The Definitive Radio Communications Thread

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The Definitive Radio Communications Thread

Well, I have been asked to start this thread for some time now. Asked by at least 6 members that have PM'ed me so here it goes.

First, a little disclosure on my qualifications.

I am a radio engineer. I work for a fortune 100 multinational and I specifically design police/industrial/first responder radios. I've been doing this for 12 years. Prior to this I worked for NASA on the Advanced Communications Technology Satellite Program as a systems propagation research engineer under contract. I also perform research on system propagation and radio range optimization. So I design radios at the printed circuit board level and research methods to maximize their usable range.

So with that said, I am going to lead off this thread with some fundemental topics of communications that my experience tells me are important items to know in a SHTF situation.

First of all, ALL wireless communication devices are radios. Be it a cell phone, a "walkie-talkie", a cordless phone, bluetooth accessory, even an infrared television remote control believe it or not (IR is still part of the electromagnetic spectrum).

When I think of post-collapse society and communications these things come to mind:

1. You want a form of communication that is simple to use.

2. You want communication devices that are mechanically durable and environmentally hardened.

3. You want to be able to communicate in a manner that is as secure as practical. 

4. You want RANGE. That is, the ability to transmit and receive communication, at a minimum audio, preferably both audio and data to the farthest degree possible.

5. You may want to be able to monitor communications (legally) so as to anticipate an ensuing threat and take countermeasures.

6. You'll want to know basic radio technical terminology and why you should care about it. 

7. You'll want to network. We'll talk about public channel communications, private talk groups, repeaters and ad hoc repeater methods, and radio talkaround mode (radio to radio communications).

8. You'll want to get a good handle on equipment such as portable radios, mobile radios (such as in a police car), base stations (ham radios are an example of this), power requirements, battery types, spectrum choice such as Lowband, Shortwave, VHF, UHF, 700 MHz band, 800 MHz band.

Have you already noticed a pattern here? I keep saying RADIOS. Why? Well, it's not from a bias towards what I presently do (I've done satellite, cell phone, and pager engineering too). It's just that two-way radios are the most reliable, rugged, simple, and effective form of communications for a number of reasons:

a. First, the tranceiver (transceiver = transmitter + receiver) circuitry is almost invarably more robust than any other form of wireless. By this I mean reliable, dependable, and repeatable.

b. No infrastructure needed. Which means that you need not rely on a service provider to allow you to interact with others.

c. RANGE. Have I mentioned that this is important?

d. Versatility. With a little knowledge, a cooperative small community of individuals can create and implement their own infrastructure, thus expanding their area of communication coverage, providing for redundancy (a good concept to implement with respect to additional reliability in a dangerous environment)

e. They often are very inexpensive to acquire, and simple to implement and utilize.

I plan on discussing all of these topics in detail, and over time providing as many information links as possible. Perhaps I write a paper for the folks here to keep safe in the even that they need this stuff in a SHTF situation. We'll see. That's a lot of work.

So let's get started, tomorrow. :) It's 06:09 GMT (Greenwich Mean Time, or "Zero-Six-Zero-Niner Golf Mike Tango") and way past my bedtime. In the meanwhile, feel free to request discussion of any subtopic within this subject.

Good night. Talk to you tomorrow.

Morpheus, over and out.

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Re: The Definitive Radio Communications Thread

Thank you. I am looking forward to this thread.

I have accumulated several pairs of simple FRS radios from eBay (Uniden 325s less than $10/pr) and a Sony SW-7600GR+antenna, but have little knowledge of their use or true quality.

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Re: The Definitive Radio Communications Thread

I will also be interested to partake on this thread, esp. with regard to some sort of reliable and expandable system that allows a group of people to stay in touch over maybe 10 square miles of hilly terrain (i.e. not much line-of-sight).  

Thanks for getting the ball rolling, Morpheus!

Viva -- Sager

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Re: The Definitive Radio Communications Thread

You bring up a good point regarding FRS radios. First the advantage of FRS (family radio service band is part  of the UHF band and operates 14 channels with 7 around 462.6000 MHz or so that and the other 7 at around 467.6000 MHZ) are as follows:

1, Cheap. You can get a brand new pair of Cobras, Motorolas, or Unidens for less than a 100 bucks at Radio Shack or Best Buy.

2. Most use AA batteries, which are readily available now. 

3. They're pocket sized so they are physically convenient.

4. They are still in a decent spectrum range (UHF) so the talk/listen range is going to be pretty good. (urban about 2 miles, rural about 10 miles or so)

Disadvantages:

1. Ony 14 channels and very little privacy/security. Anyone can eavesdrop on you.

2. Not very rugged.

3. They often use AA batteries, which limit their use time and require replacement.

Still, for the price EVERYONE that is concerned about Comm (we'll shorten communications to "comm" from now on and get used to the vernacular) should have at least one pair of these.

As for brand any of the three that I mentioned are fine. But you'll want FIXED antennas if you can find them. Motorola and Uniden both offer models with fixed antennas. Why?

RANGE. With RF (radio frequency) power, any discontinuity in the power path of the radio (transmitter/receiver to antenna) is going to cause losses (unwanted loss of power) and limit range. Removable antennas cause a "discontinuity" (sudden change in electrical path, albiet apparently minor to most folks. in the case of the removable antenna it's the type and quality of the connector).

Fixed antennas for FRS are far superior. It's a good thing to remember.

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Re: The Definitive Radio Communications Thread

Tyler. That Sony shortwave is a nice thing to have. Shortwave in general is going to give you the best range for what a civilian is capable of acquiring.

Good rule of thumb: The lower the frequency band the better the range. In fact, all other things equal, it's a law of physics.

Another rule to burn into your head. In an urban environment, range generally falls off inversely proportional to the 4th power of distance and in a rural region approximately the square of the distance.

So, let's say that at 100 meters in a rural region your radio receives 1 watt of power. Since power falls off inversely proportional to the square (power of 2) of the distance, at 200 meters your received power is

(^ = "raised to the power of")

(100/200)^ 2 = (1/2)^2 = 1/4 = 25% of the power at 100 meters = .25 watts. For urban it's (100/200)^4 = .0625 watts.

Very important concept. Power falls off exponentially with respect to distance, therefore radio range is NOT linearly proportional to power. And the exponential falloff is highly dependant on the terrain.

So, a 2 watt radio DOES NOT give you 2x the range of a 1 watt radio AND urban communications are much more limited than rural or "line of sight" (LOS) communications.

Burn that into your brain. It's that important.

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Re: The Definitive Radio Communications Thread

Morpheus,

I need to communicate at a range of 30 miles in an urban environment. Are there any options...Thanks in advanced.

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Re: The Definitive Radio Communications Thread

Great idea for a thread.  I was into ham and CB radio as a kid but that was so long ago that I knew more about vacuum tubes than transistors, if that gives you any indication.

How about some information according to price ranges?  What would be recommended in the $100 and under range, $500 and under range, $1000 and under range, $5000 and under range, etc?

Basically, to use some terminology from the firearm thread, what would the Glock 19, AK-47, and Remington 870 of the radio world be?

What would recommended portable, mobile, and base units be?  Antenna set-ups?  Power sources?

Any information would be greatly appreciated.

 

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Re: The Definitive Radio Communications Thread
JAG wrote:

Morpheus,

I need to communicate at a range of 30 miles in an urban environment. Are there any options...Thanks in advanced.

Yes. A base station with substantial power. Hell, any good ham radio will not only get you across town, it'll get you across continents.

You raise a good point. What equipment, what methods will get me coverage?

1. You want a line of sight (LOS) path which means a tall antenna with an unobstructed "view" of it's surroundings. Ham'ers know this well.

2. You want a decent amount of power. 25 watts minimum. 100 watts perferred.

3. You want antenna with high GAIN*. Preferably at LEAST 3 dB**.

4. You want low frequency communication. The lower the frequency, the longer the wavelength. The longer the wavelength the better it propagates. Range is DIRECTLY PROPORTIONAL to wavelength and hence inversely proportional to frequency. That's why ham folks use shortwave. It's relatively low frequency.

BTW. Ham folks know what they're talking about. Listen to their advice. Any ham'ers feel free to jump in. The more voices the better.

* Antena Gain: The apparent increase in transmitted or received power caused by directional focusing of the antenna. Think of it this way. Light intensity is measured in something called "lumens". OK, now think of a flashlight bulb connected with simple wires to a battery. It's "light power" is not at all that impressive.

Now put the bulb (analogous to the transmitter OR receiver.. concept is identical, that's called the axiom of reciprocity) in front of a reflector (analogous to an antenna). The light "power" is focused, directed, or concentrated. Same electrical power producing the same "light power", but it's all concentrated in one direction. Antennas do the exact same thing. They can be highly directional, like a satelite dish (which if you think about it, is like a reverse flashlight reflector... reciprocity) or partially directive, like a ham tower where the RF power is "focused" in a doughnut shape parallel to the ground.

dB = decibels. dB are a measure of RATIOS. Nature you see, often expresses herself in very non-linear ways. I already demonstrated that by showing you that twice the transmit power does not give you twice the range. With radio communications, a good receiver has a dynamic range (difference between the lowest effective power that it can receive and the highest power without causing problems) can be orders of magnitude.

For instance. the radio that I just finished designing and just went to market globally is a portable police radio that can receive radio signals effectively in the range of 5 watts to .0000000000000005 watts or 1x10^(-16) watts. That lower number is 50 thousandths of 1 trillionth of a watt.

So, ALWAYS in radio communications you will see the unit of decibels. Because it is not practical to work with such drastic extremes, engineers and field techs convert the number to a more convenient scale. For power the formula is very simple. Remember I said a decibel is a ratio. For gain it is the ratio of the flashlight intensity with a reflector vs without. For power it is the ratio of the radio's power to some convenient value such as a watt (dBW) or milliwatt (dBm).

Antenna Gain (dB) = 10*log10((power density in the antenna beam)/power density if the transmitter's power were evenly distributed in all directions))

Power (dBW) = 10*log10(Transmitter power/ 1 watt) = 10*log10(transmitter power). Note, you can equally substitute receiver sensitivity (the lowest received power that a radio can effectively pick up) into the equation.

Power (dBm) = Power (dBW) +30. You'll see this unit a lot!!!

Example. You have a 5 watt radio. It's power in dBW is

P(dBW) = 10*log10(5 watts/1 watt) = 10*log10(5) = 7 dBW.

P(dBm) =7 + 30 = 37 dBm.

I am not trying to be geeky or too technical folks. Ask the ham community. If you want to really be able to use radio communications effectively, you need to know this stuff. I know it's dry, but trust me on this. Just let it percolate in your head over time and it'll all come together as one big "Eurecka!"

You will see decibels everywhere you deal with radios. So might as well learn it and understand it. Remember, it's just a ratio. And it's used because of the extreme spread in values that the physics of radio communication encompasses.

So, that radio I shipped. It can receive a signal range from 0.0000000000000005 watts to 5 watts. In dBm that's a range of -123 dBm to 37 dBm. What's easier to work with. watts or dBm? See?

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Re: The Definitive Radio Communications Thread

For Ham radios I would defer the specific brand names to hardcore ham operators. I'll say it again. These guys are good. Real good.

But, look for radios that have very high sensitivity. You'll want a rated sensitivity of at LEAST -110 dBm or lower.

Look for high Adjacent Channel Rejection (ACR). This is the radio's ability to reject interference from nearby channels. 60 dB or better. (see, those dB pop up everywhere!!! LOL).

Transmit and receive Hum and Noise specs of at least 40 dB. It's a direct measure of audio quality. For digital you want as low a BER (bit error rate) as possible.

If possible, get dual mode radios (analog and digital).

Any audio distortion spec of 3% or lower is good enough. You'll start becoming annoyed at the 5% level.

Narrowband antennas have better GAIN than wideband antennas (you'll see these words in the specs). Better to need two antennas to cover your radio's spectrum and get superior range than one antenna that cuts your distance by 30%. The solution is simple. Just program your user channels to the frequency range of just one of your antennas.

Look for FM radios with high DEVIATION. Deviation is operating bandwidth on either side of the carrier frequency. For example, you're on 162.025 MHz with a 25 kHz channel (which means the channel occupies 12.5 kHz on either side of the carrier, or occupies 162.0125 MHz to 162.0375 MHz). A high deviation would be 5 kHz on either side of the carrier. This is where the information is modulated*. The wider the spread, the higher the quality of modulation, the better the range and/or bit error rate. 

Look for radios where the user can program the channel bandwidth. For FM, a smaller bandwidth gives you better range. But a larger bandwidth gives you better audio quality. It's a tradeoff and there are situations where either are more desirable.

Look for radios that have a lot of pre-programmed channels (if they are old) or the capacity to program a lot of channels into them. At the $5K range start looking at more at , power, antennas, encryption, and features, in that order of importance. Features are nice, but a luxury in my opinion.

Look for radios that allow talkgroups and scan mode. Those are handy features. A talkgroup allows a bunch of users to share the same channel and communicate. Cops use them as a must-have.

*Modulation: Without being too technical, it's how a radio transforms voice and/or data into a mode that can be transmitted over the air. FM, or frequency modulation, varies the transmit frequency in proportion to the microphone (mic) audio intensity. AM varies the amplitude, or transmit power, in proportion to said mic audio intensity (or power really).

FM is superior to AM, period. It has far better noise rejection and something called the FM capture effect (to be discussed later).

Under $100? Go online and get 5 watt VHF Motorola/Uniden/Standard/Kenwood radios, old and used. Don't care if they're 15 years old. They're still mil-spec (military spec) radios and will outperform the "pretty", "sexy" modern consumer stuff with the nice displays and cool colors.

Analog is in my opinion superior to digital with respect to two-way simplex* communication. Better range in general, and far superior audio quality. It's a myth that digital is always better. That said, digital has some very compelling arguments in favor it which I'll discuss later.

*Simplex: Any radio where the use can talk/listen but not do both at the same time. Simplex radios have either VOX (voice activated transmission) or a PTT (push to talk button). By contrast, a cell phone is a DUPLEX mode radio where the transmitter and receiver are both simultaneously active.

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Re: The Definitive Radio Communications Thread

Never underestimate the importance of a high quality antenna for your base station or mobile radio. And always keep the junk between your transmitter and antenna as minimal as possible (cable length, connectors, ect).

 

A great radio and a crappy antenna add up to a crappy radio. It's worth putting some money into. It's axiomatic that your communications system is only as good as the weakest link in it. So have a good base station, a good antenna for it, and good portable radios. The worst performer of the three will determine the overall performance of your system.

Also, a good communications system would have:

Portable radios (handheld)

Mobile radios (mounted in a vehicle or even suitcase)

A good base station.

For 30 mile communication, mobile used police radios will do the job if you have a good antenna. For long haul, go with shortwave. Remember though, shortwave cannot talk to police radios and vice versa. So tailor your purchases to your needs.

For local community go with the mobile. For large-scale interaction go with the ham radio.

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Re: The Definitive Radio Communications Thread

The power should be in the transmitter although you can boost it substantially with an amplifier. But remember this. Being able to transmit farther does not equate to being able to receive farther. And any amplifer that you place in front of your equipment (between the transceivers RF jack and your antenna) ABSOLUTELY MUST BE, let me repeat that, ABSOLUTELY MUST BE a low noise amplifier.

All amplifiers have a specification (spec) called a "Noise Figure" (NF). It's it's any worse (higher) than 3dB, then don't even consider it. 2 dB is probably most likely.

Repeaters have the same spec although 3 dB or higher is tolerable.

 

Signal-to-Noise Ratio (SNR): The ratio of received RF power to total noise power in the receiver channel. The noise sources are atmospheric, interference, and circuit generated noise in the receiver. Low SNR = crappy signal strength, high SNR = great signal strength and hence great intelligibility (ability to understand the message). Simple as that.

Noise Figure: The ratio of an amplifiers SNR at the output to it's SNR at the input. This spec indicates how much the amplifier "mauls" or degrades the signal integrity while it's boosting it.

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Re: The Definitive Radio Communications Thread
SagerXX wrote:

I will also be interested to partake on this thread, esp. with regard to some sort of reliable and expandable system that allows a group of people to stay in touch over maybe 10 square miles of hilly terrain (i.e. not much line-of-sight).  

Thanks for getting the ball rolling, Morpheus!

Viva -- Sager

Please do Sager. The more folks the better. I'd also like to see some of the ham folks show up.

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Re: The Definitive Radio Communications Thread

Thanks for starting this thread!

It sounds like the simple AA battery powered walkie-talkies are good for short distance communication (<=10 miles) and a ham radio is better for longer distances(obviously). I've been reading about rechargeable AA batteries, including battery solar chargers so I think that would take care of the battery drain issue.

If anyone wants to jump in about HAM radio certifications, which one to get, where to start. I know AARL has a handbook they produce for certifications, but again, which one to go for? If I want to be able to chat with family 500 miles away or 4,000 miles away, what do I need?

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Re: The Definitive Radio Communications Thread
joemanc wrote:

Thanks for starting this thread!

It sounds like the simple AA battery powered walkie-talkies are good for short distance communication (<=10 miles) and a ham radio is better for longer distances(obviously). I've been reading about rechargeable AA batteries, including battery solar chargers so I think that would take care of the battery drain issue.

If anyone wants to jump in about HAM radio certifications, which one to get, where to start. I know AARL has a handbook they produce for certifications, but again, which one to go for? If I want to be able to chat with family 500 miles away or 4,000 miles away, what do I need?

http://www.arrl.org/

Lots of power, long wavelength, big, tall antenna with lots of antenna gain. When I worked for NASA, the satellite that I was working with was a geosynchonous orbiting satellite (GEO) meaning that it was 26,000 miles or 40,000 km "up".

That's a tall antenna, LOL.

It had a mere 5 watt transmitter. Worse, it was SUPER high frequency. 30 GHz (that's 30,000 MHz) so it's path loss (L, power loss per mile or km) was atrocious.

So, you're asking, how the heck can you transmit 26,000 miles with a low power transmitter and such a high frequency????

Answer: The antenna. A parabolic reflector (or in human terms, a round satellite antenna mounted on.. surprise, the satellite. LOL). The flashlight analogy is perfect here since the antenna, a "reflector" does the same thing that a flashlight reflector does for it's weak light bulb (it's "light transmitter"). It focuses the power directionally in a narrow beam. Towers do something similar.

The antenna had a large antenna gain. 63 dB to be exact. (all public knowledge).

What does 63 dB equate to? Well, reverse the equation for decibels. Let's find out:

63 dB = 10*log10(x watts per watt) or log10(x) = 63/10 = 6.3 or x = 10^(6.3) = 2,000,000.

The antenna had a gain of 2,000,000 watts per watt of transmit power. So the Effective Radiated Power (ERP) was 10 million watts. With no obstuctions like trees and buildings we we're getting great reception.

From a 5 watt transmitter.

And our ground antenna had a ERP (ERP is a term used for antenna gain. You'll see that a LOT) of 57 dB or a wee bit more than 500,000 watts/watt. So when we got the signal, our antenna boosted it by half a million. See how it works?

A GREAT antenna is essential. It can compensate for lack of juice. I'll keep emphasizing that over and over and over.

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Re: The Definitive Radio Communications Thread

Thanks for the info Morpheus.

BTW, I live about 15 mins south of NASA's Johnson Space Center, any chance you once lived in my neighborhood?

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Re: The Definitive Radio Communications Thread

No. I worked out of Florida on the West Coast.

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Re: The Definitive Radio Communications Thread


Quote:

Basically, to use some terminology from the firearm thread, what would the Glock 19, AK-47, and Remington 870 of the radio world be?

I might be of service here.

In keeping with the general areas of use of "pistol/rifle/shotgun", radios can likewise be broken into catagories.
Short range: FRS/GMRS which are limited to a practical maximum of 2 miles, and are used predominately for team or family communications over a short distance; for example communicating from a "house" to a garden, forest or lake nearby, a group initiating an ambush on road agents or hostiles and the like.

For the "short range" medium, a small, tough radio would be the best, and the Motorolas have an excellent reputation for the FRS/GMRS bands.
For the specific radio, I do not know which would be the "Glock 19", but this would certainly be the "pistol" of the radio arsenal. All the disadvantages that Morpheus laid out apply.

The AK/Rifle would certainly be the Yaesu VX7R(B). This is a Tri-Band HAM radio that can operate on bands up to 6 meter. This radio fills the "intermediate" range, and can  easily relay messages up to 25 miles. With access to repeaters, or other mobile relays, you can extend that range to several thousand miles, though advance knowledge (that I don't possess) would certainly be required.

The VX7 is very robust, can be equipped with either a AA battery adaptor or a LiON battery. Typical range is about 10 Miles, and the Radio itself is capable of putting out 10 watts, so an upgraded antenna can certainly boost your output - just make sure your system can handle it, and you've got a good handle on how you'll replace the energy used.

Using 2 watts, the radio can last for several days if you ration your use, and use pre-determined monitering times. Though this can reduce security, I believe that it has a place in your overall communications plan.

While the VX7 is capable of handling 90% of the situations you'll ever need to handle, the Yaesu FT897 is sort of like the "Dragunov" to the VX7's AK. Though it's less mobile than the VX7, it's more powerful and has more features. In addition, both of these radios can be equipped with RTT (Radio-teletype) Morse, and Packet - which will allow you to download and transmit digital (computer) data.

Further note: Pete said:

Quote:

*Simplex: Any radio where the use can talk/listen but not do both at the same time. Simplex radios have either VOX (voice activated transmission) or a PTT (push to talk button). By contrast, a cell phone is a DUPLEX mode radio where the transmitter and receiver are both simultaneously active.

The VX7 is both a Simplex and DUPLEX capable radio. Be aware that when you first get it, it will be pre-set to DUPLEX.

Finally, the "shotgun" of the radio world would, in my mind, without a doubt  be a CB.
Though the CB channels will be obnoxiously crowded - they'll be a valuable source of information and a way to keep in the "loop" with the common folks who do not have access to HAM radios.

So I look at my communications plan like this:
After you've established what you'll ues for your Radio and Power Source;
1. Family/Team Communications0-2mi (FRS/GMRS)
2. Town/Local Area Comms. 1-5mi (CB)
3. Regional Comms. 5-150mi (HAM)

In addition to this, each "layer" must have pre-determined frequencies that are monitered by whoever is the "network administrator". Think of one person who'll have all three layers and the ability to operate them with proficiency. This person should be able to moniter the channels, set up and initiate your communications plan using something like this:
P - Primary Channel
A - Alternate Channel
C - Contingency Channel (In case of compromise)
E - Emergency Channel

With each station rotating each day.

The primary channel, used for the day for relay of general news and information gathered from the CB, local area, word of mouth and happenstance;

Alternate Channel, used for HAM radios that are operating in the local area, but do not want to clutter the primary channel (think of sending a trading party into town; they would use the "alternate" channel instead of the primary)

Contingency Channel, in case you begin having erroneous or compromising messages or monitoring. Any invasive threats should initiate the contigency channel use; via a code word - for example, if you become aware of monitoring a message like "Code 9" would simply mean switch to the contingency channel for further instructions.
Beware! This is illegal at present due to FCC regulation. Please do not engage in illegal activities on your HAM radio! Practice on your FRS/GMRS!

If an emergency were to occur, the information should be relayed to the family/team via the GMRS/FRS so they can assemble, mobilize and neutralize the problem, and very probably switching to a 'new' PACE plan.

The benefit of the VX7, is it can be set up with 230 "preset" channels, which means you can pre-program the channels you intend to operate on, and vary them accordingly. Once your team has set up their communications channels, you can very easily switch your channels.

A final note; Learn Morse, or write it down. This forum of communication can be broadcast with extremely minimal technology, and even if you don't intent to broadcast, the ability to receive Morse and decode it will never do you any harm.

Morpheus, thank you kindly for the excellent thread bro... I'm very glad to see this show up.

Cheers,

Aaron

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Re: The Definitive Radio Communications Thread

Outstanding Aaron. Simply outstanding.

 

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Re: The Definitive Radio Communications Thread

Aaron. You brought up a critical concept.

Relaying.

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Re: The Definitive Radio Communications Thread

Morpheus,

Thanks for starting this thread. The subject of radios came up at our local groups meeting last week so your timing could't be more prescient. I'm going to get better educated by re studying your posts and then contacting some local Ham Radio  buffs.

Coop

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Re: The Definitive Radio Communications Thread

Morpheus,

Thanks for starting this thread. The subject of radios came up at our local groups meeting last week so your timing could't be more prescient. I'm going to get better educated by re studying your posts and then contacting some local Ham Radio  buffs.

Coop

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Re: The Definitive Radio Communications Thread

Morpheus,

A solar roll, roll of coax and a ICOM 2 meter is not NOT an option. ;)

The problem with relaying is that it opens the message up for further exposure. With repeaters, you're likely to start running into maintanance issues right away after things start breaking down, so be sure not to include those in your "plan".

I'm still not convinced that a laptop, Solar Roll, and packet radio isn't the best way to go for "serious" long distance communications. The security would require a greater level of sophistication to get the information to aquiesce, but the technology to send the messages isn't drastically beyond hooking up and programming the radio using computer technology  that we all already possess (to the best of my knowledge).

The Solar Rolls are not "cheap", but considering what you're getting, they're not expensive.
How much is communication worth to you?
If you're working out of a vehicle, a Deep Cycle Battery  can be a HUGE asset - allowing you to continue using both the laptop and the radio.

There are several diversionary tracks this conversation could take, but I think it's best to wait, and keep talking about the function level of Radio comms.

Cheers,

Aaron

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Farmer Brown
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Re: The Definitive Radio Communications Thread

Morpheus,

This is great.  Many thanks!

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Re: The Definitive Radio Communications Thread
Aaron Moyer wrote:

Morpheus,

A solar roll, roll of coax and a ICOM 2 meter is not NOT an option. ;)

The problem with relaying is that it opens the message up for further exposure. With repeaters, you're likely to start running into maintanance issues right away after things start breaking down, so be sure not to include those in your "plan".

I'm still not convinced that a laptop, Solar Roll, and packet radio isn't the best way to go for "serious" long distance communications. The security would require a greater level of sophistication to get the information to aquiesce, but the technology to send the messages isn't drastically beyond hooking up and programming the radio using computer technology  that we all already possess (to the best of my knowledge).

The Solar Rolls are not "cheap", but considering what you're getting, they're not expensive.
How much is communication worth to you?
If you're working out of a vehicle, a Deep Cycle Battery  can be a HUGE asset - allowing you to continue using both the laptop and the radio.

There are several diversionary tracks this conversation could take, but I think it's best to wait, and keep talking about the function level of Radio comms.

Cheers,

Aaron

Agreed with the scope. The focus should be on implementation and technical requirements. I see a LOT of questions regarding "what do I need to transmit "x" distance".

I'll present a white paper here that will address that in general terms and layperson language. I think understanding the concept of propagation and link budget are very important. If folks can grasp that concept they'll have 90% of the technical aspects they'll need to thrive.

I'll focus on the technical. How about you focus on the tactical? Whaddaya think?

And we need more ham folks in here! LOL

 

Disagree with relaying. It may someday be critically necessary to call for emergency help and folks need to understand how to do it.

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Re: The Definitive Radio Communications Thread
Quote:

I'll focus on the technical. How about you focus on the tactical? Whaddaya think?

And we need more ham folks in here! LOL

Disagree with relaying. It may someday be critically necessary to call for emergency help and folks need to understand how to do it.

Sounds good to me, and I couldn't agree more. The more Operators we have, the better. Honestly, I am a Ham Radio Owner.
My skills at operation are extremely limited, and I can't speak with any real authority on anything other than the administrative ends. The Technical ends have eluded me, and I'm extremely rusty - thanks to the military.

With regards to relaying, I could be convinced. I think that once local security has been established, none-sensitive information needs to be disemminated to other towns, and a "schedule" of sorts should be established; 'at such and such a time, this town calls that town, then that town calls the other town 30 minutes later' or some such. In this way, I think that relaying is absolutely critical.

But relaying information that's critical to an area's survival, or gives security issues to an unknown recipient definately gives me pause. Radio discipline needs to be established before every one starts going on the bands jabbering... I remember listening to police scanners and communications from New Orleans during Hurricane Katrina - and brother - there was a lot of information that "made" itself available.

Cheers, and eagerly awaiting more on the subject...

Aaron

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Re: The Definitive Radio Communications Thread

Cool Stuff

 

Could you addres ways to store RF devices to safe guard them  in the event of a EMP or Solar storm that could wipe out all electric circuits causing the comunation grid to go down, not to mention the GRID to go down which would be TSHTF

 

Thanks

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Re: The Definitive Radio Communications Thread

A metal Mesh surrounding the equipment generally referred to as a "Faraday's Cage".
http://en.wikipedia.org/wiki/Faraday_Cage

That said, It's my personal opinion that on the list of things to worry about, EMP comes right behind "Asteroids".
Weaponizing EMP would have to happen first, and then you'd have to get caught in a relatively isolated blast zone.
If you're worrying about Nukes... well, anything caught in the EMP's effective range is destroyed with the blast, so it's not too worrysome.

I'm certain that the type and intensity Solar/Geomagnetic storm that knocks out grids are worth considering, but again, weighed against the unlikeliness that you'll personally be effected... I'd say it's a relatively low concern as well.

Cheers,

Aaron

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Re: The Definitive Radio Communications Thread

Morph:

This is an old thread but good one.  Im hoping for some revival.  

I have been considering ham radio for many reasons. First,  I am an information junkie who would go out of his mind without some word from the outside in an emergency.  

Second, I live in a small town in WY.  I get out in some REALLY remote wilderness areas and public lands.  Most of the time, there is no cell coverage until one can see a town or tower.    When I drive, I use text on the cell because it will usually get through but if it doesnt, I get a message that it didnt.  Most of the texts are things like:  "In Basin, home at 6:30"  Or, " call _____ and let him know I will call him tonight."   Or, "what is the weather like on there?  Should I avoid route ___ or stay  in ____".  Pretty much just utility but potentially lifesaving information too.  My whereabouts, when to expect me home, things of that nature. 

Third, Im a total geek that got turned on to HAM early in life.  A neighbor had a ham set up in an old farm house and about a dozen antennas sticking up on every high barn and high point.  He had collected all that stuff from military surplus and it was his only hobby.  He was trained in the Navy as a radio operator.   He would sit in front of that equipment every waking minute.  There was a speaker in the barn where he would listen to morse and voice from all over the world.  He would interpret the Morse some times in real time.    Im an engineer who likes hi tech BUT also likes the old school tech too.  I like to understand the mechanics of what Im working with - not just take whatever the black box spits out. 

I think the cell tech is pretty iffy.  I mean that could go away very quickly - like it did in Egypt.  I know of those GPS spot receivers that send basic messages etc but I dont really want to pay for the service and SAT tech seems a little dicey too. 

I am currently study for a Technician license.  I have taken a few online sample tests and have passed so Im feeling like Im on my way.  I will take the General after I get some hands on. 

My first priority would be to be able send a SMS text message or email via ham.   Im not afraid of learning morse code and have started doing that.  Is there away to send morse and have it recorded on a frequency where it can be picked up later by my not-so-geeked-out wife?  There are Iphone apps that decode morse so I gotta believe there is a way to this.  I have heard of Packet radio that can send digital data - is that an avenue to explore? 

QRP is grabbing my attention.  The idea of using low power and intelligent application of antenne/propagation really intrigues me.   Im thinking  perhaps of a Yaseu FT-817 or ICOM  IC-703+ might be a good start toward exploring the possibilities?  Or, should I go with some more wattage to get over the learning curve before diving into the deep end? 

Any help would be greatly appreciated!

 

 

 

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