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Re: [amsat-bb] Shoppinglist (Making a T notch filter)
by GEO Badger 18 Mar '19

18 Mar '19

How about rolling your own? https://qrznow.com/145-mhz-low-loss-bandpass-helical-filter/ https://www.arrl.org/files/file/Technology/Intermod/No_Tune_Filter.pdf Or DCI? http://dci.ca/ ___ Sent from my two way wrist watch 73 de W3AB/GEOOn Mar 15, 2019, at 07:39, Hans BX2ABT <hans.bx2abt(a)msa.hinet.net> wrote: Hello all, Unfortunately it's not one transmitter, but four of them (I thought 5, but I just checked. Powers range from 1 - 10 kW), producing a lot of spurious signals and raising the noise floor by about 10 dB when pointing the beam into that direction. I don't think stubs will be broad enough to cover 89 to 106 MHz, but I never worked with them, so I'm guessing here. I don't have any problems with FM stations leaking onto 70 cm, just the air band, NOAA frequencies and 2 meters. My Airspy mini also picks up lots of spurious signals below 50 MHz, often hard enough to ID. I found this filter from Par Electronics (http://www.parelectronics.com/fm-broadcast.php), but it doesn't indicate if you can tx through it. Otherwise I will have to use it in the shack and remove it when I want to tx on 2m, with the risk of forgetting it and blowing it up. Will a sequencer be a solution then? 73 de Hans BX2ABT On 03/15/2019 09:42 PM, Robert Bruninga wrote: And you can make it without all the connectors at the T if you want. Though it takes some close and inventive soldering of the "T". Since the FM band is 88 to 108 that (I think) is far enough from 145 to add minimum loss. But at UHF, one needs to carefully check to make sure that the FM frequency is not also a multiple of the FM frequency. Tell us the FM broadcast frequency and we can take a quick look. Bob -----Original Message----- From: AMSAT-BB <amsat-bb-bounces(a)amsat.org> On Behalf Of Wendy and Terry Osborne Sent: Thursday, March 14, 2019 11:50 PM To: amsat-bb(a)amsat.org; Hans BX2ABT <hans.bx2abt(a)msa.hinet.net> Subject: Re: [amsat-bb] Shoppinglist Hi Hans, If you have a plenty of RG213 and suitable connectors, you could try making a Coax stub filter. You need a cable length that is an odd multiple of a quarter wave length long at the FM Tx frequency and an even multiple of a quarter wave at the frequency that you want (2M /70CMs). A single RG213 stub would have about 25dB of rejection and would pass 100 Watts OK. You just need a coax T connector and some matching connectors. To trim the stub, use a set of garden secateurs. If you have a Bao feng or similar radio you could use that on the FM band attached to your T and trim the stub for minimum signal on the unwanted Tx frequency.v dir="auto">I haven't run the calculations for how long the stub should be but if it's useful I could do so. 73, Terry Osborne ZL2BAC -----Original Message----- From: Hans BX2ABT Sent: Thursday, March 14, 2019 12:33 AM To: amsat-bb(a)amsat.org Subject: [amsat-bb] Shoppinglist My sis-in-law will be visiting from the States soon and I usually make her bring some stuff for me so I can save on freight costs. She will definitely bring an Arrow Antenna so I can start some portable operations. A Sony voice recorder is also on my list, as well as some coax cable (RG-400 is what I'm thinking of. Really expensive here). Don't have a budget for much more, but since I have a clear line-of-sight to some 10 kW FM transmitters from my QTH I thought I should at least get a good FM-band notch filter. Any recommendations on where to buy this in the US? I haven't found anything when I googled, not even a lot of 2/70 band pass filters, or low pass filters to prevent desensing on 70 cm. My own creations have a too high insertion loss, so this time I really want something a bit more professional and something that can handle at least 100 Watts of power. Any recommendations are welcome. Cheers. --Hans BX2ABT Sent via AMSAT-BB(a)amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb Sent via AMSAT-BB(a)amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb Sent via AMSAT-BB(a)amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb Sent via AMSAT-BB(a)amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb

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Re: [amsat-bb] Attaching the coax to antenna boom
by Frank Karnauskas 18 Mar '19

18 Mar '19

This is quite curious. Page 1 of the WA5VJB paper says, "Run the coax back down the antenna and along the boom keeping the radius small..." His hand-drawn illustration shows the feedline going down the boom then making a hard turn at the boom-to-cross arm plate. The M2 instruction sheets for the 2MCP8A and 436CP16 antennas both state (in bold type), "Do not route feedline to boom to mast plate as exiting antenna here will adversely affect circular field." Mr. Britain's paper is obviously focused on mounting the cross bar somewhere along the boom of a somewhat long antenna. The M2 instructions are for mounting short antennas from the back of the boom to the cross bar. Not the same situation. But, for a newbie like me, the definitive conclusion to this discussion is...I am still confused. I was hoping to hang my M2 LEO antennas Monday morning but now not until after I call the M2 support line for their read on this. 73, Frank FRANK W. KARNAUSKAS, N1UW ARRL MINNESOTA AFFILIATED CLUB COORDINATOR AMSAT NEWS SERVICE ROTATING EDITOR 1402 SUMMIT SHORES DR. BURNSVILLE, MN 55306 N1UW(a)GOKARNS.com 612-644-9174 -----Original Message----- From: AMSAT-BB [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Gary Sent: Sunday, March 17, 2019 2:29 PM To: radiomb; amsat-bb(a)amsat.org Subject: Re: [amsat-bb] Attaching the coax to antenna boom Yes, you can, just pay attention to how far your coax turn is from your driven element. There are a couple spots to avoid. It is pretty well explained in Kent Britain's (wa5vjb) paper here: http://www.kk0sd.net/metalboom/metalboom.htm 73, Gary kk0sd -----Original Message----- From: AMSAT-BB <amsat-bb-bounces(a)amsat.org> On Behalf Of radiomb Sent: Sunday, March 17, 2019 4:04 PM To: amsat-bb(a)amsat.org Subject: [amsat-bb] Attaching the coax to antenna boom Building my new ground station and another question. I have always only elevated my antenna 90 degrees. I loose about 20 25 seconds while the azimuth rotator turns 180 degrees to track the rest of the pass. I have just let the coax hang off the back of the antennas in a big loop. I am afraid it will get hung up going 180 degrees. Question, Can I attach the coax to the antenna boom and run it back until it gets to the cross boom or will that throw off the radiation pattern? Thanks 73 Mike K4MIA _______________________________________________ Sent via AMSAT-BB(a)amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb _______________________________________________ Sent via AMSAT-BB(a)amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb

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Looking for older AMSAT Journal article
by Bob Hammond 18 Mar '19

18 Mar '19

I need a copy of an article on Mark Spencer's minimalist preamp in the Nov/Dec 2012 Journal. Anyone have a copy? 73, Bob W7OTJ

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Upcoming ARISS contact with North Point School for Boys, Calgary, Alberta, Canada - CORRECTED RELEASE
by n4csitwo＠bellsouth.net 18 Mar '19

18 Mar '19

CORRECTED RELEASE: Please note that the original ARISS press release for North Point School for Boys, Calgary, Alberta, Canada sent on 3/17/2019 at 11:43 UTC, stated that the contact should be audible over Alberta, Canada. This was incorrect. The contact will instead be audible over Italy and adjacent areas. We sorry for any inconvenience this may have caused. Below is a corrected copy. ---------------------------------------- An International Space Station school contact has been planned with participants at North Point School for Boys, Calgary, Alberta, Canada on 20 Mar. The event is scheduled to begin at approximately 20:16 UTC. It is recommended that you start listening approximately 10 minutes before this time.The duration of the contact is approximately 9 minutes and 30 seconds. The contact will be a telebridge between OR4ISS and IK1SLD. The contact should be audible over Italy and adjacent areas. Interested parties are invited to listen in on the 145.80 MHz downlink. The contact is expected to be conducted in English. North Point School for Boys, a private school in Calgary, provides a setting for boys from Kindergarten to Grade 9 in which they are challenged and motivated, developing into young men of integrity with a genuine love of learning. Through strong mentors, experiential learning and blended learning, students discover who they are and how they learn. Students will be learning about the International Space Station through social discussion, science class and engineering academy. Students will be building a scale model of the International Space Station and learning Canada's commitment to the space program. Participants will ask as many of the following questions as time allows: 1. How did you train to become an astronaut? 2. What do you do all day? 3. Is time different on the space station? 4. What is it like being weightless in space? 5. Is it hard to move around? 6. What is your favourite space food? 7. What is the coolest thing you have seen while on the space station? 8. How long does it take to get used to zero gravity? 9. What did you bring with you to the International Space Station? 10. Was it scary launching on the Space Shuttle? 11. Will you get to do a spacewalk? 12. Do you operate the Canadarm? 13. What does the sunrise look like? 14. How long was the Soyuz ride? 15. What is your rank with the Canadian Space Agency? 16. Do you get to see all the parts of the International Space Station? 17. Can you see Canada from space? 18. How do astronauts breathe with their EVA suits on? 19. Do astronauts eat together? 20. What is it like being in space? PLEASE CHECK THE FOLLOWING FOR MORE INFORMATION ON ARISS UPDATES: Visit ARISS on Facebook. We can be found at Amateur Radio on the International Space Station (ARISS). To receive our Twitter updates, follow @ARISS_status Next planned event(s): TBD About ARISS: Amateur Radio on the International Space Station (ARISS) is a cooperative venture of international amateur radio societies and the space agencies that support the International Space Station (ISS). In the United States, sponsors are the Radio Amateur Satellite Corporation (AMSAT), the American Radio Relay League (ARRL), the Center for the Advancement of Science in Space (CASIS) and National Aeronautics and Space Administration (NASA). The primary goal of ARISS is to promote exploration of science, technology, engineering, and mathematics (STEM) topics by organizing scheduled contacts via amateur radio between crew members aboard the ISS and students in classrooms or informal education venues. With the help of experienced amateur radio volunteers, ISS crews speak directly with large audiences in a variety of public forums. Before and during these radio contacts, students, teachers, parents, and communities learn about space, space technologies, and amateur radio. For more information, see www.ariss.org, www.amsat.org, and www.arrl.org. Thank you & 73, David - AA4KN --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

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VK5DG/p in PF92, PF93
by David Giles 18 Mar '19

18 Mar '19

Hello All, I will be participating in the 6th VK5 National and Conservation Parks Activation Weekend on Saturday the 23rd of March. In the morning I will be in Little Dip Conservation Park (PF92) and the afternoon will be in Butcher Gap Conservation Park (PF93). I will be trying as many passes as I can on FM and SSB birds. 73 de David VK5DG

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Upcoming ARISS contact with North Point School for Boys, Calgary, Alberta, Canada
by n4csitwo＠bellsouth.net 17 Mar '19

17 Mar '19

An International Space Station school contact has been planned with participants at North Point School for Boys, Calgary, Alberta, Canada on 20 Mar. The event is scheduled to begin at approximately 20:16 UTC. It is recommended that you start listening approximately 10 minutes before this time.The duration of the contact is approximately 9 minutes and 30 seconds. The contact will be a telebridge between OR4ISS and IK1SLD. The contact should be audible over Alberta, Canada and adjacent areas. Interested parties are invited to listen in on the 145.80 MHz downlink. The contact is expected to be conducted in English. North Point School for Boys, a private school in Calgary, provides a setting for boys from Kindergarten to Grade 9 in which they are challenged and motivated, developing into young men of integrity with a genuine love of learning. Through strong mentors, experiential learning and blended learning, students discover who they are and how they learn. Students will be learning about the International Space Station through social discussion, science class and engineering academy. Students will be building a scale model of the International Space Station and learning Canada's commitment to the space program. Participants will ask as many of the following questions as time allows: 1. How did you train to become an astronaut? 2. What do you do all day? 3. Is time different on the space station? 4. What is it like being weightless in space? 5. Is it hard to move around? 6. What is your favourite space food? 7. What is the coolest thing you have seen while on the space station? 8. How long does it take to get used to zero gravity? 9. What did you bring with you to the International Space Station? 10. Was it scary launching on the Space Shuttle? 11. Will you get to do a spacewalk? 12. Do you operate the Canadarm? 13. What does the sunrise look like? 14. How long was the Soyuz ride? 15. What is your rank with the Canadian Space Agency? 16. Do you get to see all the parts of the International Space Station? 17. Can you see Canada from space? 18. How do astronauts breathe with their EVA suits on? 19. Do astronauts eat together? 20. What is it like being in space? PLEASE CHECK THE FOLLOWING FOR MORE INFORMATION ON ARISS UPDATES: Visit ARISS on Facebook. We can be found at Amateur Radio on the International Space Station (ARISS). To receive our Twitter updates, follow @ARISS_status Next planned event(s): TBD About ARISS: Amateur Radio on the International Space Station (ARISS) is a cooperative venture of international amateur radio societies and the space agencies that support the International Space Station (ISS). In the United States, sponsors are the Radio Amateur Satellite Corporation (AMSAT), the American Radio Relay League (ARRL), the Center for the Advancement of Science in Space (CASIS) and National Aeronautics and Space Administration (NASA). The primary goal of ARISS is to promote exploration of science, technology, engineering, and mathematics (STEM) topics by organizing scheduled contacts via amateur radio between crew members aboard the ISS and students in classrooms or informal education venues. With the help of experienced amateur radio volunteers, ISS crews speak directly with large audiences in a variety of public forums. Before and during these radio contacts, students, teachers, parents, and communities learn about space, space technologies, and amateur radio. For more information, see www.ariss.org, www.amsat.org, and www.arrl.org. Thank you & 73, David - AA4KN --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

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Attaching the coax to antenna boom
by radiomb 17 Mar '19

17 Mar '19

Building my new ground station and another question. I have always only elevated my antenna 90 degrees. I loose about 20 25 seconds while the azimuth rotator turns 180 degrees to track the rest of the pass. I have just let the coax hang off the back of the antennas in a big loop. I am afraid it will get hung up going 180 degrees. Question, Can I attach the coax to the antenna boom and run it back until it gets to the cross boom or will that throw off the radiation pattern? Thanks 73 Mike K4MIA

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AMSAT on HF
by skristof＠etczone.com 17 Mar '19

17 Mar '19

For anyone interested in the AMSAT on HF award I will be calling "CQ AMSAT" in slow code 1800 UTC to 1830 UTC today (Sunday). Frequency will be between 7.105 MHz and 7.115 MHz. Award info: https://www.amsat.org/amsat-50th-anniversary-awards-program/ Steve AI9IN

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Rovin' the Eights (and Sevens)
by Alex Free - N7AGF 17 Mar '19

17 Mar '19

AMSAT Grid Chasers, My semiannual rover trip to activate rare and somewhat rare grids will happen from April 29th to May 4th or 5th (or longer depending on how things go). I will fly into Minneapolis and drive back to my home grid CN88, activating as many ENx8,ENx7,DNx8,and DNx7 grids as possible along the route. Hopefully I can hit many corners and lines. I will be on both linear and FM birds. As always, activations and route details will be posted to my Twitter @N7AGF at https://twitter.com/N7AGF. I will also be on APRS at https://aprs.fi/N7AGF-10. In areas of limited cell service, I'll be using inReach. Email or hit me on twitter with grid requests, route suggestions, or hot tourist attractions in Minot. 73, Alex Free N7AGF

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AO-92
by Frank Staffa Jr. 17 Mar '19

17 Mar '19

I apologize to everyone trying to come back to my call just now but we had a CLOWN on there constantly throwing a dead carrier and also whistling on top of everyone. Don't know if anyone else heard him/her but it was annoying and one reason why FM sats can be discouraging. Again I apologize to everyone trying to come back to my call. Sent from Yahoo Mail on Android

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