you don't mind that I have > included part of it in this email to -bb in response to a few > comments I've seen. As Ray and others have noticed, there is indeed > some carrier on the downlink. It isn't what we might have designed > for a voice system, but given how this came about, it's tolerable. > >> > 73, Drew KO4MA > > > ----- Original Message ----- > From: RaySoifer(a)cs.com > > The uplink is very sensitive indeed, and the downlink is as > expected given the power level. I would add, though, that in > addition to the DSB audio, there is a carrier output which helps to > tune in the downlink signal. It's not really DSBSC (suppressed > carrier) but more like DSBRC (reduced carrier, relative to what it > would be on AM). > > _______________________________________________ > Sent via AMSAT-BB(a)amsat.org. Opinions expressed are those of the > author. > Not an AMSAT-NA member? Join now to support the amateur satellite > program! > Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb > >

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Re: the state of AO16 batteries
by Mark L. Hammond 25 Jan '08

25 Jan '08

Hi Robert, Great question!! We can get VERY little telemetry out of AO-16 given its current health condition. We get a bit of MBL telemetry, and it looks fine--but it doesn't say a whole lot. During the multiple attempts of loading the housekeeping code to AO-16, the bird ran JUST long enough to spit out ONE "regular" telemetry frame--and I recorded the pass, so I caught the packet :) The voltages on the batteries look good, based on one telemetry frame. We don't know how the batteries will hold up during various eclipse periods. But you can be sure we'll do our best to manage what we have the ability to manage with the bird. We are able to set the power output of AO-16, so that is an obvious way to help manage its power budget. Also, we can shut the transmitter OFF, should it be necessary. User observations and feedback will be very helpful when we resume esclipes in the new "best pipe mode"! 73, Mark N8MH -----Forwarded Message----- >From: Robert Turlington <rob_g8ate(a)hotmail.com> >Sent: Jan 25, 2008 11:02 AM >To: Amsat Buleitin Board <amsat-bb(a)amsat.org> >Subject: [amsat-bb] the state of AO16 batteries > > >Hi All >does anyone know the condition of AO16 batteries (bearing in mind its age) at the moment the Sat is in full sunlight all of the time but after the 27th March it starts its eclipse season,so it will be interesting to see how things go on! >PS. I will be looking for contacts with NA on late afternoon/early evening mid atlantic passes over the next few days.Regards Robert G8ATE >_________________________________________________________________ >Who's friends with who and co-starred in what? >http://www.searchgamesbox.com/celebrityseparation.shtml >_______________________________________________ >Sent via AMSAT-BB(a)amsat.org. Opinions expressed are those of the author. >Not an AMSAT-NA member? Join now to support the amateur satellite program! >Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb -- Mark L. Hammond [N8MH]

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AO-16 report number 2 from Copenhagen
by OZ1MY 25 Jan '08

25 Jan '08

Hi all, A few observations from today: The transmit frequency seems to change a little. On the first pass I used today I had to go up 500 Hz on the downlink to hit the right frequency. On the later passes the change was smaller. As others have observed the carrier is there. Tuning to zero beat puts you spot on frequency. Following Toms e-mail I tried to change to FMN (3.5 kHz deviation) on the transmitter. That makes the audio sound better - but my downlink signal to noise ratio decreased. That was to be expected. I do not know about other areas of the World - but here over Europe the background noise on the downlink is very high. Did not experience the normal FM quieting effect by increasing the uplink power. I do not understand that - any ideas ? Is AO-16 making the noise itself ?? The polarity of the downlink antenna is difficult to make out. I thought it is RHCP - but Mark says LHCP. For me on the passes to the East RHCP is best ! Passes from the South - LHCP is best ! That is a general observation - some times it helped to switch during the passes. AO-16 might be tumbling a lot ? Another thing is that using Noise Reduction on my IC-910 helps a little - not much. Have fun and thanks to the team and the builders. 73 OZ1MY Ib

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the state of AO16 batteries
by Robert Turlington 25 Jan '08

25 Jan '08

Hi All does anyone know the condition of AO16 batteries (bearing in mind its age) at the moment the Sat is in full sunlight all of the time but after the 27th March it starts its eclipse season,so it will be interesting to see how things go on! PS. I will be looking for contacts with NA on late afternoon/early evening mid atlantic passes over the next few days.Regards Robert G8ATE _________________________________________________________________ Who's friends with who and co-starred in what? http://www.searchgamesbox.com/celebrityseparation.shtml

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Spoutnik 41-AMSAT-F
by Bob Cutter 25 Jan '08

25 Jan '08

Is it possible to get a QSL for a contact with Spoutnik 41? I have seen the log on AMSAT-F. 73, Bob KI0G ____________________________________________________________________________________ Looking for last minute shopping deals? Find them fast with Yahoo! Search. http://tools.search.yahoo.com/newsearch/category.php?category=shopping

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AO-16 reception on mode-AM
by JA0CQP 25 Jan '08

25 Jan '08

Hi All, On the 06:06(UTC) pass over Japan, I have tried to receive downlink signal from AO-16 on mode-AM. As a result, I have enjoied better sound quality and easy tuning than USB in spite of heavy QRMs. (However, against deep QSB, USB mode offers some advantage for better readability. .) TRX which I used is Kenwood TS-2000 with SatPC32 At the TS-2000, minimum tuning step on the VHF, and UHF bands mode-AM are 5KHz, hence "fine tuning" by SatPC32 was absolutory necessary. Thanks to SatPC32. 73s Toyo Komatsu- JA0CQP

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Re: RFI identification
by Wayne Estes 25 Jan '08

25 Jan '08

Joe (no callsign given) wrote: Computers are also extremely noisy! When operating HF I never use a computer, every one I have ever had or used, adds at least 10 DB to the noise floor. Wayne replies: How close are your HF antennas to you computers? I don't notice an increase in the HF noise level from the computers in my house, but my HF vertical and HF dipole feedpoint are both 60 feet from the house (and even further from neighbor's houses). At the closest point the dipole's wire is less than 30 feet from two computers in the house. Do you use CRT monitors with your computers? I found that CRT monitors generate much more RF noise than the average home computer. LCD monitors produce far less RFI. Weak-signal ham operators should NEVER use CRT monitors. Wayne Estes W9AE Oakland, Oregon, USA, CN83ik

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AO-16 report
by Piero Baudino 25 Jan '08

25 Jan '08

Hi to the group! Just worked AO-16 this morning: - worked RW3XL and EB3SA between 5.24 and 5.35 UTC - very strong signal, sometimes better in LHCP, using my 2x15 elements antenna and PREAMP (always S7-S9 on IC-910) - voice quality better on USB - very diffult to tune the downlink, between 437.034 (AOS) and 437.014 (LOS) for me... - uplink very sensitive, worked all the pass with only 1-2 W and my 2x7 elements antenna (always on RHCP) Many thanks to the AO-16 command team, great job guys! '73 de Piero IZ1ERR (JN35UI)

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