Posted: 5/2/2013 9:51:03 AM EDT
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I realize there is a whole Ham Radio forum, but this question specifically related to a SHTF/EOTWAKI scenario.
Imagine EMP or Katrina class hurricane with widespread power outage. Do repeaters require electricity to operate? If so, what's the merit to having access to (and license/knowledge to operate) a Ham radio if the power is out/grid is down? Would a ham radio be limited to simplex operation in that situation? Thanks. |
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Quoted:
I realize there is a whole Ham Radio forum, but this question specifically related to a SHTF/EOTWAKI scenario. Imagine EMP or Katrina class hurricane with widespread power outage. Do repeaters require electricity to operate? If so, what's the merit to having access to (and license/knowledge to operate) a Ham radio if the power is out/grid is down? Would a ham radio be limited to simplex operation in that situation? Thanks. Repeaters do require electricity for all the electronics in them to keep their wheels turning. Some of them have backup power. Solar panels, wind generators and batteries come to mind. If the regular repeaters are no longer in service, you could always turn on your own if you have one available, or if not use simplex. The benefit to accessing a repeater is to have commo w/ others. |
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Most amateur radio operators have access to the lower frequencies call bands. These lower frequencies are useful for worldwide communication, usually with higher power. But even the higher frequency bands like 2 meters at 144 mhz is usefull for communication without using a repeater. But you would need a good antenna and some hight above ground. The range is variable. A hand held 2 meter rig can be used for comms up to 50 miles if you are 100 feet or more above the ground with a clear view to the horizon. Ive done this many times. If you are between buildings in a city, maybe less than 1 mile. Ive used 2 meter handy talkies during a heat inversion for a round table conversation between 6 states using 5 watts on my back deck. The conditions are extremely important. With that said, I wouldnt rely on the VHf bands like 2 meters. I would use 20, 40, 80 meter bands only for worldwide comms. A 50 watt radio and a foor antenna will get you around the world. I use a very inexpensive antenna on 20 meters called a quad loop at 60 feet. If I can hear a station, they can hear me. It works much better than any dipole and is almost as good as a 3 element beam but not quite. Thats about all I can cram into this nutshell right now. |
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Don't need a repeater to talk worldwide on HF frequencies. Repeaters are good for local low powered comm. Think handheld radios.
Repeaters go down, there are countless other options. Repeaters are but one pebble in the gravel pit.  But most repeaters do have standby power.
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Hams tend to pride themselves on being self-reliant, and that attitude tends to be reflected in the repeaters they install: Backup power is very common on these repeaters.
Typically, this takes the form of solar panels connected to rechargeable batteries, or a generator. Some ham repeaters are located next to commercial or government radio facilities, and thus have access to whatever backup power is available for these other services. |
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Quoted:
Hams tend to pride themselves on being self-reliant, and that attitude tends to be reflected in the repeaters they install: Backup power is very common on these repeaters. Typically, this takes the form of solar panels connected to rechargeable batteries, or a generator. Some ham repeaters are located next to commercial or government radio facilities, and thus have access to whatever backup power is available for these other services. +1 Most of our repeaters have battery/ generator back up good for a couple weeks. There are also several linked repeater systems that allow you to talk 100s of miles on just 2m FM. |
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Since you are worried about EMP, I will make the assumption that the repeater antenna high in the air will be fried by the pulse, as well as the co-ax and repeater itself. To be blunt, all the back-up power in the world won't help a fried antenna and repeater. And the nuclear radiation that follows the second volley of missiles following the first EMP nuke. 
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Quoted:
I realize there is a whole Ham Radio forum, but this question specifically related to a SHTF/EOTWAKI scenario. Imagine EMP or Katrina class hurricane with widespread power outage. Do repeaters require electricity to operate? If so, what's the merit to having access to (and license/knowledge to operate) a Ham radio if the power is out/grid is down? Would a ham radio be limited to simplex operation in that situation? Thanks. They need electricity but a decent rig can still run on a car battery alone. Add a generator and you have radio for as long as you keep the genny running. FerFAL |
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Since you are worried about EMP, I will make the assumption that the repeater antenna high in the air will be fried by the pulse, as well as the co-ax and repeater itself. To be blunt, all the back-up power in the world won't help a fried antenna and repeater. There are commercial off the shelf products to protect repeater components from lightning and EMP. I suspect the better-constructed repeaters would survive an EMP event, seeing as they deal with lightning strikes on a fairly routine basis. Electromagnetic Pulse and the Radio Amateur - Part 1 Electromagnetic Pulse and the Radio Amateur - Part 2 Electromagnetic Pulse and the Radio Amateur - Part 3 Electromagnetic Pulse and the Radio Amateur - Part 4 |
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Since you are worried about EMP, I will make the assumption that the repeater antenna high in the air will be fried by the pulse, as well as the co-ax and repeater itself. To be blunt, all the back-up power in the world won't help a fried antenna and repeater. There are commercial off the shelf products to protect repeater components from lightning and EMP. I suspect the better-constructed repeaters would survive an EMP event, seeing as they deal with lightning strikes on a fairly routine basis. Electromagnetic Pulse and the Radio Amateur - Part 1 Electromagnetic Pulse and the Radio Amateur - Part 2 Electromagnetic Pulse and the Radio Amateur - Part 3 Electromagnetic Pulse and the Radio Amateur - Part 4 Thank you for the education, I will have to read up on that. |
| My command has a ham club and we run a 1.25 meter repeater that covers the valley from end-to-end. The command is rather serious about electrical power and has a 1 MW generator backed by a 640 KW one. There's a double lined underground tank good for a week and they have an agreement with the base to take fuel from their huge above ground tanks. There are two 250 KW UPS systems too. The repeater is plugged into both technical and critical power and will very more than likely survive anything. |
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Yes, they require power. We have battery backup and generators. If that's not possible (e.g. tornado hits the repeater) then we have a simplex message trafficking plan, with a member with a good multi-band rig going to one of the higher hills in town to establish a message station. Should be able to operate on 2m and 440 simplex in town via handhelds, and mobile radios through most of the county. And then there's HF. |
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Since you are worried about EMP, I will make the assumption that the repeater antenna high in the air will be fried by the pulse, as well as the co-ax and repeater itself. To be blunt, all the back-up power in the world won't help a fried antenna and repeater. There are commercial off the shelf products to protect repeater components from lightning and EMP. I suspect the better-constructed repeaters would survive an EMP event, seeing as they deal with lightning strikes on a fairly routine basis. Electromagnetic Pulse and the Radio Amateur - Part 1 Electromagnetic Pulse and the Radio Amateur - Part 2 Electromagnetic Pulse and the Radio Amateur - Part 3 Electromagnetic Pulse and the Radio Amateur - Part 4 Actually the use of cavity filters on repeaters provides lots of protection. if the reciever is protected from a 100 watt transmitter 600 kHz away on the same transmission line, it's not going to notice EMP. Plus I've seen some hams running EMP grade Polyphaser protectors (~$100). |
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Since you are worried about EMP, I will make the assumption that the repeater antenna high in the air will be fried by the pulse, as well as the co-ax and repeater itself. To be blunt, all the back-up power in the world won't help a fried antenna and repeater. Hard to "fry" a wire di pole... It's Just wire..... |
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Quoted:
Since you are worried about EMP, I will make the assumption that the repeater antenna high in the air will be fried by the pulse, as well as the co-ax and repeater itself. To be blunt, all the back-up power in the world won't help a fried antenna and repeater. Hard to "fry" a wire di pole... It's Just wire..... it wouldnt "fry the wire" the antenna would concentrate the electrical pulse then feed it down to the radio, frying the radio. removing the antenna feed wire from the radio would protect the radio so there would be no damage to the radio. |
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it wouldnt "fry the wire" the antenna would concentrate the electrical pulse then feed it down to the radio, frying the radio. removing the antenna feed wire from the radio would protect the radio so there would be no damage to the radio. this is SOP around here, best lightning protection I can afford 
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