CHAT Need a Good Two-Way Radio

Tundra Gypsy

Veteran Member
With things getting a little weird; I need to stay in touch with my neighbor who lives a few miles from me. If power is out and all cell phone towers are down, I need to be able to communicate with him. There are so many radios on Amazon that I have no idea which one would be the best. I don't want to get an expensive one; any ideas? Thanks so much. I need to get the radios a.s.a.p..
 

Knighttemplar

Veteran Member
Much depends on terrain. Is the neighbor line of sight from your place? Will either of you be inside buildings or cars? CB might work with a good outside antenna or FRS/MURS. If you both can get novice licenses then 2 meter radios would work but you need line of sight. How will you power them?
 

Raffy

Senior Member
Not sure where you are located, but there are several options:

1.) You and your neighbor each get Technician Class amateur radio licenses. Yes, a little work is involved but you will be able to use the 2-meter ham band and use repeaters to communicate if you can't by line of sight transmission. Repeaters are usually mounted on hills or high towers to retransmit signals over a much larger area. You can also use the 10 meter ham band on voice frequencies between 28.3 and 28.5 MHz (or thereabouts), but of course you'll need a different radio than you would use for 2 meters, in most cases. IMO, this is the best option because it is the most versatile.

Most amateur repeaters have some form of emergency backup power, so they should be available for use for quite a while after cell towers and other systems go down.

2.) CB radio is another option. This might be the most viable for you. CB's can be had for about $100 brand new, not including power supply and antenna. These operate close to the 10 meter ham band. No license required. If you get what is called single sideband (SSB), you can get a range of 25 miles or more line of sight distance. Since CB frequencies are lower, their groundwaves travel for longer distances than the higher frequency options do. Of course, SSB CB transceivers are more expensive (about $200 or so).

3.) FRS, GMRS (Family Radio Service, General Mobile Radio Service). These can be had for quite cheap (as low as $50 or so for a pair of radios), but they don't have much range. Don't expect more than 1 to 2 miles of range, realistically, in most cases, unless one of you is atop a hill.
 

Thinwater

Firearms Manufacturer
If you go the CB method, a good base station antenna is needed. See link for my CB and 10 meter HAM radio. It will give you many times the distance of a vehicle mounted antenna. Mounting it on a 20 foot pipe or pole makes it even better. With just a pipe for a tower, you can lift it and drop it into a hole with the antenna on top by yourself. It is around $100. For $50 you can still get a good one.

Good coax to hook the antenna to the radio also helps, a lot. You can lose 70% of your power, both send and receive using crappy coax. At a minimum, use the RG8 foam filled but LMR 400 is WAY better. This cable and base antenna will give a CB MANY miles of range plus allow you to listen to skip from around the country, especially if you go with a CB with side band coverage.

 

Publius

TB Fanatic
Many here made some good suggestions and looking around for mobile CB radios and try looking around for truck stops as many sell these along with mobile unit antennas that can easily be adapted to home use.
Now these mobile CB radios require and transformer to step down 120Vac to12Vdc for in home use and or can be run off a 12V car battery. with a battery charger to keep the battery charged it will run for quite a while off a car battery and you have a range of 20 miles easy with the four watt output these have.
 
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Raffy

Senior Member
If you go the CB method, a good base station antenna is needed. See link for my CB and 10 meter HAM radio. It will give you many times the distance of a vehicle mounted antenna. Mounting it on a 20 foot pipe or pole makes it even better. With just a pipe for a tower, you can lift it and drop it into a hole with the antenna on top by yourself. It is around $100. For $50 you can still get a good one.

Good coax to hook the antenna to the radio also helps, a lot. You can lose 70% of your power, both send and receive using crappy coax. At a minimum, use the RG8 foam filled but LMR 400 is WAY better. This cable and base antenna will give a CB MANY miles of range plus allow you to listen to skip from around the country, especially if you go with a CB with side band coverage.

Great advice here! LMR-400 is great coax and has much lower loss than most others, although it can be expensive. I use it for higher VHF and UHF frequencies where its lower loss really makes a big difference. For CB frequencies, RG-8X will work sufficiently well enough as long as you keep the length of the coax at 100 ft or less. But if you can afford LMR-400, by all means, go for it!

Definitely get a good base antenna, though, and make sure your neighbor has a similar antenna on his end. It's important that both his and yours be vertical. If yours is vertical and his is horizontal, there will be a huge loss of signal between you two. So both of you need to have both antennas vertical or both horizontal. Vertical is a bit more practical, so I would recommend that.
 

LoupGarou

Ancient Fuzzball
While Potato Country is a rather large (and vague) area, knowing a bit more closely about the conditions around and more importantly, BETWEEN the two (or more) houses that you want to communicate with is the main factor... And this goes for ANYONE wanting to communicate with the other locals in your group.

Ask yourself these questions:
  1. Can I physically see (with your eyes, binoculars, or a telescope) the other locations from my house (even if this is only when standing on your roof)?
  2. Can I guarantee that there is only trees and other houses between my house and the other houses?
  3. Do I know for a fact that there is actual Earth between me and the other houses?
The Earth is NOT Flat, nor is it perfectly round. It's rather lumpy, even on the supposedly flatter or rounder parts. Even the ocean gets an attitude and stays rough. That being the case, and added to the fact that everything that is matter works against a RF signal going from one point to another (including atmospheric air), anything between you and the other houses is going to attenuate (reduce) the signal. If you reduce it too much, then you won't have enough signal level at the far end to make the connection reliable. And adding to that fact, the issue that different frequencies are attenuated by different matter, at different amounts (but USUALLY, the lower the frequency, the lower the attenuation).

So let's get a bit technical for a moment. I won't go into too much detail, but lets look at the science behind the signal for a moment. Radio communication is basically a transmitter that produces a signal on a certain frequency (in Hertz (Hz), or a multiple of that KHz, MHz, GHz (Kilohertz Megahertz, Gigahertz)), at a certain power level (watts or milliwatts (thousandths of a watt), that is received some distance away by a receiver that has a certain threshold above the noise level to overcome before it can actually detect that wanted signal. The receiver's sensitivity to incoming signals is usually in microvolts (millionths of a volt). Radio receivers are a rather sensitive lot, they don't take much of a signal to get them to work. That being said, a LOT of things are working against the whole process of getting that signal from your mouth to someone else's ear. The total attenuation from losses inside the transmitter, to losses in the coax feed lines both at the transmitter site, to the receiver's site, as well as antenna losses (or gains), receiver sensitivity and losses, and the attenuation of all of the matter between the antennas, is called "PATH LOSS". We can control some of the factors, but not all.

Before we dive deeper, I want to mention that the math is MUCH easier if we convert the details to decibel form. For example, the sensitivity of most current receivers runs around .1 to .5 microvolts, but the transmitters run from 500mw to 1500 watts. If you convert the receiver sensitivity from .3 microvolts to -118dB/m, and then convert our mild FRS radio transmitter at 500mw ( 1/2 watt ) to 27dBm. You can use the chart at ( http://wa8lmf.net/miscinfo/dBm-to-Microvolts.pdf ) to convert the receiver sensitivity, and the website at ( https://www.pasternack.com/t-calculator-power-conv.aspx ) for the transmitter watts to dBm. What this does is allow you to use simple math now to check and see how much overhead you have on your signal to see if the path loss is going to kill it. 27dBm - (-118dBm) = 145dBm of signal to play with before you can't communicate at all.

The air attenuates HF, VHF, and UHF frequencies at ground level (less than 1km above sea level) at around .06dBm/km. Trees and forests nail the signal a lot harder than just air, but the attenuation varies with the frequencies of the signal involved. HF signals (3MHz to 30MHz) travel fairly well through forests, losing about 3-12db per km depending on how thick the forest is, how wet it is, and whether you are trying to transmit through the trunks or the canopy. This loss increases to 15-85dB per km at VHF frequencies (30MHz to 300MHz), and up as high as 160dB per km for UHF frequencies. This is why CB radios at 26-27MHz (HF Frequencies) work MUCH better than FRS/GMRS radios at 462-467MHz (UHF frequencies), and MURS and 2meter Amateur work somewhere in between the two (they are in the middle of the VHF range). Earth (Soil/Dirt/Rocks...) doesn't pass much in the way of HF, and even less on VHF and UHF. Attenuation of the Earth is WAY up there and not even worth trying to make work.

Going back to the example of the FRS walkie talkie with 500mW of power on 462-467MHz, with a signal overhead of 145dBm, we can see that the signal is not going to make it more than a km through the woods (unless they are mighty thin and you are transmitting through the trunk area and not the canopy) since a dense canopy can eat 160dBm of your 145dBm overhead. So a cheap FRS radio is not going to make it even the first kilometer through. BUT, if there was no forest (say, mountaintop to mountaintop), then that signal could go (145/.06)=2416km. This is why there are many reports of people with cheap FRS/GMRS walkie talkies being heard hundreds of miles away (and why things in space can pickup those signals with ease...). This is all great you say, but you don't live on mountaintops, and neither do your friends you want to talk to. OK, back to the problem at hand. We either need to raise our power levels at the transmitter site, raise our antennas over the obstructions (trees or Earth), OR change our frequencies to see if that helps. Let's kick up the power at first. Let's upgrade the 500mW FRS radio to a 5 watt Baofeng. Now we are cooking with 5 watts (37dBm) instead of 27dBM. 37dBm-(-118dBm)=155dBm overhead at 5 watts transmit power. Better, but still less than the 16dBm of signal eating forest attenuation. OK, so 10 times the power didn't help. Let's change the frequencies down to CB land...

CBs have a power output of 4 watts on AM, or if you have a SSB capable one 12W on SSB. PLUS, the attenuation at HF frequencies is a LOT lower. 4 watts is right at 36dBm, 12 watts is close to 40.8dBm (still not that much more usable power than the 5 watt handheld at 37dBm). But, as we said earlier, the attenuation at these frequencies is MUCH better. Let us estimate the losses of one km of forest at around 10-12dBm. I will leave the receiver sensitivity the same as the other radio as they will be close enough for the "back of a napkin" math. Next we figure the AM transmitter overhead at 36dBm- (-118dBm)=154dBm. And the SSB transmitter overhead at 40.8dBm- (-118dBm)=158.8dBm. It doesn't look that much better than the FRS at this point, but wait... At 10-12dBm per km, you are now looking at 154/12=12.83km before signal loss at the worst for AM, and 158.8/12=13.23km before signal loss using SSB. So a few kilometers COULD be done through the woods with CB, but not FRS/GMRS. Now, these calculations are only working with the space between the antennas Path Loss, and none of the other losses or issues so this is no guarantee either way but at least a good baseline.

My suggestion, go with SSB CB, or try to get above the treeline or the Earth's horizon. The better suggestion would be to get your Amateur radio license (and every one else in the group the same), and that way they can run with 50 watt mobiles, or use handhelds and the already exiting repeaters.

Loup
 

Jonas Parker

Hooligan
Not sure where you are located, but there are several options:

1.) You and your neighbor each get Technician Class amateur radio licenses. Yes, a little work is involved but you will be able to use the 2-meter ham band and use repeaters to communicate if you can't by line of sight transmission. Repeaters are usually mounted on hills or high towers to retransmit signals over a much larger area. You can also use the 10 meter ham band on voice frequencies between 28.3 and 28.5 MHz (or thereabouts), but of course you'll need a different radio than you would use for 2 meters, in most cases. IMO, this is the best option because it is the most versatile.

Most amateur repeaters have some form of emergency backup power, so they should be available for use for quite a while after cell towers and other systems go down.
BINGO! Go to the ARRL website to find the nearest Ham Club. They'll help you get started!
 

CaryC

Veteran Member
If I understand it right, no license is needed using MURS bands?? What kind of distance are we looking at?

The following are the frequencies authorized for use by the MURS:

FrequencyAuthorized Bandwidth
151.820 MHz11.25 kHz
151.880 MHz11.25 kHz
151.940 MHz11.25 kHz
154.570 MHz (also part of business band)20.00 kHz
154.600 MHz (also part of business band)20.00 kHz

I'm a big dummy, so be gentle.
 

Publius

TB Fanatic
While Potato Country is a rather large (and vague) area, knowing a bit more closely about the conditions around and more importantly, BETWEEN the two (or more) houses that you want to communicate with is the main factor... And this goes for ANYONE wanting to communicate with the other locals in your group.

Ask yourself these questions:
  1. Can I physically see (with your eyes, binoculars, or a telescope) the other locations from my house (even if this is only when standing on your roof)?
  2. Can I guarantee that there is only trees and other houses between my house and the other houses?
  3. Do I know for a fact that there is actual Earth between me and the other houses?
The Earth is NOT Flat, nor is it perfectly round. It's rather lumpy, even on the supposedly flatter or rounder parts. Even the ocean gets an attitude and stays rough. That being the case, and added to the fact that everything that is matter works against a RF signal going from one point to another (including atmospheric air), anything between you and the other houses is going to attenuate (reduce) the signal. If you reduce it too much, then you won't have enough signal level at the far end to make the connection reliable. And adding to that fact, the issue that different frequencies are attenuated by different matter, at different amounts (but USUALLY, the lower the frequency, the lower the attenuation).

So let's get a bit technical for a moment. I won't go into too much detail, but lets look at the science behind the signal for a moment. Radio communication is basically a transmitter that produces a signal on a certain frequency (in Hertz (Hz), or a multiple of that KHz, MHz, GHz (Kilohertz Megahertz, Gigahertz)), at a certain power level (watts or milliwatts (thousandths of a watt), that is received some distance away by a receiver that has a certain threshold above the noise level to overcome before it can actually detect that wanted signal. The receiver's sensitivity to incoming signals is usually in microvolts (millionths of a volt). Radio receivers are a rather sensitive lot, they don't take much of a signal to get them to work. That being said, a LOT of things are working against the whole process of getting that signal from your mouth to someone else's ear. The total attenuation from losses inside the transmitter, to losses in the coax feed lines both at the transmitter site, to the receiver's site, as well as antenna losses (or gains), receiver sensitivity and losses, and the attenuation of all of the matter between the antennas, is called "PATH LOSS". We can control some of the factors, but not all.

Before we dive deeper, I want to mention that the math is MUCH easier if we convert the details to decibel form. For example, the sensitivity of most current receivers runs around .1 to .5 microvolts, but the transmitters run from 500mw to 1500 watts. If you convert the receiver sensitivity from .3 microvolts to -118dB/m, and then convert our mild FRS radio transmitter at 500mw ( 1/2 watt ) to 27dBm. You can use the chart at ( http://wa8lmf.net/miscinfo/dBm-to-Microvolts.pdf ) to convert the receiver sensitivity, and the website at ( https://www.pasternack.com/t-calculator-power-conv.aspx ) for the transmitter watts to dBm. What this does is allow you to use simple math now to check and see how much overhead you have on your signal to see if the path loss is going to kill it. 27dBm - (-118dBm) = 145dBm of signal to play with before you can't communicate at all.

The air attenuates HF, VHF, and UHF frequencies at ground level (less than 1km above sea level) at around .06dBm/km. Trees and forests nail the signal a lot harder than just air, but the attenuation varies with the frequencies of the signal involved. HF signals (3MHz to 30MHz) travel fairly well through forests, losing about 3-12db per km depending on how thick the forest is, how wet it is, and whether you are trying to transmit through the trunks or the canopy. This loss increases to 15-85dB per km at VHF frequencies (30MHz to 300MHz), and up as high as 160dB per km for UHF frequencies. This is why CB radios at 26-27MHz (HF Frequencies) work MUCH better than FRS/GMRS radios at 462-467MHz (UHF frequencies), and MURS and 2meter Amateur work somewhere in between the two (they are in the middle of the VHF range). Earth (Soil/Dirt/Rocks...) doesn't pass much in the way of HF, and even less on VHF and UHF. Attenuation of the Earth is WAY up there and not even worth trying to make work.

Going back to the example of the FRS walkie talkie with 500mW of power on 462-467MHz, with a signal overhead of 145dBm, we can see that the signal is not going to make it more than a km through the woods (unless they are mighty thin and you are transmitting through the trunk area and not the canopy) since a dense canopy can eat 160dBm of your 145dBm overhead. So a cheap FRS radio is not going to make it even the first kilometer through. BUT, if there was no forest (say, mountaintop to mountaintop), then that signal could go (145/.06)=2416km. This is why there are many reports of people with cheap FRS/GMRS walkie talkies being heard hundreds of miles away (and why things in space can pickup those signals with ease...). This is all great you say, but you don't live on mountaintops, and neither do your friends you want to talk to. OK, back to the problem at hand. We either need to raise our power levels at the transmitter site, raise our antennas over the obstructions (trees or Earth), OR change our frequencies to see if that helps. Let's kick up the power at first. Let's upgrade the 500mW FRS radio to a 5 watt Baofeng. Now we are cooking with 5 watts (37dBm) instead of 27dBM. 37dBm-(-118dBm)=155dBm overhead at 5 watts transmit power. Better, but still less than the 16dBm of signal eating forest attenuation. OK, so 10 times the power didn't help. Let's change the frequencies down to CB land...

CBs have a power output of 4 watts on AM, or if you have a SSB capable one 12W on SSB. PLUS, the attenuation at HF frequencies is a LOT lower. 4 watts is right at 36dBm, 12 watts is close to 40.8dBm (still not that much more usable power than the 5 watt handheld at 37dBm). But, as we said earlier, the attenuation at these frequencies is MUCH better. Let us estimate the losses of one km of forest at around 10-12dBm. I will leave the receiver sensitivity the same as the other radio as they will be close enough for the "back of a napkin" math. Next we figure the AM transmitter overhead at 36dBm- (-118dBm)=154dBm. And the SSB transmitter overhead at 40.8dBm- (-118dBm)=158.8dBm. It doesn't look that much better than the FRS at this point, but wait... At 10-12dBm per km, you are now looking at 154/12=12.83km before signal loss at the worst for AM, and 158.8/12=13.23km before signal loss using SSB. So a few kilometers COULD be done through the woods with CB, but not FRS/GMRS. Now, these calculations are only working with the space between the antennas Path Loss, and none of the other losses or issues so this is no guarantee either way but at least a good baseline.

My suggestion, go with SSB CB, or try to get above the treeline or the Earth's horizon. The better suggestion would be to get your Amateur radio license (and every one else in the group the same), and that way they can run with 50 watt mobiles, or use handhelds and the already exiting repeaters.

Loup



In the past telling people about SSB CB and that it is a little better and showing a unit that I have it seems many do not have room in their head to deal with that, they want to flip it on and start talking and many cannot do that as they think it's a telephone just hold the transmit button down and they don't understand why no one else is talking and some get into trouble real fast with a mobile unit in a car! Like put the mic down and drive but Nooo they wrap that mic cord around the steering wheel in no time while they keep talking.
 
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LoupGarou

Ancient Fuzzball
If I understand it right, no license is needed using MURS bands?? What kind of distance are we looking at?

The following are the frequencies authorized for use by the MURS:

FrequencyAuthorized Bandwidth
151.820 MHz11.25 kHz
151.880 MHz11.25 kHz
151.940 MHz11.25 kHz
154.570 MHz (also part of business band)20.00 kHz
154.600 MHz (also part of business band)20.00 kHz
I'm a big dummy, so be gentle.
Legally, you are limited to a MURS, 2 watt, type accepted radio using those 5 frequencies. This means that use of another radio on those frequencies is not legal, so no Baofengs or similar on those frequencies if you are trying to fit under the MURS rules and stay legal.

That being said you are looking at about 33dBm - (-118dBm) = 151dBm of overhead, and trees at around 30-40db/km of attenuation, so you are looking at getting at least 151/40=3.775km of forest on average before signal runs out. Not as good as the CB, but at least it has a better chance than the FRS through the woods.

__________


In the past telling people about SSB CB and that it is a little better and showing a unit that I have it seems many do not have room in their heads to deal with that, they want to flip it on and start talking and many cannot do that as they think it's a telephone just hold the transmit button down and they don't understand why no one else is talking and some get into trouble real fast with a mobile unit in a car! Like put the mic down and drive but Nooo they wrap that mic cord around the steering wheel in no time while they keep talking.
I was mainly trying to get people to see the WHY things don't always work when dealing with radio signals, and to prevent a lot of people from going out and buying the $60-$90 bubble pack radios from the box stores hoping to get the completely BS claims of distance on the box when they can't even get a km or 2 through the local woods. Legally, you can't add external antennas to FRS radios and the GMRS ones need a license to be legal. MURS allows for external antennas, but you have to remember that you have 2 watts on VHF, so while the sky (and beyond) may be the limit, five miles of woods will kill it unless you can get the antennas higher than the trees...

I'm a firm believer of "Buy once, Cry once", as well as "Failing to plan is as good as planning to fail."

Loup
 
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