#195796 - 02/13/10 12:16 AM
Re: When 911 fails
[Re: buckeye]
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Addict
Registered: 09/19/05
Posts: 639
Loc: San Francisco Bay Area
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So, like any piece of our equipment, be sure to test it before you need it. Excellent advice I've learned several times, and I'm sure I'll learn it again. :-> We had a power outtage some time ago, and I learned that all my stuff works on my UPS, but it sucks power like a pig. I'll turn off my desktop and monitor and switch off the WiFi unit, plug the little EEE PC into the ethernet port on the modem and use that for any internet access I can get.
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#195806 - 02/13/10 03:02 AM
Re: When 911 fails
[Re: buckeye]
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Geezer
Registered: 01/21/04
Posts: 5163
Loc: W. WA
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Buckeye, thank you for the additional information.
When I talk about communication failures, I am almost always not referring to hams, simply because they all seem to be more resourceful than most people, disaster or not. Before sat phones, they were often the ONLY communications available for the first few days of any disaster.
My repeater question was due to my ham father's problems when he lived in Las Vegas, which is in a bowl surrounded by mountains. The repeaters were up on the mountains, and he said without them, a ham would need a much taller antenna than he had to get out of the valley.
I've never seen a ham repeater tower, so I was wondering if they are very susceptible to earthquakes? By your post, I am assuming that if they did fall over, some hams could put them back up, or do what needed to be done.
One advantage of hams relaying messages is that one operator in a disaster area can pass messages to other hams more or less in line-of-sight, to others who are in a less damaged area, until the messages reach a ham in an area can then make a regular phone call to the intended receiving party.
If Philip, for example, was in SF during a major quake and could get to a ham, a message might be relayed north or south (probably not east) to one who had an operating phone line, and that person could call Philip's relatives in Colorado Springs.
Hooray for hams! No one thinks of them except if they interfere with someone's TV, until a disaster strikes. Then they tend to be quite popular!
Sue
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#195814 - 02/13/10 04:12 AM
Re: When 911 fails
[Re: CANOEDOGS]
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life is about the journey
Member
Registered: 06/03/05
Posts: 153
Loc: Ohio
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i read someplace that a Slinky pulled out to it's max size could be used! Yep, most any type of metal wire will work. However, it works (propagates) better when it is roughly a multiple (such as 1/4 or perhaps 1/3) the length of the wavelength you are transmitting on. Distance above and relative to ground (and several other factors) are key variables also. Reception across a much wider range can be achieved by a much more generic antenna. Follow some of the ham groups and you'll find there are people who spend a good deal of their time modeling expected antenna performance and have discussion on difference of opinions about antenna design and performance as heated as anything else.
_________________________
Education is the best provision for old age. ~Aristotle
I have no interest in or affiliation to any of the products or services I may mention. Should I ever, I will clearly state so.
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#195823 - 02/13/10 02:50 PM
Re: When 911 fails
[Re: buckeye]
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Old Hand
Registered: 10/10/01
Posts: 966
Loc: Seattle, WA
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One unexpected problem I ran into last weekend: I recently purchased a small back-up UPS for my Cable Modem and Router. When I went to test it, my interal home router ran fine but the Cable modem won't run off of the back-up. Talked to the cable company and it seems the frequency generated by the battery back-up may be outside the tolerance (to far outside of 60Hz) the cable modem wants to see. (I probably didn't say that technically correct, but in short, they don't work together). I've read that more expensive units may do a better job and I believe a few even come with guarantees.
So, like any piece of our equipment, be sure to test it before you need it.
Yah, a lot of lower quality UPSes don't provide clean power. Another gotcha with UPSes is that a number of them will not allow you to turn the UPS back on after you turn them off. This can be problematic if you are trying to conserve your power. Also, make sure your unit has the ability to silence the power outage alarm. Of course, you can open the unit and physically disconnected if you are comfortable doing that. -john
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#195826 - 02/13/10 05:44 PM
Re: When 911 fails
[Re: CANOEDOGS]
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Geezer
Registered: 01/21/04
Posts: 5163
Loc: W. WA
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Wouldn't your slinky have to be vertical for this use? Need a skyhook to hold it in place... Or a helium balloon.
Sue
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#195836 - 02/13/10 09:01 PM
Re: When 911 fails
[Re: Susan]
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Addict
Registered: 09/19/05
Posts: 639
Loc: San Francisco Bay Area
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> I've never seen a ham repeater tower Lots of photos here from one repeater group: http://www.carlaradio.net/community/pictures/gallery/Two example photos (not necessarily typical :->) > one operator in a disaster area can pass messages to other hams more or less > in line-of-sight That's true with VHF/UHF frequencies; that's what the repeaters are for - to increase the line of site. But with HF frequencies, you've got truly worldwide communications from your station if you have a good antenna. We've got a portable antenna that mounts on our van, and from the San Francisco Bay Area, we get all the way to the east coast without repeaters - and with a not good antenna. Here's a photo of it on our van in Death Valley: As you can see we're surrounded by mountains, but we had chats with a guy in Berkeley and one in Santa Cruz. In an emergency, I would expect to be able to reach other hams outside California without having to rely on repeaters or other hams in line of sight to get our messages out of the zone of damage. We regularly check in to a net in Reno from our house, the other side of the Sierras. HF is great stuff, and I recommend that people get their general license (minimum license required for HF), an HF transceiver, and practice using it.
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#195837 - 02/13/10 09:29 PM
Re: When 911 fails
[Re: philip]
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Geezer
Registered: 01/21/04
Posts: 5163
Loc: W. WA
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Thanks for that info! I guess amateur radio electronics have improved considerably since the last contact I had with it in 1986!
That's really nice to know. I didn't realize you could pick up east coast signals with just a vehicle antenna. WOW!
Sue
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