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

Looking for 10 Mtr loop info
by Ronald Nutter 05 Apr '08

05 Apr '08

I am trying to put together an antenna for AO-7 downlink on 10 meters. At one point I had a copy of an article from an older AMSAT journal but due to a move last year across country, I seem to have misplaced it. Does anyone happen to have a copy they can share with me ? I am trying to get fluent with the SSB birds prior to Field Day since the FM birds will pretty be useless that weekend. Thanks, Ron KA4KYI

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2M1EUB/P qrv io87rj on sats
by paul robinson 05 Apr '08

05 Apr '08

Hi group ill be qrv once again from io87rj near aberdeen scotland from 12.04.08 for 7 days. its not an easy location for stateside but possible,if you wish to work me ,please be quick as only a small window for USA! would also be good to work some new calls from the states!! Europe window is ok! Ill be on all birds but mainly ao7 ssb .i will also be 160 and 80m as well as some hf ssb! check out the qrz web page under 2m1eub ,theres a nice photo and info.qsl is via home call 2e1eub.73 de paul amsat uk/na member --------------------------------- Yahoo! for Good helps you make a difference

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Delfi3C
by G0MRF＠aol.com 05 Apr '08

05 Apr '08

From: _http://www.delfic3.nl/photoblog/_ (http://www.delfic3.nl/photoblog/) Provisional launch date April 21st April 4th, 2008 Greetings from the clean room at Sriharikota! The Delfi-C3 checkout team has safely arrived at the launch site in India, and we are currently performing all checks on the spacecraft. So far, everything goes as planned and we have found no problems. It is great to meet the other teams and see all the other spacecraft which accompany Delfi-C3 on the launch, everyone is excited and can’t wait to see their satellite fly. Unfortunately, photography is not allowed on the base so you’ll have to use your imagination for now:) Meanwhile, we will try to keep you updated by posting text-only blog entries. At this very moment, the team is building up the satellite into launch configuration, which means attaching the solar panels, the wireless sun sensors, and applying the final pieces of thermal tape and locking glue. All major health checks have been successfully completed up to this point so we know the spacecraft is in good health. Furthermore, the linear transponder was tested for the last time before launch, and it worked just fine. Tomorrow is the last day we can work before we have two days off due to Indian national holidays. Frequencies: * Primary telemetry downlink: 145.870 MHz 1200 Baud BPSK AX.25 400mW * Backup telemetry downlink: 145.930 MHz 1200 Baud BPSK AX.25 400mW * Linear transponder passband downlink: 145.880 - 145.920 MHz (inverting) 400mW PEP * Linear transponder passband uplink: 435.570 - 435.530 MHz * Transponder mode beacon: 145.870 MHz CW (10dB below transponder PEP)

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Re: Delfi3C
by Wouter Jan Ubbels 05 Apr '08

05 Apr '08

Hi David & the rest of the BB, yes we have safely arrived in India, I am currently sitting next to the spacecraft as I type this e-mail:) So far, everything is going well with the checkout. We also did a successful transponder test yesterday. You might also want to check our weblog at http://www.delfic3.nl/photoblog where we will post updates, photos are not possible since photography is not allowed here. 73, Wouter Jan Ubbels VU/PE4WJ

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Re: Delfi3C
by Wouter＠delfic3.nl 05 Apr '08

05 Apr '08

Hi David & the rest of the BB, yes we have safely arrived in India, I am currently sitting next to the spacecraft as I type this e-mail:) So far, everything is going well with the checkout. We also did a successful transponder test yesterday. You might also want to check our weblog at http://www.delfic3.nl/photoblog where we will post updates, photos are not possible since photography is not allowed here. 73 de VU/PE4WJ

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EggBeater II antennas
by Jeff Moore 05 Apr '08

05 Apr '08

Hi there, I've just recently started working some of the sats (AO-51, SO-50, and AO-27 so far). I'm using a 2m mobile with a vertical ground-plane for uplink and a 6 element yagi with HT for downlink. I've been wondering how effective the Eggbeater II antenna design would be for the downlink (70cm). Anyone using this antenna design to work the satellites? Any advice appreciated. Thanks and 73, Jeff Moore -- KE7ACY CN94ib Bend, Oregon

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Preamp for a Mobile Application
by Kent R. Frazier 05 Apr '08

05 Apr '08

Hi all, I am really enjoying the satellite aspect of the hobby and have enjoyed the contacts I have made with my Icom IC-2720H with a 19" whip antenna from my vehicle. I have seen talk recently of using a preamp to improve the reception. From what I've read and understand, it appears that a "switching" preamp is needed for a setup using only one antenna for Tx and Rx such as mine. Is this correct? It also appears that most of the preamps are mast mounted. Since this would not be an option for me can the preamp be put near the transceiver? Are there any issues that result of doing so? Lastly, what preamp(s) would you recommend for an application such as mine? Thanks, Kent -- Kent R. Frazier, K5KNT

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Re: Best HT's for sats?
by Bill Dzurilla 05 Apr '08

05 Apr '08

Dan, Thanks for uploading the paper, very helpful. Guess no one rig can please everyone, but what is it about the FT-530 that makes it "very awkward to operate"? Drew KO4MA gave the FT-530 high praise in his post. I could never hear my downlink on the IC-W32A I borrowed for Swan Island, and if you can't use it to work full duplex, might as well buy a brand new FT-60 for about the same price as the W32A sells for on eBay. Also, you can't work the ISS with an unmodified W32A, as it won't transmit below 440 mhz. I know it's possible to hear your downlink on the FM birds with some rigs, because many have written about it. I've had no luck with 3 different rigs, even with separate radios and separate antennas. No problem for me to work duplex on AO-7 and VO-52, must be the third harmonic that is the issue with AO-51, AO-27, and SO-50. A lot of folks seem to like the Kenwood TH-D7A, but the price tag is quite high for a radio that is "very delicate," "extremely difficult to program," and "poor battery life". 73, Bill NZ5N >>Posted by: "Dan O'Barr" kl7dr(a)yahoo.com kl7dr Thu Apr 3, 2008 9:13 pm (PDT) I uplaoded my white paper on the best Walkie-Talkies to operate the LEO Amateur satellites. >>You can access this file at the URL: http://groups. yahoo.com/ group/fm-satellite/files/Best%20Walkie-Talkies.doc 73, Dan O, KL7DR ____________________________________________________________________________________ You rock. That's why Blockbuster's offering you one month of Blockbuster Total Access, No Cost. http://tc.deals.yahoo.com/tc/blockbuster/text5.com

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cross boom?
by w0dxz＠aol.com 05 Apr '08

05 Apr '08

In putting together my antenna,?? (144-432)I need something to use as a horizontal- cross? support boom. What would be the best length, and,? what would be the minimum length,,,? would 6? ft separation be OK?? To minimize problems, should I mount one beam horizontal, one vertical? Does it matter which one, is? which way? I doubt I can find a fiberglas boom locally,,,? what else could I use?? or, where can I order a fiberglas boom? thanks Bob W0DXZ

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Re: Best HT's for sats?
by Andrew Glasbrenner 05 Apr '08

05 Apr '08

Bill, The 530 lets you select one band as the transmit band, and the other as the band that the dial tunes. Simply set the 2m side to the 2m uplink, the 70cm to the downlink + expected doppler shift, set the sub band tune to tune the 70cm side, and then when you push the ptt it will transmit on 2m. The only thing you'll need to touch during the pass is the main tuning knob, and the PTT. This feature is only on the 530, on the 470 you have to swap bands, tune, then swap back before transmitting. With the 470 figure on doing this 5 times on a long pass, and I was always able to do it with one hand, even with gloves standing knee deep in snow in South Dakota. To answer an earlier question (or to not answer it) I've never had the need or desire to operate a full duplex rig where the receive band mutes on tx. There are cheap earphones that work for full duplex just about everywhere. I still use a pair I picked up for free from JetBlue two years ago. If I'm doing a demo where I want others to hear, like at a hamfest, I have an extension speaker from MFJ (read CHEAP) that I screwed a belt clip from an old cell phone onto, so that it clips to the back of my belt facing the other way from me. This and careful volume control will normally prevent it from squealing due to feedback. Think about this...full duplex means you can tweak your antenna orientation WHILE transmitting for max signal. All the FM microsats use a single whip for receive, meaning a linear yagi like the Arrow will have ~20db!!! of variation on the uplink due to cross polarization. If on your next dxpedition, would you bring along a 500w amp if it only had the size and weight of a pair of earbud headphones? 73, Drew KO4MA ----- Original Message ----- From: "Bill Dzurilla" <billdz.geo(a)yahoo.com> To: <amsat-bb(a)amsat.org> Sent: Friday, April 04, 2008 8:20 PM Subject: [amsat-bb] Re: Best HT's for sats? You mean you have to switch to the receive VFO and then switch back to the uplink VFO every time we need to make a Doppler correction? It's not cold here in Florida, but I can sure see how that would be annoying. Andrew said the FT-530 has a "subband tune function," what about that? 73, Bill > --- Dan O'Barr <kl7dr(a)yahoo.com> wrote: > > > Hi Rafael and Bill, > > > > That's the issue with the FT-530, and it's the > same > > with the Alinco DJ-580. > > They are both very good radios for full duplex. If > > you are in a warm climate, > > and do not have to wear gloves, then all the > button > > pushing to change back and > > forth between VHF for transmitting and then to UHF > > for receiving and changing > > frequencies for Doppler, then it's no big deal. > > However, up here the ability to > > just program 5 spit channels, like the VX-7R, > makes > > it a lot easier to work a > > pass. I believe the FT-51 has the capability of > > working full duplex with a > > setting that allows the operator to transmit on > one > > band and receive and tune > > on the other. ____________________________________________________________________________________ You rock. That's why Blockbuster's offering you one month of Blockbuster Total Access, No Cost. http://tc.deals.yahoo.com/tc/blockbuster/text5.com _______________________________________________ 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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