I know quite a few hams with access to this equipment. It's fairly easy to put together a satellite station, including dsp for demodulating various encoding methods. Hacking wireless data streams has been going on for the last 20 years, it just isn't as mainstream as say, hacking AOL. There is readily available code on the net for decoding all kinds of data streams, and as for LEO's moving... yeah, they move. Thats what az-el rotators are for. Again, you can buy one for under $1000, or build one out of a couple of cheap TV rotators. Hook that up to a controller, fire up your favourite tracking package and away you go. The element sets for most non-military satellites are readily available.
Simple satellites such as the NOAA apt satellites are easy to receive and demodulate, and Monitoring Times had a nice article on decoding (by hand) Russian satellite telemetry.
It isn't a matter of anything but time, and a desire to do it for the sake of doing it. My advice? Use encryption. Strong encryption.
Keplerian Elements for most satellites, links for tracking packages, and telemtry decoding packages are available at celestrak, as well as many other places:
Also, just as a totally useless aside, looking at my handy-dandy (three or so years old) frequency chart I have here, I find it interesting that that portion of spectrum used to be for amateur radio operators. Co-located, perhaps, or did they just take it away from the amateurs altogether?
It is still an amateur allocation. I believe part 15 devices (such as wap and cordless phones) are a tertiary allocation.
That band is used by amateurs. As a matter of fact, there was a recent incident involving an apartment building wired for 802.11 that was interfering with some amatuer use of the band. Another reasonb why you don't want to increase your output power without reason. All of this stuff can work together just fine as long as people realize that if 10mW does the job, you don't need to be running 1W of output power.
FCC QUERIES WIRELESS 'NET PROVIDER ABOUT INTERFERENCE TO HAMS
The FCC has asked a wireless Internet system provider what it intends to do
to eliminate interference to Amateur Radio operations in the Dallas, Texas
area. The FCC wrote Darwin Networks Inc on February 8, 2001, regarding
complaints of harmful interference to Amateur TV on 2.4 GHz that's said to
be a result of the company's deployment of Part 15 devices in an apartment
complex.
They are leased. A company I worked at being a good example. A lot of people thought everyone having an aeron chair was silly and a waste of money. So instead, they leased them for $25 per chair per year. Top that off with the cost of the chair negotiated down to $465... compare that to any other ergonomic chair and it is pretty much the same. So, yes, companys that purchase them are stupid but all in all it is a bad metric.
And now those orchards are largely gone. It's sad, because when you come "home" you are supposed to see things that bring back memories... and one thing I remember, were the orchards near San Jose.
I fully agree. And the sad thing is, the people working for dot-coms actually think they matter. Everyone needs to eat, yet who provides the food? Surely not the dot-commers, it's the hard working middle-class families and migrant farm workers. Do they make a living wage? Absolutely not. Does the marketing hack who couldn't code his way out of a paper bag? You betcha. And then some.
Silicon Valley is the shining example of the failure of capitalism, capitalism gone awry. The difference between communism and capitalism? You know when communism has failed.
Methinks someone needs to smack the stock-option millionaire MBA types and remind them of where they came from, where they could be going, and upon whose backs they are making all of thier money.
"If the only way to judge success is through cash flow, then I don't know. I can do anything with my life but I probably won't." -- SF band Grotus, "Hand Job" from Mass (London Records)
hehehe. cool, thanks. looked them up in a recent copy of the allied catalog and they have them listed as CPC connectors... maybe that is redundant and stands for 'Cannon Plug Connector'.:)
when i was at broderbund about 8 years ago, they had a studio for recording vocals that had the machines isolated in a seperate room. all interconnections were bussed in through the wall using high-desnity connectors (forget the designator for these, but they were much like the high-density round military connectors that on the outside look like screw-on pvc connectors). it worked well and completely eliminated all noise in the studio.
it was a really beautiful space, too. anyways, my point is, you could probably very easily design your own system to isolated the machines either in a seperate room, or in some kind of damping chamber, much like the acoustic covers for old dot matrix printers.
Because it won't neccessarily draw the general public's attention to Linux, but will serve as a step in helping to make Linux a more apparently viable platform for console gaming, and anything else for that matter. It's almost like promoting Linux in order to promote Linux if that makes sense. Get a game machine, a _good_ game machine, out into the market using Linux, let us geeks see how good it is, and let the snowball effect kick-in. Who knows. Maybe a few years from now, all the console boxes will be running Linux...
I worked for a company for a very long time that is responsibility for a very well known and uqiquitous browser plug-in that actually used the browser plug-in to accomplish kind of the same thing. Before the plug-in, lot's of people used titles developed with thier authoring app but never actually new about them. Now, since the plug-in, almost everyone has heard of them. They give the plug-in away for free, and use the built-in advertising (conceptually, they don't actually display ads!) to leverage thier authoring tools. The end-result being very good, at least from a finacial standpoint.:)
...simply because it is a rather interesting glimpse of our own reality through science-fiction eyes if you will. take for example, computers, or better yet, the internet. science fiction authors have discussed the same type of thing, and people read it and thought 'wow, that is neat, but i wonder if it will ever happen'.
i may be getting confused in my old age, but didn't count zero by w. gibson have a hobbyist character who experimented with genetic engineering? looks like that is becoming a reality.
all i can say is, cool. albeit scary at the same time.
The amateur station aboard Mir (R0MIR) has been transmitting Slow-Scan Television (SSTV) for the past 6 months or so. Check out the following links for some great images received from the station (the second link includes a lot of links to other archives of Mir SSTV images):
The cool thing about SSTV from Mir is that it is largely controlled by the station operators aboard , and is much more dynamic content-wise than stuff like weather satellites and stuff. They occasionally turn the camera on themselves, visiting shuttles, etc. Check it out, it's neat stuff. It is also fairly easy to receive and decode SSTV transmission using a soundcard, some freeware code and a radio capable of receiving the 2-meter amateur band. The following link has lots of info on SSTV (aside from the blink tags):
Just a simple statement: generally, with digital transmissions, the higher the bandwidth, the wider the signal. So, that being said, 10Mb on 2.4Ghz is a relatively wide signal, and is going to step on stuff. This is the pandora's box of "everything" going wireless. It won't be solved until more and more devices incorporate "software radio" techniques and know how to back-off of an active channel. Then, more, but never an infinite or even close, number of devices will be able to co-exist.
This is a classic problem. There is only so much [currently] usable spectrum.
BTW, sheilding has very little to do with it. It affects it some, and can cause co-channel interference, but the bigger problem is the fact that a 10Mb signal is _very wide_.
Current ELF systems do not use morse, and as a matter of fact, are not CW-based systems at all. They are low-speed data systems using something more like FSK than anything else. There is a lot of low-fer (as they are reffered to) activity down there (we are talking the 150kHz band here) that utilizes extremely slow-speed CW for experimental communications. A common example of LF data transmission is the "RF Controlled Atomic Clock" on your desk. It receives the LF data stream from WWVB (for us folks in the U.S.) and gathers the neccessary info to set your clock.
And the noise issue is a rather large one, which LF transmission are particularly prone to, much like the audio band (20-20kHz), and from some of the same sources (lightning strikes, natural radio, etc).
I think the biggest problem is with environmental and ecological concerns. As far as gee-whiz factors are concerned, it is kind of neat, but aside from that, the impact on species exposed to it is by far a more important issue than whether or not submariners should get thier e-mail. Submarines are one of those places where maybe people just shouldn't have net access... but then again, I feel that way about most politicians too.:)
Cable modem and wireless LAN are encrypted, and I see no reason why this wouldn't be, too. The encryption isn't very strong (40 or 56 entropy bits RC5, or something like that) but it's enough to keep the neighbor from tcpdump'ing one's connections, at least in real time.
umm, that is not neccessarily true. a lot of early wireless lan products, and quite a few on the market today, are _not_ encrypted. the newer, forward thinking products, fortunately, are.
you'd be amazed at how insecure wireless data systems actually are. when you are reading the specification for something and you run across the statement "the technical knowledge and equipment neccessary to intercept and decode this system is out of reach of the average person, making this an extremely secure system" it makes you scratch your head. this was [paraphrased] from the mobitex specification, which requires a handful of parts from radio shack and a bit of software.
be wary of _any_ wireless data product that does not implicity state it uses encryption, and states what the encryption algorithm is. a lot of protocols use something called 'bit scrambling' to maintain data integrity, and the marketing types always confuse this with encryption.
well, actually, it can go very far. do a search sometime for 'qrp' on the net. it's sort of an amateur radio sub-culture. i routinely work the continental united states at 500mW, and there are people running microwatts as well. output power is only a small part of it. the length of the antenna and frequency in question contributes more.
basically, they will need to do a lot with ensuring compliance of the electrical wiring in homes to minimize interference with licensed users of radio spectrum. i routinely find spurious emmisions from all kinds of household devices (including home networking stuff) all over the shortwave band, and occasionally up into the vhf band as well.
do you think the 'main-streaming' of political activism, combined with the splintering of historically 'left-wing' ideologies has caused credibility to be lost for activism in general? do you think that the ease of access and publication on the internet has lent itself to this loss of credibility, if it exists at all? it seems that the media, at least in certain markets, has turned a deaf or apathetic ear towards any type of political activism that is not clearly mainstream. do you think the internet, and activism in general, can turn this around?
it actually has not declined as much as one would think. and would you really want to take away the spectrum used for experimentation? the same experimentation that has led to some of the wireless technologies you take for granted? it has much in common with the open-source movement, and in the grand scheme of things, amatuers have _very little_ spectrum allocated to them. if you want spectrum for ip, go after the allocations held (and underutilized) by the railroad industry and the military.
amateur radio still has it's benefits and is still a much valued service/endeavor. after all, what is more fun than converting an old radar detector into a 10Ghz 25mW fm transceiver?:)
considering that the rim950 with service from bell south doesn't use any encryption, it doesn't really matter now, does it?
seriously, i figured they would be using encryption but running a dsp and decoding it as plain old mobitex works fine. granted, you get all the other crud on the mobitex network but if you filter for the man # you want it shouldn't be an issue.
and they said the same thing about mdt's. rember, bit scrambling is _not_ encryption, it's a data integrity mechanism...:)
The service is generally provided via MOBITEX by Bell South Wireless Data and a few other providers. I like my RIM pager, and it doesn't "redirect" e-mail like someone mentioned (might have been the way they were set up). The only major problem with RIM pagers is they are NOT SECURE. You can decode the messages rather easily off-the-air.
so, now that this has been done, how long until some of the amateur sats in orbit have this capability? with the launch of phase-3d, with its reprogrammable modems and modules, maybe we will have something to play with.
i am actually suprised this wasn't done earlier with amateur satellites, as it is (aside from the issues involving communication with orbiting communications systems) just a wireless network connect. if the satellite was in polar orbit you'd have availability problems, but a sat in the clarke belt would be nifty.
anyone know of plans in the amateur community to do this?
oh, and check out AmSat for info on amateur satellites and whatnot.
i currently get my network connections using freewave data tranceivers. they are NOT cheap, and are only 115kBps, but they will go up to 30+ miles line of site with external high-gain antennas. these are the same tranceivers used in various remote data acquisition applications. the advantage being they act as modems, and can emulate a hayes modem making them usable in many applications. my current link is runnin 100mW to 10dB yagis.
the problem with external antennas on wireless ethernet devices is the FCC requires you to purchase the antenna from the same vendor as the actual tranceiver in order to maintain compliance with part 15 rules. purchasing a seperate antenna is totally doable, but if you cause _any_ interference and the system is deemed to not be in compliance with part 15 rules, you face fines and confiscation of equipment.
personally, i think a more pure approach to zen is more appropriate and can be applied to anything, not just code. people who are interested should check out 'zen mind, beginner's mind' by shunryu suzuki (isbn 0-8348-0052-7) of the soto school. he is the founder of zen temple san francisco. very good, and for me, invaluable.
Well, I think that her discovery was simply a different approach. This happens ALL THE TIME in scientific research. Sometimes you can't see the forest from the trees when you are buried. It sometimes takes someone without any experience to try something no one else has even considered. So I will give her the benefit of the doubt, for the time being.
After all, the CRC tables [Chemical Rubber Corp book of tables] had to be recalculated in the seventies when a 14 year old discovered they were all wrong.
Slashdot Mirror
I know quite a few hams with access to this equipment. It's fairly easy to put together a satellite station, including dsp for demodulating various encoding methods. Hacking wireless data streams has been going on for the last 20 years, it just isn't as mainstream as say, hacking AOL. There is readily available code on the net for decoding all kinds of data streams, and as for LEO's moving... yeah, they move. Thats what az-el rotators are for. Again, you can buy one for under $1000, or build one out of a couple of cheap TV rotators. Hook that up to a controller, fire up your favourite tracking package and away you go. The element sets for most non-military satellites are readily available.
Simple satellites such as the NOAA apt satellites are easy to receive and demodulate, and Monitoring Times had a nice article on decoding (by hand) Russian satellite telemetry.
It isn't a matter of anything but time, and a desire to do it for the sake of doing it. My advice? Use encryption. Strong encryption.
Keplerian Elements for most satellites, links for tracking packages, and telemtry decoding packages are available at celestrak, as well as many other places:
http://www.celestrak.com
Also, just as a totally useless aside, looking at my handy-dandy (three or so years old) frequency chart I have here, I find it interesting that that portion of spectrum used to be for amateur radio operators. Co-located, perhaps, or did they just take it away from the amateurs altogether?
It is still an amateur allocation. I believe part 15 devices (such as wap and cordless phones) are a tertiary allocation.
That band is used by amateurs. As a matter of fact, there was a recent incident involving an apartment building wired for 802.11 that was interfering with some amatuer use of the band. Another reasonb why you don't want to increase your output power without reason. All of this stuff can work together just fine as long as people realize that if 10mW does the job, you don't need to be running 1W of output power.
Excerpt from the ARRL Letter, Volume 20 Number 7
FCC QUERIES WIRELESS 'NET PROVIDER ABOUT INTERFERENCE TO HAMS
The FCC has asked a wireless Internet system provider what it intends to do
to eliminate interference to Amateur Radio operations in the Dallas, Texas
area. The FCC wrote Darwin Networks Inc on February 8, 2001, regarding
complaints of harmful interference to Amateur TV on 2.4 GHz that's said to
be a result of the company's deployment of Part 15 devices in an apartment
complex.
They are leased. A company I worked at being a good example. A lot of people thought everyone having an aeron chair was silly and a waste of money. So instead, they leased them for $25 per chair per year. Top that off with the cost of the chair negotiated down to $465... compare that to any other ergonomic chair and it is pretty much the same. So, yes, companys that purchase them are stupid but all in all it is a bad metric.
And now those orchards are largely gone. It's sad, because when you come "home" you are supposed to see things that bring back memories... and one thing I remember, were the orchards near San Jose.
And they are gone. Makes me sad.
I fully agree. And the sad thing is, the people working for dot-coms actually think they matter. Everyone needs to eat, yet who provides the food? Surely not the dot-commers, it's the hard working middle-class families and migrant farm workers. Do they make a living wage? Absolutely not. Does the marketing hack who couldn't code his way out of a paper bag? You betcha. And then some.
Silicon Valley is the shining example of the failure of capitalism, capitalism gone awry. The difference between communism and capitalism? You know when communism has failed.
Methinks someone needs to smack the stock-option millionaire MBA types and remind them of where they came from, where they could be going, and upon whose backs they are making all of thier money.
"If the only way to judge success is through cash flow, then I don't know. I can do anything with my life but I probably won't." -- SF band Grotus, "Hand Job" from Mass (London Records)
But personally, PETA should be 'peta.org' not 'peta.com'. The parody site should be 'peta.com'. Why don't they just swap domains?
/dev/null.
Last time I checked, PETA was a non-profit. But then again, as someone else mentioned, net standards don't mean anything anymore...
Just my opinion. Flames to
hehehe. cool, thanks. looked them up in a recent copy of the allied catalog and they have them listed as CPC connectors... maybe that is redundant and stands for 'Cannon Plug Connector'. :)
:)
learn something new everyday.
when i was at broderbund about 8 years ago, they had a studio for recording vocals that had the machines isolated in a seperate room. all interconnections were bussed in through the wall using high-desnity connectors (forget the designator for these, but they were much like the high-density round military connectors that on the outside look like screw-on pvc connectors). it worked well and completely eliminated all noise in the studio.
it was a really beautiful space, too. anyways, my point is, you could probably very easily design your own system to isolated the machines either in a seperate room, or in some kind of damping chamber, much like the acoustic covers for old dot matrix printers.
Because it won't neccessarily draw the general public's attention to Linux, but will serve as a step in helping to make Linux a more apparently viable platform for console gaming, and anything else for that matter. It's almost like promoting Linux in order to promote Linux if that makes sense. Get a game machine, a _good_ game machine, out into the market using Linux, let us geeks see how good it is, and let the snowball effect kick-in. Who knows. Maybe a few years from now, all the console boxes will be running Linux...
:)
I worked for a company for a very long time that is responsibility for a very well known and uqiquitous browser plug-in that actually used the browser plug-in to accomplish kind of the same thing. Before the plug-in, lot's of people used titles developed with thier authoring app but never actually new about them. Now, since the plug-in, almost everyone has heard of them. They give the plug-in away for free, and use the built-in advertising (conceptually, they don't actually display ads!) to leverage thier authoring tools. The end-result being very good, at least from a finacial standpoint.
...simply because it is a rather interesting glimpse of our own reality through science-fiction eyes if you will. take for example, computers, or better yet, the internet. science fiction authors have discussed the same type of thing, and people read it and thought 'wow, that is neat, but i wonder if it will ever happen'.
i may be getting confused in my old age, but didn't count zero by w. gibson have a hobbyist character who experimented with genetic engineering? looks like that is becoming a reality.
all i can say is, cool. albeit scary at the same time.
The amateur station aboard Mir (R0MIR) has been transmitting Slow-Scan Television (SSTV) for the past 6 months or so. Check out the following links for some great images received from the station (the second link includes a lot of links to other archives of Mir SSTV images):
http://www.qsl.net/wb8erj/mir-pix.htm
http://home.t-online.de/home/mrensen/m ir.htm
The cool thing about SSTV from Mir is that it is largely controlled by the station operators aboard , and is much more dynamic content-wise than stuff like weather satellites and stuff. They occasionally turn the camera on themselves, visiting shuttles, etc. Check it out, it's neat stuff. It is also fairly easy to receive and decode SSTV transmission using a soundcard, some freeware code and a radio capable of receiving the 2-meter amateur band. The following link has lots of info on SSTV (aside from the blink tags):
http://www.mbnet.mb.ca/~rraimb/
note to self, read more before posting. same thing
was said much more thoroughly and eloquently by
others. bad cvoid. bad.
Just a simple statement: generally, with digital
transmissions, the higher the bandwidth, the wider
the signal. So, that being said, 10Mb on 2.4Ghz is
a relatively wide signal, and is going to step on
stuff. This is the pandora's box of "everything"
going wireless. It won't be solved until more and
more devices incorporate "software radio" techniques and know how to back-off of an active
channel. Then, more, but never an infinite or even close, number of devices will be able to co-exist.
This is a classic problem. There is only so much [currently] usable spectrum.
BTW, sheilding has very little to do with it. It
affects it some, and can cause co-channel interference, but the bigger problem is the fact
that a 10Mb signal is _very wide_.
Current ELF systems do not use morse, and as a matter of fact, are not CW-based systems at all. They are low-speed data systems using something more like FSK than anything else. There is a lot of low-fer (as they are reffered to) activity down there (we are talking the 150kHz band here) that utilizes extremely slow-speed CW for experimental communications. A common example of LF data transmission is the "RF Controlled Atomic Clock" on your desk. It receives the LF data stream from WWVB (for us folks in the U.S.) and gathers the neccessary info to set your clock.
:)
And the noise issue is a rather large one, which LF transmission are particularly prone to, much like the audio band (20-20kHz), and from some of the same sources (lightning strikes, natural radio, etc).
I think the biggest problem is with environmental and ecological concerns. As far as gee-whiz factors are concerned, it is kind of neat, but aside from that, the impact on species exposed to it is by far a more important issue than whether or not submariners should get thier e-mail. Submarines are one of those places where maybe people just shouldn't have net access... but then again, I feel that way about most politicians too.
umm, that is not neccessarily true. a lot of early wireless lan products, and quite a few on the market today, are _not_ encrypted. the newer, forward thinking products, fortunately, are.
you'd be amazed at how insecure wireless data systems actually are. when you are reading the specification for something and you run across the statement "the technical knowledge and equipment neccessary to intercept and decode this system is out of reach of the average person, making this an extremely secure system" it makes you scratch your head. this was [paraphrased] from the mobitex specification, which requires a handful of parts from radio shack and a bit of software.
be wary of _any_ wireless data product that does not implicity state it uses encryption, and states what the encryption algorithm is. a lot of protocols use something called 'bit scrambling' to maintain data integrity, and the marketing types always confuse this with encryption.
basically, they will need to do a lot with ensuring compliance of the electrical wiring in homes to minimize interference with licensed users of radio spectrum. i routinely find spurious emmisions from all kinds of household devices (including home networking stuff) all over the shortwave band, and occasionally up into the vhf band as well.
do you think the 'main-streaming' of political activism, combined with the splintering of historically 'left-wing' ideologies has caused credibility to be lost for activism in general? do you think that the ease of access and publication on the internet has lent itself to this loss of credibility, if it exists at all? it seems that the media, at least in certain markets, has turned a deaf or apathetic ear towards any type of political activism that is not clearly mainstream. do you think the internet, and activism in general, can turn this around?
thanks.
it actually has not declined as much as one would think. and would you really want to take away the spectrum used for experimentation? the same experimentation that has led to some of the wireless technologies you take for granted? it has much in common with the open-source movement, and in the grand scheme of things, amatuers have _very little_ spectrum allocated to them. if you want spectrum for ip, go after the allocations held (and underutilized) by the railroad industry and the military.
:)
amateur radio still has it's benefits and is still a much valued service/endeavor. after all, what is more fun than converting an old radar detector into a 10Ghz 25mW fm transceiver?
considering that the rim950 with service from bell south doesn't use any encryption, it doesn't really matter now, does it?
:)
seriously, i figured they would be using encryption but running a dsp and decoding it as plain old mobitex works fine. granted, you get all the other crud on the mobitex network but if you filter for the man # you want it shouldn't be an issue.
and they said the same thing about mdt's. rember, bit scrambling is _not_ encryption, it's a data integrity mechanism...
The service is generally provided via MOBITEX by Bell South Wireless Data and a few other providers. I like my RIM pager, and it doesn't "redirect" e-mail like someone mentioned (might have been the way they were set up). The only major problem with RIM pagers is they are NOT SECURE. You can decode the messages rather easily off-the-air.
i am actually suprised this wasn't done earlier with amateur satellites, as it is (aside from the issues involving communication with orbiting communications systems) just a wireless network connect. if the satellite was in polar orbit you'd have availability problems, but a sat in the clarke belt would be nifty.
anyone know of plans in the amateur community to do this?
oh, and check out AmSat for info on amateur satellites and whatnot.
i currently get my network connections using freewave
.02.
data tranceivers. they are NOT cheap, and are only 115kBps, but they will go up to 30+ miles line of
site with external high-gain antennas. these are the same tranceivers used in various remote data acquisition applications. the advantage being they act as modems, and can emulate a hayes modem making them
usable in many applications. my current link is runnin 100mW to 10dB yagis.
the problem with external antennas on wireless ethernet devices is the FCC requires you to purchase the antenna from the same vendor as the actual tranceiver in order to maintain compliance with part 15 rules. purchasing a seperate antenna is totally doable, but if you cause _any_ interference and the system is deemed to not be in compliance with part 15 rules, you face fines and confiscation of equipment.
just my
personally, i think a more pure approach to zen is more appropriate and can be applied to anything, not just code. people who are interested should check out 'zen mind, beginner's mind' by shunryu suzuki (isbn 0-8348-0052-7) of the soto school. he is the founder of zen temple san francisco. very good, and for me, invaluable.
Well, I think that her discovery was simply a different approach. This happens ALL THE TIME in scientific research. Sometimes you can't see the forest from the trees when you are buried. It sometimes takes someone without any experience to try something no one else has even considered. So I will give her the benefit of the doubt, for the time being.
After all, the CRC tables [Chemical Rubber Corp book of tables] had to be recalculated in the seventies when a 14 year old discovered they were all wrong.