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#1
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I oversee an ARES group.
We would like to provide digital still photos back to the Emergency Management Offices from disaster sites. What type of gear would I need to do this ? How long does it take to transfer a photo ? Thanks, Steve N2UBP |
#2
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"Steve Stone" wrote in message
... I oversee an ARES group. We would like to provide digital still photos back to the Emergency Management Offices from disaster sites. What type of gear would I need to do this ? How long does it take to transfer a photo ? We send photos across our network now and again. Also drawings, power point presentations, spread sheets, software, whatever. Network is 9600 baud, about three dozen nodes. Takes anything from a minute to several hours. Depends on the size of the photo file. If you really need high resolution 1.5 MB JPEG that takes awhile ;-) Usual case is in the several minutes range. We use various windows applications. You could just as well use Linux or MAC, all work fine. Email is simplest since the recipient can do whatever they want with the attachment, and the email can explain why the picture was sent, when and where it was taken, etc.. -- ... Hank http://horedson.home.att.net http://w0rli.home.att.net |
#3
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![]() "Steve Stone" wrote in message ... I oversee an ARES group. We would like to provide digital still photos back to the Emergency Management Offices from disaster sites. What type of gear would I need to do this ? How long does it take to transfer a photo ? Thanks, Steve N2UBP Use whatever packet system/protocol you have. The time taken to send a binary file such as a jpg photo is simply a function of the speed of the network and the size of the file. There is no "magic" to it at all. You might want to take a look at Slow Scan TV. It is potentially faster than packet but does require some specialized equipment. 73 Roger ZR3RC |
#4
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"Roger Conroy" wrote in message
... You might want to take a look at Slow Scan TV. It is potentially faster than packet but does require some specialized equipment. All it takes these days is a laptop with a soundcard and a cable with a couple of resistors in it. Not all that specialized. Well, OK, if you want to do it right you need another cable with a transistor and a resistor. If you would prefer a pretty box to something homebrew you could go out and buy a RigBlaster or something along those lines. Works just as well on VHF as HF. There are plenty of RigBlaster clones out there, and some of them cost less than you pay for the box. I tend to wince a little at getting a commercial interface because I'm inclined to prefer melting solder, and it's terribly simple. But these interfaces are awfully cheap, and having it all in a neat little box is probably worth it. Most of the common software includes the wiring diagrams in the help files, and they pretty much all show the same circuit. The only thing the least little bit tricky, and the commercial boxes won't help you with this, is setting the input level. You need resistors or a pot between the laptop and the mike input of your radio. The level needed varies A LOT from rig to rig, and you need to get the level down to where the rig won't distort the audio. This will take some tinkering. With FM, a deviation meter might be handy to do this, but you can probably get close by having someone listen to your audio. A lot of repeaters will report your deviation given some touch tone beeps. Don't be thinking more audio is better - it's decidedly worse. This is probably even more true on FM than on SSB. All you need is enough to be clear on the other end. Take a peek at MMSSTV, which is probably the most popular SSTV program and it's free. MixW is another popular one ... it's shareware, and it's not as good for SSTV as MMSSTV, but it does about every mode known to man, so it does give you a chance to experiment a bit. I think you can use it for some period of time before it starts nagging you to pay, so you can get a feel for whether it's worth it. ... |
#5
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"Roger Conroy" wrote in message
... You might want to take a look at Slow Scan TV. It is potentially faster than packet but does require some specialized equipment. All it takes these days is a laptop with a soundcard and a cable with a couple of resistors in it. Not all that specialized. Well, OK, if you want to do it right you need another cable with a transistor and a resistor. If you would prefer a pretty box to something homebrew you could go out and buy a RigBlaster or something along those lines. Works just as well on VHF as HF. There are plenty of RigBlaster clones out there, and some of them cost less than you pay for the box. I tend to wince a little at getting a commercial interface because I'm inclined to prefer melting solder, and it's terribly simple. But these interfaces are awfully cheap, and having it all in a neat little box is probably worth it. Most of the common software includes the wiring diagrams in the help files, and they pretty much all show the same circuit. The only thing the least little bit tricky, and the commercial boxes won't help you with this, is setting the input level. You need resistors or a pot between the laptop and the mike input of your radio. The level needed varies A LOT from rig to rig, and you need to get the level down to where the rig won't distort the audio. This will take some tinkering. With FM, a deviation meter might be handy to do this, but you can probably get close by having someone listen to your audio. A lot of repeaters will report your deviation given some touch tone beeps. Don't be thinking more audio is better - it's decidedly worse. This is probably even more true on FM than on SSB. All you need is enough to be clear on the other end. Take a peek at MMSSTV, which is probably the most popular SSTV program and it's free. MixW is another popular one ... it's shareware, and it's not as good for SSTV as MMSSTV, but it does about every mode known to man, so it does give you a chance to experiment a bit. I think you can use it for some period of time before it starts nagging you to pay, so you can get a feel for whether it's worth it. ... |
#6
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"Steve Stone" wrote in message
... I oversee an ARES group. We would like to provide digital still photos back to the Emergency Management Offices from disaster sites. What type of gear would I need to do this ? How long does it take to transfer a photo ? We send photos across our network now and again. Also drawings, power point presentations, spread sheets, software, whatever. Network is 9600 baud, about three dozen nodes. Takes anything from a minute to several hours. Depends on the size of the photo file. If you really need high resolution 1.5 MB JPEG that takes awhile ;-) Usual case is in the several minutes range. We use various windows applications. You could just as well use Linux or MAC, all work fine. Email is simplest since the recipient can do whatever they want with the attachment, and the email can explain why the picture was sent, when and where it was taken, etc.. -- ... Hank http://horedson.home.att.net http://w0rli.home.att.net |
#7
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![]() "Steve Stone" wrote in message ... I oversee an ARES group. We would like to provide digital still photos back to the Emergency Management Offices from disaster sites. What type of gear would I need to do this ? How long does it take to transfer a photo ? Thanks, Steve N2UBP Use whatever packet system/protocol you have. The time taken to send a binary file such as a jpg photo is simply a function of the speed of the network and the size of the file. There is no "magic" to it at all. You might want to take a look at Slow Scan TV. It is potentially faster than packet but does require some specialized equipment. 73 Roger ZR3RC |
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