Ok, school me on coms

Chorky

Observer
As the title suggests. I've done a lot of reading over the last few years, and have now just simply become overwhelmed with so many options and technologies - especially relating to HAM's. There seems to be some contradicting information, so I was hoping for input to sort it out, or at least be pointed in the right direction.

I am a big supporter of multiple facets of coms. I always run the standard CB, and have been wanting to dip into the HAM world also. However, now there is a big push it seems for the additional FRS/GMRS, and now even sending data through HAM freqs?

So, CB and sat options aside, and forum searching aside (which I have done plenty!), I'm curious to hear where are some good sources for solid info and data on:
HAM - yes I realize you need a license, and am hoping to find a local 'club' to work on that with
FRS/GMRS - yes I realize you need a license for some of the freqs
Celle extenders
Other options I'm not aware of (not including InReach)

From my understanding, weboost is one of the better options for cell extenders.

I have recently considered the addition of the Midland MXT400 to add to the coms options. It is my understanding this works on FRS and GMRS freqs?

But as for HAM, here is where I am honestly totally lost. I certainly want to have emergency coms options, but also want to be able to just chat with random people all over the place. I have for a while now considered the Yeasu Ft-875 for its versatility; however, have only recently (in the last few months) seen multiple forums discussing the disadvantage of having an 'all in one' radio, and instead recommending splitting it up to two radios, I think one for HF, and the other for UHF/VHF? Now, to compound this, police/fire/emergency responders - are they also on HAM freqs as I understand it, or do you still need a dedicated 'scanner' to stay up to date on happenings? And what about this whole 'data transfer' and 'texting' and 'internet for computer' stuff I have been reading about lately? Likely much more than what I need, although in specific situations it might be nice to have the option if this in fact is legit.

Lastly - any personal experiences with the President McKinley (CB)?

In any case, the HAM side of things is my biggest confusion point, and due to recent readings, I am now quite confused. Looking forward to getting some direction form the community! Thank you in advance (I may be slow to reply).
 

DaveInDenver

Middle Income Semi-Redneck
The disadvantage of an FT-857 or similar HF/VHF/UHF is that you are only able to operate one band, one mode at a time. Also that radio in particular isn't the most versatile compared to more dedicated FM mobiles. By that I mean the way the interface works, the buttons, display, memories, scanning aren't super intuitive, having the ability to in some cases use two frequencies simultaneously (perhaps doing APRS).

BTW, APRS is the digital mode that you're probably referring to. This is an audio-based protocol that lets you send packet data over the air. Often this is position beacons but can be messages. Normally those messages are point-to-point, like a text. But there are APRS radios (called digipeaters, digital repeaters) that connect to the Internet. This lets your position show up on websites (http://www.aprs.fi for example) but also people have set up SMS/Text-to-APRS gateways and email-to-APRS gateways. Those take an APRS message sent on the RF side and re-route them as a cell text or Internet email. And it's two-way, so someone can send an email that shows up as an APRS message to you while you're in the field.

I have an FT-857 and it's a great radio, crams a lot in a small amount of space but I would put it way down the list of recommended first radios for a new amateur operator. Also, FWIW, I don't use it mobile anymore since I find mobile HF to be much too distracting to be of much use. Working HF bands IMHO is something you sit down and do in camp.

First responders generally do not operate on amateur bands and most aren't particularly radio savvy anyway. You might find pilots and SAR to have ham capability or at least may be hams on the side, but whether their primary radios are ham is hit or mostly miss. The flip side of that is being an amateur radio operator does not give you any special privileges to use police or fire spectrum. It's illegal to operate beyond your authority unless there's a dire need to do so, an immediate risk of life or property.

Some ham radios can receive police and fire traffic, but depends on several things. If they are using 2m or 70cm analog FM then likely any ham radio will work to receive (but not transmit). That is next to zero now with most agencies. Many have gone to upper UHF, 800 and 900 MHz. Some are still analog but many have converted to digital modes, usually P25. There's nothing illegal about owning a radio that can pick them up. That's usually surplus commercial equipment made by Motorola, Kenwood, Vertex, etc. It's not all that cheap, though, and of fairly limited use (but not zero) for hams. It's something you'd experiment with as a ham. Beyond this some have gone to encrypted digital, in which case you will not be able to decode it at all.

So, the answer to the first responder question is that you'll be better off with a dedicated scanner to monitor that traffic in the long run. Some highway patrols may still monitor CB, not sure about that. It's unlikely you can plan to communicate directly with a cop or fire crew and even if you determine a way to do it testing that it actually works will get you a knock on the door from the FCC at minimum.

The MXT-400 is a GMRS radio. So it works on the GMRS frequencies and the shared GMRS/FRS frequencies. It does not operate on FRS (typically the cheap blister pack radios).

The advice I usually give is getting your ham license is never a waste but the decision on what radios to install depends on what you want to do with it and who you're planning to talk to. Most ham clubs aren't 4WD clubs, so if it's a hobby you want to do anyway then it's very flexible and you will usually have someone to talk to and repeaters to use. If your group of buddies are using CBs then there's no point to ham or GMRS. If you're trying to get people into radio you will probably have better luck convincing them to go GMRS.
 
Last edited:

BigSwede

The Credible Hulk
^^ great information.

Ham is for hobbyists, and trail comms is about 0.1% of what you can do with ham if you are into it... hence your bewilderment, which I share with you. A discussion with a ham hobbyist will usually unleash a flood of obscure acronyms and terms that make your head swim.

But it doesn't necessarily have to be that way. Our overlanding group went to ham about 5 years ago because CB wasn't cutting it for range and clarity. Only a couple of the group are into ham as a hobby, the rest pretty much use it for trail comms only. We created a "recipe" of recommended simple 2-meter radios, antennas, and coax so a club member could just buy the stuff without doing all of the research if they weren't interested in doing so. This cured a lot of resistance for the conversion from CB.

Having said all of that, if I was starting the process today for our club, we would be looking at the GMRS options pretty closely, due to the CB-like simplicity of use.

But as above, it strongly depends on who you will be talking to, and what radios they have. I have been on runs where some have CB, some have FRS, and some have ham, it it is a bit of a nightmare to try to listen to all of them at once.
 

DaveInDenver

Middle Income Semi-Redneck
The point about being a ham first, 4WD person second is key. If there are no hams in your group already then the value is lost. Like BigSwede mentions, you need mentors to help with radios when you go with ham unless you're willing to dig in and learn the details. Getting frequencies and repeaters working, understanding operating techniques, just playing around with radios has to be something you're willing to do.

Our 4WD club is similar, a few of us are Elmers (a ham term for mentor, teacher, etc) and we have lots of appliance operators (this is actually kind of a derogatory terms for hams who don't understand their radios). These people have some various understanding but mostly we have standard programming files and as long as they select one of the common radios (FT-7900, FT-2900, Baefongs, etc.) that other people have they are essentially using the equivalent of CB or GMRS.

I think having everyone go ham was and still is a mistake long term. I love that the hobby has been rejuvenated but it's created plenty of problems, too. I think having people embrace GMRS makes the most sense. We hams will figure out how to make it work and it has all the primary positives of ham: UHF, FM, higher power, repeaters.

I also think there's some misconception about what is possible with HF. This is something that can work well for remote travel. Using maritime travelers as an example, they often have HF ham radios for long distance communication. But you really have to want to operate HF to understand how it works and the technical details behind it. It's just as equally likely the whole thing will confuse and frustrate you if your expectation is based on CB or channelized VHF FM.
 

sonoronos

Usually broken down on the side of the road
On your question about SSB CB radios, in theory, I think it's a good compromise on increasing CB range vs having to go HAM.

You get to talk with your non-SSB, non-HAM CB buddies, then, on the same radio, switch to SSB to talk to anyone else with an SSB CB radio. You get 12W PEP - still not a lot of power, but at least you're keying up outside QRP :)

If I were to buy another CB today, I'd personally skip past the standard AM transceiver and go with an SSB unit with built-in SWR meter and AM capability.

I'm still a little unsure of why "comms", "ham" and "emergency" always seem to appear in the same post when it comes to radios. To me, these are all totally different things, and emergency is really almost entirely based on having another person to communicate with 100% of the time. I guess maybe the implicit question is, "if I had to communicate with a buddy who was guaranteed to be listening to me the entire time, what should I choose?"

The reason why that becomes difficult to answer is because answering that question is totally unbounded. I mean, why not go with 1.5kW on 40m? :) You get into the cycle of going, "well....I don't want to do xxxx because of yyyy..." and it becomes an endless loop.
 
Last edited:

DaveInDenver

Middle Income Semi-Redneck
Sure, there's no reason to keep doing full carrier, double sideband AM other than since that's what everyone has for receivers. It's not trivial to get an AM receiver to demodulate suppressed carrier, single sideband (SSB) without modification. You can make sense of an AM signal with a SSB radio, but not the other way.

The question then is if everyone needs to buy new radios why would you pick low band VHF at 11m with it's physically long antennas and 12W PEP limit when you could buy 70cm radios with short antennas and a 50W limit? Plus with GMRS you get FM to boot, so the clarity and interference are improved.

In ham it's the opposite, everyone has SSB radios so it's something of an oddity to find people using AM with a carrier. Those tend to be wanna-be broadcaster that have something of a vanity streak IMO. If a fella wants to do SSB on CB it's because he's interested in better range and my assertion is just go ahead and be a ham. There will be people to talk to and usually a civil attitude. Then you also get band nimbleness, so 10m not working, try 6m, 20m, 40m or 80m!
 

sonoronos

Usually broken down on the side of the road
All fine points, Dave. I just don't agree it's an either - or.

I don't think this is a competition of ham vs CB. I don't think HF exists to the exclusion of CB or SSB CB. I don't think it's fair to say, "Why bother with SSB CB when you can get your ham license and go crazy with 2m/70cm". IMHO CB exists on a different planet, maybe even galaxy, universe, or even dimension from ham radio.

Choosing one is not at the exclusion of the other.
 

wirenut

Adventurer
Ham, or amateur, radio is a vast hobby encompassing just about any type of communication you can think of. Trying to understand everything is pretty much impossible even for someone who has been into it for years. There's just too much variety. There are radios that will allow for voice communication as well as sending text messages, position reports, pictures, etc. As you add features the radios get more expensive and more complicated. If you find all that stuff interesting and you like to play with technology then have at it. There are ways to communicate thru amateur radio satalites, world wide email based systems (Winlink), and just about everything else but I don't see much value in those for the average person just out exploring and needing to communicate somewhere for basic help or enjoyment.
For most peoples trail running and emergency communications a simple 2 meter radio with a good antenna is about all you need. Then, you need to learn how to use it, learn the local repeaters and simplex frequencies, and learn some of the other local operators. It's not just a matter of sticking a radio in your vehicle and never turning it on until you get stuck. That's not the time to try and learn how it works and what repeater you can hit. If you have a repeater in your area with an autopatch you can use it to make phone calls from your ham radio. These used to be very common before everyone had a cell phone. Often the owner doesn't hand out the access code's unless your willing to contribute to the expense of the machine. Back in the day if I need help I used my ham radio mostly to make a phone call rather than talk to another ham for help. I did talk to plenty of other hams thought. I've been licensed over 25 years and have made many great friends thru the hobby.
 

comptiger5000

Adventurer
I'd say a combo of CB/SSB and GMRS should cover quite a bit of communication needs (especially with a group on trails and such) with a pretty low barrier of entry as far as knowledge, etc. Having both covers having something with practical handhelds (GMRS) as well as more than 1 frequency band to give options for working around local interference or just depending on what works better with the surrounding terrain.

The biggest downsides to CB are that most good units are physically large and the antennas are necessarily tall as well. But as far as performance, a good setup is adequate for most trail purposes. Unless I'm talking to someone with a potato for an antenna, I've never really wished for more range from the CB in a trail environment (with a fairly good setup on my end, older Cobra 148GTL and a Wilson 2000 on the front fender of the Jeep, top of the antenna being about 8.5 feet off the ground).

HAM would be a good step up in terms of options, but for casual use it's a much bigger deal to get into.
 

DaveInDenver

Middle Income Semi-Redneck
All fine points, Dave. I just don't agree it's an either - or.

I don't think this is a competition of ham vs CB. I don't think HF exists to the exclusion of CB or SSB CB. I don't think it's fair to say, "Why bother with SSB CB when you can get your ham license and go crazy with 2m/70cm". IMHO CB exists on a different planet, maybe even galaxy, universe, or even dimension from ham radio.

Choosing one is not at the exclusion of the other.
If I was buying a CB anyway I can see the benefit of getting one with SSB. But I don't see any point to buying another CB just for it. It is a hobby at that point and amateur radio is so much more flexible. I may have mistook your suggestion as an alternate to GMRS, which is what I meant to say. If I was suggesting to a new 4WD user or group starting from zero I'd just skip CB altogether and build out a GMRS infrastructure. I know this isn't going to happen soon, if ever, since CB and 4WD are one in the same broadly speaking. I think the ExPo crowd and some smaller groups such as TLCA and I believe Rover clubs have embraced ham but the average guy doing weekend runs in your typical Jeep club is still CB and probably CB only.
 

sonoronos

Usually broken down on the side of the road
If I was suggesting to a new 4WD user or group starting from zero I'd just skip CB altogether and build out a GMRS infrastructure. I know this isn't going to happen soon, if ever, since CB and 4WD are one in the same broadly speaking. I think the ExPo crowd and some smaller groups such as TLCA and I believe Rover clubs have embraced ham but the average guy doing weekend runs in your typical Jeep club is still CB and probably CB only.

That's a good point - the location of the original poster might also influence what's available as far communication goes.
 
Last edited:

BigSwede

The Credible Hulk
While my local group uses ham, the group I see in Moab every year uses CB. I have a Midland 75-822 + mag antenna I put in the vehicle whenever CB is needed. Nice not to have to find a permanent mount for a CB that I use a couple times a year.

There is no one answer at this time, main thing is to know your audience.
 

REDONE

[s]hard[/s]MEDIUM Core!
If I was suggesting to a new 4WD user or group starting from zero I'd just skip CB altogether and build out a GMRS infrastructure. I know this isn't going to happen soon, if ever, since CB and 4WD are one in the same broadly speaking. I think the ExPo crowd and some smaller groups such as TLCA and I believe Rover clubs have embraced ham but the average guy doing weekend runs in your typical Jeep club is still CB and probably CB only.

My contention with GMRS is that it costs $70 for the license and gives you a fraction of the access you get with a technicians license that only costs a $10-20 test fee.

I completely agree that adventurers like us should just skip CB and leave that to the foul-mouthed long-haul truckers looking for lot-lizard BJs and meth. I drive from CO to the PNW at least once a year and use to tune my CB rather than listen to the same 5 songs that are popular at the time, and it's just gotten so...incredibly...GROSS. I don't believe the FCC even bothers trying to regulate CB anymore. :(

To give the OP a starting point for learning about amateur radio, it starts by understanding the benefits of FM over AM (CBs are amplitude modulated), and the difference between "energy" (frequency) and "power" (amplitude).

Here's a picture of AM vs FM I borrowed from PBS:
fmamcompare.gif


AM sucks for comms, both voice and data, which is why nobody listens to AM radio anymore (even though some sports and religious channels still operate for some reason). The reason AM sucks is that Amplitude is effected by lots of factors, most applicably for us are distance and obstructions. In order for your receiver to turn that signal into a coherent sound, it pretty much has to be perfect. If the power of the signal is cut in half (the distance between the top of one wave and the bottom of the next), the modulation is cut in half, so either the receiver doesn't recognize that it's a signal, or it comes through as Alvin the Chipmunk mumbling at you.

FM gives far better clarity because it's not as dependent on power. It cares about the distance between peaks, NOT how tall they are. So long as it can see the peaks it will give you a clear sound.

Now for energy, high frequency=high energy, low frequency=low energy, and Energy DOES NOT equal "power". The higher the energy, the more information it can carry for a unit of time. The downside of higher energy is that it's "more fragile" for lack of a better term. It doesn't "bounce" as well and it doesn't "bend" as much. For this reason, the higher the energy, the closer you must be to "line of sight".

Now for a comparison, CB is around 11meters in frequency and limited to 5 watts PEAK power. This doesn't mean you transmit your signal at 5 watts, it means the tallest peaks in your signal are only allowed to be 5 watts tall. Since the signal is amplitude modulated, only a very small fraction of those peaks will reach that 5 watts in power. With a 10 meter amateur radio, you can transmit at 5 watts (you're allowed much more, but for comparison's sake) and it's 5 watts solid, every peak is 5 watts tall. The waves will bend and bounce pretty much the same as 11 meter waves, but with the power to push them out much farther and be received much clearer.

That's just one comparison between ham and CB, out of many, many more that could be made.

I operate two dual band radios (both 70cm/2meter). I have one that is stand alone at 5w @ 144.390MHz with a tablet for APRS, and the other is in the Jeep for trail comms (with 25w peak output). If I was concerned with contacting people outside my group, I'd have a 10 meter rig as well, but where I like to roam, there's no shortage of voice ("phone" in radio speak) repeaters as well as digipeaters for the APRS, so for me it hasn't popped up on my to-do list.
 
Last edited:

DaveInDenver

Middle Income Semi-Redneck
The death of AM has been predicted for 50 years but it never seems to materialize. There are some important reasons AM still exists, in particular to this discussion the use of SSB. What we refer to as AM actually means DSB-FC. That's a fancy term meaning double side band, full carrier.

When you key an AM station a carrier is generated, which is a sine wave at your selected frequency, say 27.000MHz. You modulate this with your voice, say 2.0KHz, and a modulated signal is created that is a sum of those two frequencies. When you measure this an average power will be seen, but the way the FCC wants it done is to average the power of the carrier with no modulation. In that case PEP is equal to total power. When you add a signal that is 100% modulation with both sidebands the PEP will be 4x that carrier PEP, so you'd see 16W PEP.

While this is fairly high fidelity it's highly inefficient. A lot of transmitter power is generating a carrier and with the human voice the two sidebands are effectively mirrors of each other. So if you were to eliminate one sideband and punt the carrier you can put all that energy into transmitting useful information.

Which is exactly what SSB means, technically it's SSB-SC, where you usually see the SSB given as one, e.g. LSB-SC or USB-SC for lower or upper, suppressed carrier. When you key a USB-SC transmitter with nothing modulating it you will see zero power, there's no carrier being transmitted. Which is why the FCC wants 12W PEP measured at 100% modulation. When you do that you will see a similar average power or peak voltage on the antenna as the DSB-FC.

The difference is this transmitter is >95% efficient at using transmitter power for information, e.g. your voice. But to RF there's not difference, mainly how much interference you can create regardless if you have a carrier or not. The PEP determines this, so 12W PEP for SSB and 4W PEP AM with the same person talking is the same potential EMI.

The problem is you need a special receiver that knows how to rebuild the signal by mixing a carrier with the received signal and sending that to the detector. Which is why SSB isn't used much with CB and the point of the earlier posts. It's a chicken and the egg. Without radios to receive SSB it doesn't do any good to transmit it despite that you'll significantly increase your range. With SSB on ham it's not unusual to get a 5W SSB contact of several hundred miles.

With FM you also have a carrier that you modulate with information but the disadvantage is you can't suppress the carrier, you must transmit it for the demodulation to work. So it's inefficient and actually less efficient than AM with a carrier. But the fidelity and interference rejection is must better so it's been adopted readily. But that's why mobile radios are usually 50W, you need it. CB at 4W isn't great but that's partially due to being 11m compared to 2m. A 5W 2m handheld isn't all that great either, but being a shorter wavelength the antenna efficiency is better and you can achieve gain easily. An antenna with gain for CB would have to be more like 18 feet tall or configured with multiple elements, e.g. a beam or yagi.

FWIW, aviation still uses AM radios. Some of that is because it always has but also because it deals with fringes better. FM is static or signal, it doesn't do well at long distances with poor signal-to-noise. AM and SSB are much better in this respect.
 
Last edited:

Forum statistics

Threads
185,529
Messages
2,875,557
Members
224,922
Latest member
Randy Towles
Top