Recommend a B.O.B. Walkie-Talkie

CroMAGnet

Flashlight Enthusiast
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Los Gatos, CA
Just looking for a walkie talkie type of hand held two way radio system for two that can traverse 30-50 miles for emergency use. Good for our BOBs. Compact, portable and reliable and uses common batteries for decent runtime.

Anyone?
 
No such animal! I'm serious. 30-50 miles is a problem - too far for an HT unless you are using a repeater, with 2 small posiblities that MIGHT work

1)6m/10m Ham band HTs - rare as hens teeth - 6m low power is available, but....
2)11m "CB" HTs MIGHT work if you can get groundwave working for you, but that's luck at that freq

Believe it or not, even with "bigger" gear 30-50 miles is a problem. 6m High power radios at a good height will work. 20m/40m rigs will work _IF_ you setup an NVIS type antenna system

IF you are willing to use repeaters, 2m and 70cm ham band HTs and mobiles will work, but then you are relying on "fixed" infrastructure (the reason they work is they have antennas at VERY high points - mountain tops, skyscrapers etc

Best bet without repeaters would be a "Mobile" (aka vehicle mounted) 6m rig at fairly high power 50-100 watts
 
There is no easy answer for how far. It depends on the frequency, the power, the antenna, and the terrain.
FRS radios are good for maybe 1/2 mile in open space without a lot of trees but there are instances of over 20 mile transmission on a hill across a lake.

Where will you be using it?
How much can you afford?
How long will you be using it?
Do you want to be or have to be legal?
 
It sounds like you want a way to contact family members (who might be in another part of town) in the event of an earthquake or something.

There is no such thing as a handheld voice radio system that can /reliably/ reach more than a few miles except direct line of sight. HF systems can reach that far but only randomly, depending on weather conditions, sunspots, motion of the ionosphere, etc. You get a tremendous range improvement with a ground plane, e.g. a magnetic roof mount antenna that you plop on top of your car. So for a car BOB, you should certainly include a roof antenna. What you really want, though, is a repeater on a mountaintop that has backup power and all that.

If you're into this sort of thing, I'd say get ham licenses, join a radio club with such a repeater (so you can help with its upkeep), and get the appropriate radios (normally these will be 2 meter or 440 mhz HT's, that are basically as small as cell phones).

If you don't want to mess with this, I'd say just get decent FRS/GMRS radios and figure they're just for short range use. They can reach a few blocks in a city, or somewhat further in more open terrain.

Note also that in disasters, communications systems are generally overloaded with actual emergency traffic (where someone is going to die if a message doesn't get through) and it's inappropriate to increase the load with lower priority stuff (e.g. messages simply asking or saying where somebody is and whether they are ok).

For reasons I don't understand, there's not much movement towards spread spectrum portable text-only radios, which use much less bandwidth than voice radios and so can handle far more traffic and have greater range for a given amount of transmit power. It would be pretty straightforward to make a portable radio that could send text for hundreds of miles albeit very slowly (several minutes for a 100 character message). That would be good enough for many emergency purposes.
 
You got it right Paul. Find each other in an earthquake type emergency. I thought I saw some toys at Target that had better range than the ones mentioned and I also thought that the technology had advance a lot more than it has.

I was thinking like a couple of handeld CB radios or something along those lines. Pick something like channel 93 and you'd probably be alone.

So just for maybe an hour of runtime at least with at least a mile range. We don't typically have buildings taller than 3 stories around here. And it's usually sunny /ubbthreads/images/graemlins/smile.gif

Thanks again for the good details to catch me up a bit on the topic /ubbthreads/images/graemlins/grin.gif
 
GMRS radios say "range up to 5 miles" on the package. Maybe that's what you saw. It means in ideal conditions. Reliably and when there's no interference, it's realistically more like 1/4 or 1/2 mile. Keep in mind that in an emergency, the channels will all be jammed. It's best to stay off the radio unless you have your own emergency, e.g. you're trapped in a burning car or something.

As for finding each other after an earthquake, better to just select a meeting place ahead of time and try to make your way there, than depend on radios. For example, some open area near your home.

The equipped.org forums might be a better place to discuss this kind of question.
 
Old-tech CB radios could do the trick. Around here pretty much all 40 channels are dead air, so I can use mine to contact friends and not worry about interference. The range of vehicle models is ridiculously longer than handhelds but I have a pretty standard handheld that works great. Mine is a Cobra 37ST, I got it on sale for $90 Canadian I think. It came with an antenna obviously, but it is the screw-on BNC type. I bought an extended range antenna from Cobra for something like $12 and it doubles the range of the unit to about 2-4 miles depending on conditions, and it screws on the same way as the one that came with it. CB radios are more prone to interference, but you can also tinker with the squelch way more to pick up weak transmissions.

GMRS (forget FRS their transmitters are capped at .5W) are much clearer when you transmit because of FM band, but their range on civilian models is capped. In Canada you don't need a licence for GMRS operation, but last I heard you still need one in the US. In Canada the GMRS transmitters are capped at 2W, but in the US I believe it is 5W. Anyways, as previously mentioned, the range under realistic and practical conditions is about 1/2 mile in urban areas, although you will get way better than that in open rural areas. The best GMRS radios I've personally used (I sort of collect them /ubbthreads/images/graemlins/wink.gif ) are made by Uniden, I have the Uniden GMR885 pair seen here. They have huge easy to read displays, and excellent transmission clarity. You can also get NOAA weather reports (updated hourly) on them and they can be set to "disaster mode" where the NOAA channel is checked every 5 seconds for an emergency broadcast. If you're using the radio, it just sounds like a momentary pause. There's also a power boost key that uses the full power (2W on this model) for the transmitter. This helps save battery power since most transmissions will work with 1W which is the default when you transmit. Transmissions are changed to .5W if you're on an FRS-only channel.

Anyways, that's what I'd recommend for a GMRS set. Most Motorolas are garbage either because they have no features, or because Motorola uses Ni-Cd battery packs in their rechargable sets for some reason. These Unidens are cheaper than the higher end Motorola set (T7100), have more features, and are smaller!

CB might be a good way to go however, as you could certainly get better range out of them, especially on the car-mounted units. I've heard stuff about 10 miles away in my car, while the farthest I've heard on GMRS was 3 blocks in the city. CB gear is more expensive though, a basic model here is about $80 Canadian, I sprung for a more expensive model ($110, also on sale) which featured a scan feature and I'm quite pleased with it. CB is mostly discarded now because it's so old, but if everyone in your area is on GMRS...you won't have to deal with clogged channels! Oh yes, CB no longer requires a licence in Canada, I believe it's the same in the US. Most sets do not include an antenna however, so you're looking at another $50 (what I payed in Canadian $$) to get a pretty good antenna from RadioShack. I also had to calibrate the antenna myself with an SWR/Field Strength meter, also from RadioShack. Now that that's out of the way though, I'm pretty much set for good. Definitely more expensive, but for the added range and abilities...I'm one guy who thought it was worth it.
 
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paulr said:If you're into this sort of thing, I'd say get ham licenses, join a radio club with such a repeater (so you can help with its upkeep), and get the appropriate radios (normally these will be 2 meter or 440 mhz HT's, that are basically as small as cell phones).


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I agree with this as the best advise in this thread, but only to a point. The problem with UHF/VHF repeaters is that if TSHTF, the repeaters probably won't work either, since they rely on commercial power like most forms of communication. CB wont work out of line of sight either, except during the random "skip" propagations, and with the variable of sunspot cycles, you are rollng the dice. 2M simplex relays are a possibility, but not something I'd expect in an emergency situation.

That said, my advice is to get a HAM license, get HF priviledges and use the low bands of 40 and 80 meters.

Myself, I have an extra class HAM license, and can send morse code at 18 words per minute (not great, but adequate) so I can communicate pretty much anywhere in the world under pretty much any conditions. This may or may not be the solution for you.
 
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Malpaso said:
...snip...

The problem with UHF/VHF repeaters is that if TSHTF, the repeaters probably won't work either, since they rely on commercial power like most forms of communication

....snip...

That said, my advice is to get a HAM license, get HF priviledges and use the low bands of 40 and 80 meters.

Myself, I have an extra class HAM license, ...snip...

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I don't know about near you, but around here I know of at LEAST 6-7 repeaters with WIDE area coverage that either have 72+ hrs of batteries, or are on MAJOR league backup gen sets - as in hospitals etc. Of course t least 3 of those _WILL_ be tied up with local Em-comm traffic (NYC, Nassau, and a NYC/Nassau General Info link - NOT emcomm, but will be helping the Emcomm folks)

As you say - 40-50 miles is HARD - you will almost HAVE to use 40m or 80m with a NVIS type antenna (Near vertical Incidence Skywave)

I too am an Extra, but an "Extra lite" who really needs to spend a lot more time on my code

I'll agree - want real comms? Get a Ham ticket. I know the original poster was from CA - not sure what part - I know the LA area has some super repeaters with gen sets that have range to go 100+ miles (Mountains are a good thing)

73 de KG2V
Queens County Emergency Co-ordinator
NYC District ARES
 
Then there's the infamous 675 repeater by Rockafeller Center, plagued by the idiot who runs it along with jammers
 
Yeah, there are idiots - like the jammer that plagues on of the nets I'm on, but in general there are enough repeaters around - I tend to hang on 147.00 or the HoSARC box, but scan the WB2ZSE UHF, N2ROW, the two K2CJP boxes, and the LIMARC "85" machines
 
I have used a 75 watt linear amp on a CB car radio to talk 45 miles to a base station once, but for practical purposes you are lucky to get 10 miles from mobile to mobile using standard 4 watt radios. With base stations you can get 50 miles conditions permitting without a beam antenna.
 
There are lots of repeaters in every urban area. VHF does inherently carry a little further than UHF and have better penetration of buildings, due to physics. But there's not as many VHF frequencies available, so there's more contention, interference, etc.
 
In urban areas there's a mix of open and closed repeaters. Most are operated by clubs with open membership. If you become a regular on some repeater, it's generally friendly to join the club that operates it, so you can contribute to its upkeep either financially or with volunteer work. Anyway, in an emergency, any repeaters that are able to keep operating (including closed ones) will do their part.

VHF gets through and around obstacles better than UHF does, because of its longer wavelength. UHF is basically line of sight.
 
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