AMSAT 發表 M2 衛星天線

AMSAT 發表 M2 衛星天線

2017-02-07

BM2CAJ

BX2ADJ

http://store.amsat.org/catalog/product_info.php?cPath=1&products_id=123

AMSAT-NA and M2 Antenna Systems LEO-Pack Back in Stock in AMSAT StoreAMSAT-NA and M2 Antenna Systems are pleased to announce that the LEO-Packsystem is being offered to members only at $499, shipping included (US only).Non-members can join AMSAT-NA at time of purchase to participate in thisspecial purchase.The LEO-Pack will then be drop shipped to the purchaser from M2, who estimatesthat the production time after the order is received will be 2-3 weeks.The 436CP16 and 2MCP8A are light weight, circularly polarized antennasoptimized for Low Earth Orbit (LEO) Satellite communications or otherapplications where a small circular polarized antenna is required. Optimummatch and gain designed for the satellite band.Rear mounted for easy coaxial cable routing. A preamp (not included) can bemounted close to the antenna for almost no coax loss before the preamp,maximizing your receive performance.See all the details, including links to technical specifications at:
http://store.amsat.org/catalog/product_info.php?cPath=1&products_id=123


[ANS thanks the guys in the AMSAT On-Line Store for the above information]

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BM2CAJ

BX2ADJ


BU2DR

73

AMSAT 發表 M2 衛星天線

AMSAT 發表 M2 衛星天線

http://store.amsat.org/catalog/product_info.php?cPath=1&products_id=123

AMSAT-NA and M2 Antenna Systems LEO-Pack Back in Stock in AMSAT StoreAMSAT-NA and M2 Antenna Systems are pleased to announce that the LEO-Packsystem is being offered to members only at $499, shipping included (US only).Non-members can join AMSAT-NA at time of purchase to participate in thisspecial purchase.The LEO-Pack will then be drop shipped to the purchaser from M2, who estimatesthat the production time after the order is received will be 2-3 weeks.The 436CP16 and 2MCP8A are light weight, circularly polarized antennasoptimized for Low Earth Orbit (LEO) Satellite communications or otherapplications where a small circular polarized antenna is required. Optimummatch and gain designed for the satellite band.Rear mounted for easy coaxial cable routing. A preamp (not included) can bemounted close to the antenna for almost no coax loss before the preamp,maximizing your receive performance.See all the details, including links to technical specifications at:http://store.amsat.org/catalog/product_info.php?cPath=1&products_id=123

[ANS thanks the guys in the AMSAT On-Line Store for the above information]

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2017-02-06

銥衛星閃光 (銥閃) Iridium Flare 再過幾年就沒了--要看要快

銥衛星閃光 (銥閃) Iridium Flare 再過幾年就沒了--要看要快

2017-02-03

據報導，銥衛星已由 Space X 部署第二代衛星，第一代衛星會逐漸淘汰，再過幾年就沒得看銥閃了。

BM2CAJ

BX2ADJ

BU2DR

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Get Your Iridium Fix Before It’s Too Late!

The shock and dazzle of Iridium flares will soon be a thing of the past.
Here's how to make the most of seeing them before a new generation of spacecraft
replaces the Iridium satellites.

Each of the approximately 66 Iridiums in orbit have three door-sized
aluminum antennae treated with highly reflective, silver-coated Teflon for
temperature control.

When the angle between observer and satellite is just right, sunlight
reflecting off an antenna can cause the satellite to surge from invisibility up to
magnitude –8.5 in a matter of seconds. If you've never seen one, the searing
brilliance may make you recoil instinctively. On rare occasions, flares can
reach magnitude –9.5. That's 100 times brighter than Venus!

Sadly, that era will soon draw to a close. On January 14th, SpaceX’s
Falcon 9
delivered the first 10 of a new generation of Iridium NEXT satellites to
low-
Earth orbit, starting the process to replace the older units in a maneuver
called slot-swapping. While the new birds will provide faster data rates and
enhanced global communications, their antenna design is completely
different and not expected to produce significant flares.

Heavens Above is one of the easiest sites to get you looking in the
right place at the right time. The Heavens Above website allows for easy figuring and
finding of Iridium flares.

Just sign in and give it your location, then click the Iridium Flares
link under the Satellites heading on the left side of the homepage. A table will
pop open with a week's worth of passes that includes pertinent information like
brightness, altitude, and magnitude of the flare at flare center, the
brightest possible magnitude for a particular pass. Clicking on the date will
produce a map showing the flare's path and ground track where the flare will appear
brightest. When that path passes near or over your location, you'll see a –8
dazzler. If not, you can use the map to drive to the sweet spot and
await the display.

The transition to the Iridium NEXT generation will be gradual but
certain, so make the most of the opportunities that remain. If you're a teacher, do your
homework and plan an outing to show a daytime flare to your science class.
Anything that gets people talking more about the sky is a good thing, and I
guarantee those kids will never forget the sight.

[ANS thanks Bob King, and Sky and Telescope for the above information]

73