January 2007 - AMSAT-BB - mailman.amsat.org

ARR Preamp Documentation
by Mark Brueggemann K5LXP 02 Jan '07

02 Jan '07

Poked around the web for a while and didn't see any downloadable data on ARR preamps. I am trying to find out what the exact DGFET/BPT/GaAsFET the 144 and 430 models use, and if the DGFETs/BPT/GaAsFET's are interchangeable. I anticipate blowing them up when I get my sat setup going soon, and I would like to order up some spare devices (exact replacements or suitable substitutes). I have the PxxxVDG's but I'm reading that the DGFET and bipolar versions are less ESD fragile than the GaAs ones albiet less gain. Is there an advantage to one over the other in practical ham satellite applications? Thanks, Mark K5LXP Albuquerque, NM

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First Design Meeting for P3D/AO-40 gallery
by Robert McGwier 02 Jan '07

02 Jan '07

The first design meeting for AO-40 has now been captioned. My sincerest thanks to James Miller for his invaluable memory/notes. http://n4hy.smugmug.com/gallery/2107966/ Bob N4HY -- AMSAT Director and VP Engineering. Member: ARRL, AMSAT-DL, TAPR, Packrats, NJQRP, QRP ARCI, QCWA, FRC. ARRL SDR WG Chair "If you board the wrong train, it is no use running along the corridor in the other direction. " - Dietrich Bonhoffer

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Re: MGF1402 source or substitute
by G0MRF＠aol.com 02 Jan '07

02 Jan '07

Hello Francesco Reading the articles, I see that the author of the original article in The Netherlands and OZ1PIF have both produced PCBs for the design. It may be worth an e-mail to them both to find out the current situation. - But I get the impression they are now out of stock If they have sold out, then you may be able to take the PCB for my 70 and 23CM version and adapt it for their 2m design. A quick look suggests that the biasing is similar although the input circuit is different. I did try a 2m version about a year ago, but the foil trimmers I used caused instability. A decent piston type trimmer as used by OZ1PIF would be a much better choice. The 0.8mm FR4 board design and details of the G0MRF 70cm amp can be found at: _http://www.g0mrf.freeserve.co.uk/432LNA.htm_ (http://www.g0mrf.freeserve.co.uk/432LNA.htm) 73 David In a message dated 1/2/2007 5:14:09 PM GMT Standard Time, iz5dwf(a)amsat.org writes: Hello David & group On Tue, 2 Jan 2007 G0MRF(a)aol.com wrote: > > 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_ > (http://www.frenning.dk/OZ1PIF_HOMEPAGE/144_and_432MHz-LNA.htm) very interesting! Do you know if someone is still selling the pcb for it? 73 es hny Francesco IS0FKQ

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XE2HWB from DL42/DL52 - 3 January 2007
by Patrick STODDARD (WD9EWK/VA7EWK) 02 Jan '07

02 Jan '07

Hi! I just received an e-mail from Bernardo XE2HWB, from La Paz in southern Baja California. He is traveling to Los Cabos today, and plans to be on 4 AO-51 passes from grids DL42 and DL52 tonight and tomorrow morning (all times below are Wednesday UTC): 0252 UTC 0431 UTC 1508 UTC 1647 UTC When calling XE2HWB, please be patient with his limited grasp of English. Don't speak too fast, and use standard phonetics. If you work him, his address on QRZ.com is good and mail service to southern Baja is not too bad. 73! Patrick WD9EWK/VA7EWK - Phoenix, Arizona USA http://www.wd9ewk.net/

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Re: MGF1402 source or substitute
by G0MRF＠aol.com 02 Jan '07

02 Jan '07

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_ (http://www.frenning.dk/OZ1PIF_HOMEPAGE/144_and_432MHz-LNA.htm) Good luck David G0MRF In a message dated 1/2/2007 11:24:37 AM GMT Standard Time, tyler881(a)adelphia.net writes: Thanks! rfparts.com has them listed, but doesn't have any. I tried them already. Thanks! i'll give the hamtv.com link a try! Tyler KM3G

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Eagle Decisions
by ANTHONY JAPHA 02 Jan '07

02 Jan '07

Just wanted to add my congratulations to the Board and the Eagle managers and design team for the decisions on what to put into the bird. They look like excellent choices that will provide much fun for many. 73, Tony, N2UN LM 183

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winorb
by Gerald Klatzko 02 Jan '07

02 Jan '07

Since upgrading to Windows XP Professional, I am having great difficulty in accessing Winorbit V3.6 1b, which previously worked for many years on the older Windows. After booting up the computer and calling up Winorbit, it sometimes comes up correctly, but most of the time it keeps coming up with an "Oveflow" window and on clicking "OK" it reverts to the Desktop. By rapid clicking 5 or 6 times on the winorbit Icon, I can eventually get one version to operate correctly after closing the "Overflow" ones. I have looked at the "Help" file and made sure that all suggestions are implemented. Has anyone solved this problem - help would be greatly appreciated. Gerald ZS6BTD

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MGF1402 source or substitute
by Peter Gayle 02 Jan '07

02 Jan '07

Terry, Your timing is perfect. I was also searching for the same device and came across a company in California that has them. I ended up ordering several of them because they are hard to come across. Take a look here. http://www.hamtv.com/specials.html Peter, VA3PK Hello all! I'm in the process of building up a LNA for 2 meters from an old copy of the ARRL handbook. The article calls for a MGF1402 GaAsFET. I have yet to be able to find any of those. Does anyone know of a source for MGF1402s? Does anyone have some they want to part with? I'm going to try to substitute in a NEC NE3509M04, but it's a bit of a challenge to solder to! What else have people substituted in for MGF1402 devices? Thanks, Tyler KM3G

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TS2000 or FT847 ?
by Dave Aitch 01 Jan '07

01 Jan '07

I introduced a friend to the world of amateur satellites today. He was very pleased/impressed to also have a QSO ( Thanks Ib) Mike is now trying to decide which transceiver to purchase, as per the title. I have owned/used both, but Mike would prefer some other opinions too. Mike wants and all in one box. No argument. What do you think ? Any major reasons to choose one over the other ? Mike is aware of the annoying UHF harmonics on the TS2000. Cheers, Dave. AMSAT UK 5766

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ANDE-MAA has deployed!
by Bob Bruninga 01 Jan '07

01 Jan '07

ANDE-MAA is alive and well. We have been communicating with her today, and signals are comparable to PCSAT-1. I even activated the voice synthesizer for a test today. Here is the good news from Cheyenne Mountain: > Just wanted to give you an update for our tracking of > ANDE. It appears as if we are currently tracking five > pieces from the ANDE deployment. SCC# 29663 is still > the ID on record and we have built four additional > analyst satellites with the remaining tracks. > > The pieces are separating quite nicely, but we're > waiting on a couple additional SSN sensors tracks before > we catalog the remaining pieces. I'll try to pass along > SCC ID numbers for the other four pieces as soon > as I have been informed. Bob Bruninga, Wb4APR US Naval Academy Satellite Lab

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