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WA7PBE
04-17-2014, 06:26 PM
So as a new ham I was looking at the frequency allocation chart on the DOC website (http://www.ntia.doc.gov/files/ntia/publications/spectrum_wall_chart_aug2011.pdf) and noticed that above 1GHz there are quiet a few bands allocated to amatuers. What typicaly are these bands used for?

WØTKX
04-17-2014, 06:37 PM
There are a few repeaters "way up there" in certain areas. Sometimes also used as data links, such as between repeaters on lower frequencies. There is a little bit of activity on SSB and CW as well, especially during contests.

NQ6U
04-17-2014, 08:30 PM
Also, a sement of the frequencies around 2.4 GHz allotted to Wi-Fi fall within the amateur radio bands, so some hams have hotrodded Lynksys WRT54G routers with firmware changes, amplifiers and high-gain antennas (not allowed unless you are a ham) to set up wide area HSMM networks.

W3WN
04-18-2014, 09:26 AM
Frankly (hi Frank!, wherever you are), Amateurs as a whole don't make much use out of the bands above 23 cm. There are a lot of reasons for that, which I don't want to delve into right now.

Suffice to say, we have a lot of spectrum we COULD use, and most of it we DON'T use.

The HSMM is a start. I wanted to do something like that years ago, but the technology, specifically affordable technology, available to the average person (I'm average?) just wasn't there.

Personally, I'd love to see something like this...

Using our microwave Amateur-Satellite Service allocations, set up three geosynchronous OSCARs , positioned such that we theoretically would have complete worldwide coverage. On each geo-OSCAR, have one transponder that would cover the area of the world below it. Each would also have a transponder to link to the bird to it's "left", another to it's "right" -- relay most likely through a ground command station if they're not in line-of-sight. And if possible, one more transponder that would relay at the same time to both of the other birds.

[If this becomes possible, there would also be other transponders covering different A-SS bands... yeah, I know the initials come out funny, let's make that AmSatServ instead... redundancy and all that fun stuff... just hold that thought for the details, right now I'm just going over the concept]

Now, if this works... imagine (depending on the transponder bandwidth) anywhere from a 5 MHz to a 25 MHz band that you'd use just for, say, inter-continental communications. Another one to talk to someone on the bird east; another the bird west; and even one that would be worldwide. Only delays would be in the time it took for the signal to go up & down, and (if relayed through ground) around.

That's more bandwidth on one transponder than we have right now on all of HF, including 160. Imagine this... complete worldwide coverage, at all times.

So why hasn't it been done? We all know the answers to that one as well. Two words: Money. Politics.

It costs money to design and build the birds, and to meet the specs that the Government requires to make sure they'll last up there for years. It costs money to launch the birds. A lot of money.

Politically, you have to deal with administrations around the world that aren't always that friendly to Amateurs, and who might wonder about what the birds are REALLY for. Plus, there's only so much "room" in the geo-sync orbital belts, and the satellites up there have to be positioned a certain safe distance apart. So even if we could afford to build & launch the birds, there's no guarantee of a "parking spot" for them.

Every few years, you hear someone talk about getting a satellite system to "donate" space on board a bird for an Amateur (AmSatServ) band transponder. Haven't heard of one actually happening yet, but it takes time.