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Fw: Satellite Database Update
by Roger Kolakowski 06 Jan '07

06 Jan '07

For everyone's perusing pleasure: ----- Original Message ----- From: "SatelliteData Mailbox" <SatelliteData(a)ucsusa.org> To: "SatelliteData Mailbox" <SatelliteData(a)ucsusa.org> Sent: Friday, January 05, 2007 2:57 PM Subject: Satellite Database Update - Union of Concerned Scientists A new version of the UCS Satellite Database, which includes launches through December 27, 2006, has been posted at http://ucsusa.org/satellite_database . The new Excel format file is called "UCS_Satellite_Database_01-04-07.xls" and the tab-delimited text version is called "UCS_Satellite_Database_01-04-07.txt". The tab-delimited text version in which the "Name" column contains only the official name of the satellite in the case of government and military satellites, and the most commonly used name in the case of commercial and civil satellites is called "UCS_Satellite_Database_officialname_01-04-07.txt". The other changes to this version of the database include: * The addition of 27 satellites * The deletion of 11 inactive satellites * The addition of and corrections to some satellite data We have incorporated your corrections and suggestions as we were able, and continue to welcome your comments. The UCS Satellite Database Manager SatelliteData(a)ucsusa.org

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RAFT/ANDE Progress report
by Robert Bruninga 05 Jan '07

05 Jan '07

ANDE and RAFT are operatonal. There is a local TV clip now on the web page where the students discuss their satellite projects. See http://www.ew.usna.edu/~bruninga/ande-raft-ops.html Both signals are weak and require a beam and high elevations to hear them. As of this time, RAFT speech is enabled for special testing only in accordance with the User Service Agreement: http://www.ew.usna.edu/~bruninga/ande/ANDEcontract.txt During a 58 degrees max elevation pass, at about 45 degrees elevation, PA3GUO reports a successful voice packet via RAFT. The MP3 file is on the ANDE-RAFT-OPS web page above. A high elevation pass usually required. PLEASE NOTE! RAFT is underpowered for this voice mission, and so this capability should only be used by special demo stations and for special events or tests. The downlink is very weak and needs a beam and a high elevation pass to hear it. DO NOT TRANSMIT A VOICE PACKET IF YOU CANNOT HEAR THE DOWNLINK. You must adhere to the user service agreement above to use this capability. When ACTIVATED, RAFT will speak an APRS formatted MESSAGE addressed to the callsign of TALK. This APRS Message packet was Transmitted by PA3GUO: > PA3GUO-8>APRS,RAFT*::TALK :henk says hello First the packet is digipeated (lets you know it received it). Then (up to 10 seconds later), it should SPEAK the packet. In this case RAFT spoke: > "PA3GUO" + "says" + "henk says hello" Although the Speech synthesizer is ENABLED, it is normally OFF. To use it, someone in the footprint has to activate the voice module with a CONNECT REQUEST to "RAFT". On hearing a connect request, (the connecting station can do nothing else), RAFT responds in voice with "Welcome to TextSpeak". At that point, RAFT will speak any APRS formatted MESSAGES from anyone to TALK. Again, notice that if you see the successfully DIGIPEATED packet, then it will speak it, although there might be up to a 10 second delay. If you see such a successful APRS MESSGE to TALK digipeated, then everyone should hold off until it gets a chance to speak it. Notice the APRS MESSAGE format carefully. The callsign TALK is bracketed with colons and is padded to 9 characters with 5 spaces on the end. Oh, This speech was enabled with simply the connection of an off the shelf $200 text-to-speech module connected to the serial port (monitor) of the spaeccraft TNC. Kantronics made a slight software mode to replace the normal packet header with "CALLSIGN SAYS" before the packet is sent out the serial port. With this mod, you can use a radio, TNC and this voice module to create "voice at a distance"... But the high cost of the voice module will probably prohibit much terrestrial applications.. Bob Bruninga, WB4APR US Naval Academy Satellite Lab.

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Calculating Link Budgets
by john heath 05 Jan '07

05 Jan '07

Hi Bruce and the list, As usual, Satellite Handbook by Davidoff K2UBC has the answer. Chapter 8 page 12 has a fully worked out calculation on predicting signal levels. Its for a geostationary satellite with a 35W transponder and 70 users as follows: "The average power allocated to each user is therefore 0.5 watt." Hope this helps 73 john g7hia

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AO-51 reload begun
by Andrew Glasbrenner 05 Jan '07

05 Jan '07

The reload has been started. The downlinks will be silent for at least one day as this work proceeds. Thanks for the patience. 73, Drew KO4MA AMSAT-NA VP Operations

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Calculating link budgets with linear satellites
by Bruce Robertson 05 Jan '07

05 Jan '07

I've recently been toying with spreadsheets to estimate antenna requirements for some of the upcoming satellites. I'm not sure, however, how I should integrate the downlink power of a linear bird over its bandpass. Take for instance Delfi C3. It is said to have a 400mW downlink in a 40kHz bandpass. Does this mean that a solitary CW signal would be 400mW, two such signals (both with equal uplink power) would produce a 200mW downlink, etc.? In calculating power and pathloss using the simple addition and subtraction of dBm, what starting value is it recommended that I use in this case? 73, Bruce VE9QRP

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Re: AO-51 repeater off? (fwd)
by G0MRF＠aol.com 04 Jan '07

04 Jan '07

Hi Rich. No need to search the BB. Just have a look at the AO51 page on amsat.org _http://www.amsat.org/amsat-new/echo/ControlTeam.php_ (http://www.amsat.org/amsat-new/echo/ControlTeam.php) 73 David G0MRF In a message dated 1/3/2007 11:19:46 PM GMT Standard Time, n3wwn(a)futuretek.cx writes: I haven't seen this msg post to the list after about 5.5hrs, so trying again. 73 de Rich N3WWN (FN00fh) ---------- Forwarded message ---------- Date: Wed, 3 Jan 2007 12:42:05 -0500 (EST) From: n3wwn(a)futuretek.cx To: amsat-bb(a)amsat.org Subject: AO-51 repeater off? Hi! I'm sorry if I missed the posts which may answer my question. I don't see the answers in the amsat-bb archives.

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AO-7 back in full sun
by Andrew Glasbrenner 04 Jan '07

04 Jan '07

It looks like AO-7 is back in a period of continuous illumination, and the 24 hr timer is working. Perusing the data at http://www.planetemily.com/ao7/ao7log.php it looks like the daily mode change between Mode A and B is occurring around 1130 to 1145Z each day. Eclipses return April 3rd, 2007, and we expect the timer to be interrupted near this date. This is a good time to enjoy our old friend in a predictable manner, especially if you are a Mode A fan. Please keep your transponded signals from FMing as a too strong signal may reset the satellite, and make some contacts! 73, Drew KO4MA

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atf 54143 phemt (was MGF1402 source or substitute)
by K & R Yoksh 04 Jan '07

04 Jan '07

--- Original Message --- >Date: Tue, 2 Jan 2007 11:43:45 EST >From: G0MRF@xxxxxxxxx >Subject: [amsat-bb] Re: MGF1402 source or substitute >To: tyler881@xxxxxxxxxxxxxx >Hi Tyler. >The MGF1402 is an expensive option these days. >You may want to have a look at this 2m design which will give you 0.3 to >0.4dB noise figure. >(http://www.frenning.dk/OZ1PIF_HOMEPAGE/144_and_432MHz-LNA.htm) >Good luck >David G0MRF Hi everyone, I was reading about the ATF 54143 PHEMT device, and gathering parts for my own 432 LNA not long ago. The NF and gain specs look very attractive, but I could not find a single outlet in the USA to buy one! A phone call to the Customer Service number for Avego (formerly Agilent) got me a sample of 10 qty for absolutely FREE! I learned that Avego was not interested in selling less than 1000 pcs (the guy laughed when I tried to order 10). He told me that this item was stocked in Germany, and since I didn't want to buy the minimum qty, he'd go ahead and send me a free sample. I received my sample in about 2 days! They actually put it on an express DHL shipment.. It might have helped that I mentioned being a ham, and that my club and I were planning to build some LNAs.. If the name Agilent sounds familiar, it's because they also make BPL devices.. Maybe they wanted to appease a ham for a change? hi hi 73 and GL, Kyle Yoksh K0KN Olathe, Kansas Amsat # 35249

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AO-51 repeater off? (fwd)
by n3wwn＠futuretek.cx 04 Jan '07

04 Jan '07

I haven't seen this msg post to the list after about 5.5hrs, so trying again. 73 de Rich N3WWN (FN00fh) ---------- Forwarded message ---------- Date: Wed, 3 Jan 2007 12:42:05 -0500 (EST) From: n3wwn(a)futuretek.cx To: amsat-bb(a)amsat.org Subject: AO-51 repeater off? Hi! I'm sorry if I missed the posts which may answer my question. I don't see the answers in the amsat-bb archives. Is AO-51's repeater off at this point? Perhaps for the software reload? According to the ControlTeam page, I expected Echo to be in V/U repeater mode, but I haven't heard a peep out of her over the last few days (just got my satellite rig cabled up again... hopefully properly this time). I can work SO-50, so I know my setup is operational. Since the PL requirement was dropped, do I *NEED* to turn off the PL or will the bird just ignore it like a terrestrial repeater with a disabled PL? Thanks for the info! 73 de Rich N3WWN (FN00fh)

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Looking for National Semiconductor LM373
by Tom Matthews 04 Jan '07

04 Jan '07

Trying to tap the incredible resource here - Anyone know of a source for a quantity of 10 National Semiconductor LM373 IC's? Any suggestions appreciated & thanks for the bandwidth - Tom K5SAF

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