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Having looked at this Mission Overview PDF, I would have covered both EchoStar 19/Jupiter 2 and the first Falcon 9 Iridium mission on the same day had the latter not been delayed.

I doubt it was possible for US ranges to support both.
General Discussion / Re: John Glenn has passed away.
« Last post by Perchlorate on Today at 12:46 AM »
We pause to honor this fine man at the end of his well-lived life....
We have looked at these types of transistors before. I picked up one of these for $104:

If they were available mounted on a finished board that only required soldering power leads, heat sink, and plugging in the coax, that would be even better! 

Very soon the manufacturers of LDMOS transistors will be offering a full board, including also the frequency generator capable of being computer controlled in phase and frequency:

These are cool. NOT. They are specified as fairly narrow band devices, to comply with ISM standards when mounted on the board (i.e., you're almost, but not quite, tuning the frustum to the source). They require tens of amps of clean direct current (beware of Lorentz forces). Their efficiency is comparable to a magnetron, so expect to shed several HUNDRED watts of heat. A magnetron is a vacuum tube, and tolerates the heat. A solid state transistor, whether LDMOS like this one or GaN like the Macom device, nah, not so much. These devices are presented on evaluation boards optimized for a 50 ohm source and load for evaluation purposes. A frustum is not a 50 ohm load. S-parameters are strictly for linear purposes normalized to the network impedance. Beware S-parameters for non-linear devices launched into non-normalized conditions. Finally, these are amplifiers, not oscillators. They have a certain gain, at a certain frequency. You still have to drive them with a source of somewhere on the order of 4 watts of microwave RF. Keep in mind that the microstrip design of these protoboards radiates an E field quite well.

Be safe. If you buy one of these devices, and build one of these amplifiers, and don't enclose it in a well shielded RF tight enclosure, you can expect to wake up the next morning with eyeballs that look like poached eggs. Forever. As a test, over-ride the interlocks on your microwave oven, stick your head inside, and turn it on medium for one minute. Don't do this. But do contemplate the result.

A magnetron power supply will kill you, no questions asked, right now and right away just from the voltages and currents involved. A high power RF transistor may not shock you to death instantly, but will do so insidiously, and it most certainly can cook you or burn you to death. Or put you into a condition where you wished you were dead.
General Discussion / Re: John Glenn has passed away.
« Last post by catdlr on Today at 12:30 AM »
RIP and God bless you John Glenn.   

For those who want to re-visit John's last trip to space....

STS-95 Mission Highlights


Published on Dec 8, 2016
On Oct. 29, 1998, astronaut and U.S. Senator John Glenn launched as a payload specialist aboard space shuttle Discovery on mission STS-95 as part of a seven-person crew including Commander Curtis Brown, Pilot Steven Lindsey, Mission Specialists Scott Parazynski, Stephen Robinson and Pedro Duque, and Payload Specialist Chiaki Mukai. At the age of 77, Glenn was the oldest person to date to fly in space. During the nine-day mission, Glennís presence on the flight provided valuable data on how weightlessness affected him compared to his experience 36 years earlier on his Friendship 7 flight. Medical data also gathered on the effects of spaceflight and weightlessness on the elderly. Mission objectives included a variety of science experiments, the deployment and retrieval of the Spartan free-flyer payload, and operations with the Hubble Space Telescope Orbiting Systems Test (HOST) and the International Extreme Ultraviolet Hitchhiker payloads.

General Discussion / Re: John Glenn has passed away.
« Last post by DecoLV on Today at 12:20 AM »
The simple honor and decency of the man makes one wish everyone could be like him.
Interesting post on .
A S50 stage might be test fired in January 2017.
A VS-50 sounding rocket (most likely a single stage) might launch during November.

VLM-1 was excluded from the 2016 micro launcher list. (Actually not, ssc: sso express) But in my view VLM-1 is one of the most  rigid supported micro launcher developments, being backed by two or three nations.
Suggest the talking/thinking conspiracy/"tin foil"/other hats ... simply don't belong ... anywhere.

They'll launch when they launch.
General Discussion / Re: John Glenn has passed away.
« Last post by Cherokee43v6 on Today at 12:06 AM »
Godspeed Sir.  Thank you for inspiring our dreams.

I still believe that NASA missed a golden opportunity by not painting a big red 7 through shuttle Discovery's name when he flew on her.
General Discussion / Re: John Glenn has passed away.
« Last post by JAFO on 12/08/2016 11:53 PM »
Higher, ever higher.
 "Arriba, siempre arriba" ó  Georges Chavez

With Ted Williams, K3 AFB Korea, 1953:
That is one impressive launcher! I hope Japan keeps on improving and upgrading their line.
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