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

Re Power Levels Into Satellites
by Mike Hooles 25 Apr '07

25 Apr '07

What would be useful for people coming into the satellite world would be a series of maximum recommended power levels for each of the satellites listed on the AMSAT Website, e.g. SO50, Antenna - Eggbeater - 50 watts up to 30 degrees, 10 watts above. 1/4 wave ground plane - 50 watts 3 ele. beam 10 ele beam 12 ele beam etc. Also, listing modes. At the moment, many make the excuse they do not have the time, information, nor skills to calculate the levles. They're usually the ones that are 'deaf as a post' on the downlink as well Then any alligators could be steered to the relevant list. Best Regards Mike G3LGR 33643

2 1

Re: Re Power Levels Into Satellites
by Ricardo Trujillo 25 Apr '07

25 Apr '07

Used to be that the rule of thumb was to keep your signal below the level of the beacon...I don't know if that applies to the current birds. 73, Ricardo, W3/HK4BHA -----Original Message----- From: amsat-bb-bounces(a)amsat.org [mailto:[email protected]] On Behalf Of Mike Hooles Sent: Wednesday, April 25, 2007 9:43 AM To: AMSAT Subject: [amsat-bb] Re Power Levels Into Satellites What would be useful for people coming into the satellite world would be a series of maximum recommended power levels for each of the satellites listed on the AMSAT Website, e.g. SO50, Antenna - Eggbeater - 50 watts up to 30 degrees, 10 watts above. 1/4 wave ground plane - 50 watts 3 ele. beam 10 ele beam 12 ele beam etc. Also, listing modes. At the moment, many make the excuse they do not have the time, information, nor skills to calculate the levles. They're usually the ones that are 'deaf as a post' on the downlink as well Then any alligators could be steered to the relevant list. Best Regards Mike G3LGR 33643 _______________________________________________ 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

1 0

Re: CAPE-1 CW heard again (Correction)
by Mineo Wakita 25 Apr '07

25 Apr '07

CAPE-1 #31129, 435.245 MHz CW every 60 seconds intervals Apr 25, 12:44-12:58 UTC, 2007 Apr 25, 21:44-21:58 JST, 2007 Max ele, 81.4 deg Very rough sound like brooming, http://www.ne.jp/asahi/hamradio/je9pel/70425ca1.wav http://www.ne.jp/asahi/hamradio/je9pel/70425ca2.wav (Correction) --------------------------------------------- Name: Mineo Wakita / JE9PEL, JAMSAT member Mail: ei7m-wkt(a)asahi-net.or.jp URL : http://www.ne.jp/asahi/hamradio/je9pel/ QTH : Yokohama Japan, GL:pm95tj Date: Apr 25, 2007 ---------------------------------------------

1 0

Re: Government control has exceeded constitutionallimitations.
by Floyd Rodgers 25 Apr '07

25 Apr '07

Does anyone have any idea as to why only these two sites are still operating? Is that the only directions we have expectations of inbounds or is there some other reason? I would have thought by now we would have several other ways to detect objects.

5 4

CFR 47 Part 97.213 (was Government Control....)
by Joe Leikhim 25 Apr '07

25 Apr '07

For those who forgot or just don't know..... I was surprised to look at the map and see how much of Florida is included in the resriction. Repeater owners, are you sure your transmitter is only set to 50 watts? I was surprised the Florida Repeater Council webpage didn't seem to mention this. Perhaps I missed it. (f) No station may transmit with a transmitter power exceeding 50 W PEP on the UHF 70 cm band from an area specified in footnote US7 to §2.106 of the FCC Rules, unless expressly authorized by the FCC after mutual agreement, on a case-by-case basis, between the District Director of the applicable field facility and the military area frequency coordinator at the applicable military base. An Earth station or telecommand station, however, may transmit on the 435-438 MHz segment with a maximum of 611 W effective radiated power (1 kW equivalent isotropically radiated power) without the authorization otherwise required. The transmitting antenna elevation angle between the lower half-power (-3 dB relative to the peak or antenna bore sight) point and the horizon must always be greater than 10°. -- Joe Leikhim K4SAT "The RFI-EMI-GUY"© "Treason doth never prosper: what's the reason? For if it prosper, none dare call it treason." "Follow The Money" ;-P

3 2

AO-7
by John Hackett 25 Apr '07

25 Apr '07

Hi All, Somebody knocking 10 kinds of the brown stuff out of AO-7 this morning on orbit 48458. Careful !! with the power chaps or we'll lose this one as well. The recommended operating proceedure can be found at ... <http://www.planetemily.com/ao7/ao7log.php> Just click on "Using AO-7". The more potential new users who are aware that you *DON'T* need 100w to a 10 element beam, the more likely it is that AO-7 will continue to provide excellent analogue signals. 73 John. <la2qaa(a)amsat.org>

1 0

Re: FW: ARLB013 ARRL aiding effort to mitigate repeaterinterference to military radars
by Edward Cole 25 Apr '07

25 Apr '07

Yeah, I thought about that. If your antenna has 20-dB gain, like my eme array has, it has a 3-dB beamwidth of 20-deg. So at elev. 20 I could transmit 10w and only have 5w on the horizon. Restricting my satellite operation above 20-deg. would be needed. If you ran 25w, you would be restricted to above 40-deg. But didn't someone say that most satellite passes are below 40-degrees? How many folks use eme arrays for satellites? Now if you uplink on 5.7 GHz with a 3-foot dish then beamwidth is 4-deg. with 33-dB gain. Your EIRP is 5w x 2000 = 10 kw ...kind of shows the advantages of mw for space comm. I know I have definitely gone off topic...but it gives one something to think about. 73 Ed At 07:36 AM 4/24/2007, Margaret Leber wrote: >On 4/24/07, Edward Cole <kl7uw(a)acsalaska.net> wrote: > >>Build satellites that require no more than 5w EIRP from the ground >>station may be the only answer. > >Or transmit with a more directional antenna aimed skyward...which is >not a practical solution for terrestrial repeaters. > >-- >73 de Maggie K3XS >Editor, Phil-Mont Mobile Radio Club Blurb - http://www.phil-mont.org >Elecraft K2 #1641 -- AOPA 925383 -- ARRL 39280 73, Ed - KL7UW ====================================== BP40IQ 50-MHz - 10-GHz www.kl7uw.com 144-EME: FT-847, mgf-1801, 4x-xpol-20, 185w DUBUS Magazine USA Rep dubususa(a)hotmail.com ======================================

2 1

DTMF mike for IC-910
by Tim Tuck 25 Apr '07

25 Apr '07

Hi all, My shiny new 910 arrived yesterday and I've been having all sorts of fun working it out ! In looking at available options one thing that I couldn't find was a DTMF mike. Is there one available either third party or one from a different Icom rig that will work on the 910 ? I though I'd ask here first since there seems be a lot of 910 owners here :) Any info, with product numbers if possible, will be gratefully received. thanks Tim -- VK2XTT :: BMARC :: WIA :: AMSAT :: QF56if =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Scanned with Copfilter Version 0.84beta1 (ProxSMTP 1.6) AntiVirus: ClamAV 0.90.1/3158 - Wed Apr 25 08:36:50 2007 by Markus Madlener @ http://www.copfilter.org =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Scanned with Copfilter Version 0.84beta1 (ProxSMTP 1.6) AntiVirus: ClamAV 0.90.1/3158 - Wed Apr 25 08:36:50 2007 by Markus Madlener @ http://www.copfilter.org

2 1

FW: ARLB013 ARRL aiding effort to mitigate repeater interference to military radars
by tjjapha＠earthlink.net 24 Apr '07

24 Apr '07

Hi All, Should this ARRL msg. cause us to worry about the future of mode B operations? 73, Tony, N2UN > [Original Message] > From: ARRL Web site <memberlist(a)www.arrl.org> > To: <tjjapha(a)earthlink.net> > Cc: <Subscribed ARRL Members:> > Date: 4/24/2007 12:06:01 AM > Subject: ARLB013 ARRL aiding effort to mitigate repeater interference to military radars > > SB QST @ ARL $ARLB013 > ARLB013 ARRL aiding effort to mitigate repeater interference to > military radars > > ZCZC AG13 > QST de W1AW > ARRL Bulletin 13 ARLB013 > From ARRL Headquarters > Newington CT April 23, 2007 > To all radio amateurs > > SB QST ARL ARLB013 > ARLB013 ARRL aiding effort to mitigate repeater interference to > military radars > > The ARRL has been working with the US Department of Defense to > develop a plan to mitigate alleged interference from 70 cm ham radio > repeaters to military radar systems on both coasts. Citing an > increasing number of interference complaints, the US Air Force has > asked the FCC to order dozens of repeater systems to either mitigate > interference to the ''PAVE PAWS'' radars in Massachusetts and > California or shut down. Amateur Radio is secondary to government > users from 420 to 450 MHz and must not interfere with primary users. > The Commission has not yet responded. ARRL Regulatory Information > Specialist Dan Henderson, N1ND, stresses that the Defense Department > acknowledges Amateur Radio's value in disasters and emergencies and > is being extremely cooperative, and a wholesale shutdown of US 70 cm > Amateur Radio activity is not in the offing. > > ''The ARRL Lab is working up calculations on each repeater system the > Air Force has identified to determine where interference-mitigation > techniques offer a reasonable chance of keeping the repeater on the > air,'' Henderson says. > > The situation affects 15 repeaters in the vicinity of Otis Air Force > Base on Cape Cod, Massachusetts, and more than 100 repeaters within > some 140 miles of Beale Air Force Base near Sacramento, California. > > A US Air Force contractor identified the problematic repeater > systems last summer, but the situation didn't become critical until > the Air Force contacted the FCC a month ago. ARRL officials met with > Defense Department representatives in late March to discuss alleged > interference to the PAVE PAWS radar sites. Henderson has contacted > Amateur Radio frequency coordinators in both affected areas. > > PAVE PAWS is a missile and satellite detection and tracking system, > and its facilities occupy essentially the entire 70 cm band -- one > factor that makes mitigation difficult. As a ''first step,'' however, > the ARRL is recommending that all affected repeater owners reduce > power -- possibly to as little as 5 W effective radiated power > (ERP). > > ''We understand the difficulty this may cause to owners and users,'' > Henderson said, ''but the alternative to operating with a smaller > coverage area may be not operating at all.'' > > Henderson says the League is still seeking further information on > the problem. ''Until the Defense Department accepts a mitigation > plan, repeater owners should exercise patience,'' he cautioned. > > Contact Dan Henderson, N1ND, n1nd(a)arrl.org, or 860-594-0236, with > specific questions or issues associated with this situation. > NNNN > /EX

6 6

Re: FW: ARLB013 ARRL aiding effort to mitigate repeaterinterference to military radars
by Tony Langdon 24 Apr '07

24 Apr '07

At 03:20 AM 4/25/2007, Nate Duehr wrote: >Proof positive that a reasonable solution can probably be found. > >The Amateur allocation in the UHF band is a Primary allocation of the >US Military in the US, with the specific wording in the NTIA >documentation stating the military is to "treat Amateurs as Primary". Well, the military over here as well have certainly been more of a friend than a foe. Our biggest dangers these days are not from the military, but from unlicensed gadgets, which have been approved for use in the 433 - 434 MHz band. What made this a really nasty problem is that the authorities put few limits on the emission types, leading to cordless headphones, crane controllers (nasty potential for OHS implications here) and other high duty cycle devices on the band. Wlesr, this happens to be about 80-90% of the available repeater inputs. Because of the duty cycle, CTCSS is not a solution, all you end up is a bunch of "deaf" repeaters that takes a kW to open. Had the devices been limited to low duty cycle applications, CTCSS would have been enough to prevent the occasional "blip" from someone's wireless doorbell opening up the repeater. Oh, and as for satellites, well some of the cheap junk could drift into the 435 MHz region. I already know of some cordless headphones that drift as high as 434.900, which is outside the allocated band for these devices. These get into a repeater which was moved outside the affected band to get away from the problem. Oh, and interference from these devices "does not exist", as far as the legislation goes. It's actually written into the LCD (confirmed, I have read the clause myself). The flip side of this madness is it is nigh on impossible to find a wireless doorbell or weather station that will work reliable in my environment. They use SAW filters in their receivers, and these get severely desensed by ANY 70cm transmissions, even the repeater output, 5 MHz away. The older 304 MHz stuff is much better for my uses. :) Some new inputs (with an odd 5.4 MHz split) have been opened up to try and alleviate the problem with the repeaters, but it's a hack to work around the mess the authorities have given us. Give me the military anytime to share the band with, they play ball much nicer than the rabble and the profiteers that feed them. :) 73 de VK3JED http://vkradio.com

1 0