Started by gridner, September 01, 2012, 10:11:50 PM

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Right now, the only radio I own is a Kenwood TH-F6A, which operates on 2M, 220 and 440 MHz, which is fine if you're around repeaters, but I wonder about its utility in a real disaster.  Is there a "quick" way to determine what repeaters are still operational, without knowing the frequencies of the repeaters in the area you're in?  Or will I be forced to put my radio on scan and listen for hours, possibly longer, for someone to say hello?  Is a VHF radio even a viable option in TEOTWAWKI, except for same line of sight communications for distances I could achieve with a couple of cheap FRS/GMRS radios?  Any insights more experienced HAMs could provide would be appreciated (and yes, I already know about NVIS propagation).


Short answer:  no.

Repeaters do not broadcast any telemetry such as would tattle on their availability -- typically, repeaters sit quiet until used.  In the day of PL tones, even if you know the frequencies, that may not be sufficient to activate the repeater in a way that would then indicate that it's online and available.

This is why it's crucial to have situational awareness in your area and to have LOTS AND LOTS of repeaters programmed in advance.  On my HT and mobiles, I have about 100 channels in use, and when I'm outside of my home area, I can usually find at least a handful of frequencies that are in use in other areas, either with the same PL tone or none at all, such that I can make one squawk.

Repeaters aren't like APRS stations where there's a periodic beaconing.  If it's alive but no one's using it, you will not know that it's there.

Hope this helps.


One of the things that should be in your prep kit and/or vehicle is a repeater directory book. While it's not perfect, it'll give you lots of info on repeaters, including their tone codes.  After a disaster, some repeaters will go offline without power.  Some will remain functional for a few hours to a few days with battery backup or generator power.  After a week w/o power though, many repeaters will simply not be available unless they have a good solar backup for batteries.  Even then, their output may be reduced or sporadic.


Dont know where you live but the U.S. has a repeater directory you can buy in book form or on a cdrom for your computer. Where ever you are you could look up in the book and see repeaters around your local area. THere are also iPad and  iphone apps that do the same and use your gps location to show you a map of area repeaters.

The books are put out each year. Just google repeater directory.

VHF would be good for local talk on a handheld even without a repeater. Try putting a yagi on top of a tower and use that and you will get better range.


You VHF/UHF HT is also great for passively gathering intel through listening.  Unfortunately, many small police departments and etc. are using P25 - which is a digital mode instead of clear voice.  However, many of the OTHER people in your immediate area are probably still on normal FM voice.  By 'normal' I mean , some fire, ambulance, power company, Department of Transportation, private security, taxis (great intel in a metro area), Burger King!!! and etc.  These are primary sources for information on what is happening, because they are often first on the scene. Even if they are secondary sources when they ask for information about 'what just happened?" it's FAR better than the controlled media. Power goes out? The power company crews are usually the first in action, mass casualties?  Your ambulance and local hospitals. Cell phones carry some of this, if they are working - and they use a special CODEC and in some cases encryption, which - beside the legalisms - puts them generally out of reach.

A good place to start looking for area frequencies is on-line.  'Scanner frequencies' and your city/county should get you started.  PROGRAM the frequencies in immediately.  Paper back-up of your frequency list is a very good idea.   When you are doing something else, let the scanner run int he back ground until you develop a 'feel' for what is available and normal.

de RadioRay ..._ ._

"When we cannot do the good we would, we must be ready to do the good we can."  ~ Matthew Henry


During Sandy, most of the repeaters in the area remained operational.

White Tiger

Was the "old" traffic system set up in a way that used each radio as a "node"? If so,!why did it change?

If not, couldn't you send a digital message along from radio to radio until it reached the appropriate destination?

I'm sure I'm showing my ignorance here. - but it is a question I'm interested in and have spent a lot of time discussing privately regarding TEOTWAWKI . It seems like the digital modes via HF/VHF/UHF offer quite a bit of stealth EMCOMM promise!?
If you're looking for me, you're probably looking in the wrong place.


QuoteIt seems like the digital modes via HF/VHF/UHF offer quite a bit of stealth EMCOMM promise!?

Digital modes IMHO introduce a level of complexity that is not practical in TEOTWAWKI. For managed emergencies with various agencies, certainly, that's when it does great. However "TEOTWAWKI" means everything has gone to sh-t. In that case, digital will be out. The only modes left will be SSB, FM and CW. there would be very few digital stations operating, not for long anyway. Wait a few weeks and the only thing you'll hear will be low-current CW rigs. I know, I'm repeating myself, but it is a logical conclusion. Personally, I skip the complex ephemeral gear and go for simplicity first. CW is my go-to mode, though my KX3 is great for listening to SW. My MTR is my bug-out-bag queen. The UV-5Rs will keep me updated on local happenings.. And that's it. Any extra gear is superfluous and I couldn't carry it anyway if need be. Everything will work off AA cells, which I can recharge with my little solar panel. If I was going digital, I might be lucky to find one other guy to talk to in TEOTWAWKI... Before my big heavy battery dies that is... No disrespect to digital guys here, those modes are great when supported by some kind of infrastructure. Otherwise, forget it.


White Tiger

Unless of course you're building a solar charging station and have set up a network for coordination of a team or group. My HT's operate off of "AA" batteries. My HF and VHF/UHF rigs operate off a battery that is charged by the solar panels. The digital modes "sip" juice. It's why I believe it has some merit.

It seems to me - and unless I greatly misunderstood a great many conversations on the topic with a bras pounding friend - if you know how to pass a message to a friend, now, via HF of VHF - you should still reach those same groups after TEOTWAWKI?

I will not deny that your CW will be king (eventually), but as I have been giving this more thought - how many amateur operators are really capable of CW, maybe a third of all of HAM's in this country? Thats less than 300,000 (at best), spread across a giant swath of land.

How many of them have been prepping, a quarter to maybe a half of that number? Thats 75,000 to 150,000 people - across a HUGE landmass.

I have heard many military folks tell me - never become a refugee - build a network of people, then support one another. As I recall, the French Underground in WWII were made up of some strange bedfellows, united by a common cause. It worked because they relied on one another - and only trusted those they knew. In that way, we humans are similar to wolves, we're pack animals. The TRUE strengths of the pack you build will help you survive whatever may come. It's what made us a more efficient hunter - the ability to use superior communication skills and operate together. Not coincidentally, when a wolf is banished from the pack, it starves. The term "lone wolf" is meant to be a bit of a cautionary tale. We will need whatever mode survives - and I'm betting that the ease of digital will give it some benefit and the low power will rival CW. There may be a mad rush to learn CW..."One Second After"...but it will take time and access...

Sent from my iPad using Tapatalk HD
If you're looking for me, you're probably looking in the wrong place.


Sure, I agree.. "The ease of digital," I am not so sure about. Digital isn't that easy. Neither is learning code, I know. The problem is the complexity of the set-up. Tough I have seen tiny PSK-31 rigs, and I think in that regard they are the answer. Someone needs to make a small 5W PSK radio with a small LCD and rugged small keyboard.. Notice I said "small" three time  ;) The form factor could be like a small tablet with a solar panel on the back..



Quote from: gil on October 20, 2013, 12:05:51 PM
Sure, I agree.. "The ease of digital," I am not so sure about. Digital isn't that easy. Neither is learning code, I know. The problem is the complexity of the set-up. Tough I have seen tiny PSK-31 rigs, and I think in that regard they are the answer. Someone needs to make a small 5W PSK radio with a small LCD and rugged small keyboard.. Notice I said "small" three time  ;) The form factor could be like a small tablet with a solar panel on the back..

You mean something like this?

I agree that you are probably more likely to find someone who knows CW than you are to find someone who has a digital-capable rig...and far more likely than finding someone using a rig capable of the same digital mode and frequencies that you are using. If you are creating your own network of friends, then digital can definitely have a place. I just wouldn't rely on it for communicating with the outside world.

Sent from my Transformer Prime TF201 using Tapatalk 4


QuoteYou mean something like this?

Nothing like it. This toy is an FRS radio, good only for a couple miles...

When all else fails, simplicity is the key. Simple devices are the only ones that will work. If you can't repair it using a hot nail pulled from a campfire as a soldering iron, it won't work for long. I don't know how else I can explain this... Computers are not simple devices. They are very fragile and use a lot of electric power. Even in the best of conditions they are unreliable. That's why I am so adamant about Morse code. Because we need to transfer decoding abilities from computers to out own brains! Why? Because voice modes are inefficient. CW IS A DIGITAL MODE. It is just decodable by our brain...

I realize it's not easy to learn code. Anything really worth the effort usually isn't easy. We tend to palliate our lazyness with more gear. It's natural, but it only works when everything is going well. Modern gadgets and comfort goes against ourselves. We lose abilities, physical and mental because we use technological crutches. Sure, we need some technology. After all we use radios. The kind of technologies we need are sinple ones. Prepping should only include the simplest of technologies and avoid the complex ones like the plague, i.e. computers. I have a scientific solar calculator (bought to review for Ham licenses) and that is the only computing device I am keeping in an EMP-proof box. My computers are disposable items. Simple is better, more reliable.

Another primary concern is weight. If you guys think you're going to ride out TEOTWAWKI in the comfort of your own homes, you're in for a big disappointment. Unless you have a well thought-out retreat with lots of armed friends... You're not going to ride away in your air-conditioned SUV either. You might end-up carrying your stuff on your back. How's that 5Lbs laptop feeling now? I know, I know, we're not prepping only for TEOTWAWKI, maybe just a hurricane, in which case all you wiz-bang digital radio gear is going to do great. But my little CW rigs are going to do great too, in either case!

Also about VHF. What the Chinese have allowed us to do with their cheap handhelds is to have redundancy. At $30, you can buy a few and give them to your friends and family. I have two, waiting for a third, on top of my Yaesu. Beating complexity by adding more of the same item is only possible with small and light gear however.

Sorry, I get all hot and bothered about the subject, but hear me out, because I am right! You want the gadgets, great. Have a "B" plan is all I'm suggesting. Prepare for the worst, not the better. You don't necessarily need CW, but have a simple SSB radio then, like an MFJ 9420 or something similar; something light with low current draw. I love the ability to send email via Winlink, but I don't count on it.

Keep it simple.



Quote from: gil on October 20, 2013, 01:19:12 PM
Sorry, I get all hot and bothered about the subject, but hear me out, because I am right!
You may be right for your scenario, but you are not right for mine.  I will not ever be bugging out on foot with a backpack - age and physical limitations have already irrevocably decided that.  My wife and I "bugged out" 11 years ago when we moved to this more or less rural location.  If I get overrun by Zombies, than I am dead, that's all there is to it.  Some situations are simply not survivable no matter what you do.

I truly believe you underestimate the utility of digital gear.  Sure you can pass sitreps or shopping lists or body counts via CW, but try sending a PDF copy of a maintenance manual via CW.   PSK is absolutely the wrong mode to be considering for SHTF digital work - it has the same file limitations that CW has, as do MFSK, Olivia and the others.  The digital modes White Tiger's mentor is advocating (Winmor, Pactor) have the ability to send file attachments over the air - pdf manuals, jpeg images, spreadsheets, executable files - anything you can attach to a normal email can be sent over the air.  That may not mean anything to you in your hidden camp site, but it means a whole lot to me if it means I can get information on getting my closest neighbor's tractor running again.

One early afternoon a few years ago I fired up my Pactor station here in southwest Washington state and linked to a friend's unattended station in Maryland on 20 meters while he was at work.  After the usual automated handshaking my station downloaded a neat jpeg digital photo of his new sailboat he had posted for me before leaving for work.  Conditions were good, we had a solid link and the file transfer took less than 10 minutes.  The subject of that photo isn't important, what is important is the ability to transfer a file from coast to coast with no infrastructure other than our own equipment.

I was using my Icom 703+, 10 watts max output and my friend was using a surplus military rig of some sort.  His maximum power was 20 watts but he normally kept it throttled back to about 10, which is about where it was when I retrieved the photo.  I was running my whole station - including little laptop computer - on a battery operated inverter.  My friend routinely set his station up on a picnic table at work to play during lunchtime.  Carry it on his back?  No, but there are plenty of us who can't do the backpack bugout thing.

Making a system like this work involves the same planning and preparation that establishing your CW network requires.  You and the others emphasize establishing your CW contact list before it is needed.  The same thing is true of a digital network - you have to know the other station is there and you have to know the capabilities of the other operators.  If you have a digital friend on the other side of the country who is a medical doctor, maybe his knowledge could come in handy in a nasty situation.  The time zone difference is less of a problem if you have an agreed upon schedule for monitoring for incoming calls.  You can leave him a message with your questions while he is sleeping and pick up the response later.  Ok, not as good as calling his cell phone but probably better than trying to pull something out of the old reference book on your shelf.

I agree that CW buys you simplicity and light weight.  However, CW requires you to give up the ability to make asynchronous contact (Winmor/Pactor has no need for simultaneous operator on duty at each end) as well as the ability for error-free transmission of information.  Digital duty cycles tend to be very brief, which minimizes energy consumption.  Even if my rig is running at 50 watts, how much energy is used to keep it on the air for 10 minutes, most of which is receive only?  Not much.

Your scenario may be right for you, but it is not for me.  There is absolutely no way my physical limitations will allow me to bug out on foot, so why deprive myself of tools that are very useful during periods when normal communications are down?  My long term SHTF plans involve banding together with my neighbors for mutual benefit, that's just my reality.  Your reality is different.



It's probably no surprise that I agree with Gil on the CW vs. Digital debate for the same reasons he's already stated, but there's another reason that actually may have more bearing. It may sound blasphemous saying this here on the Radio Preppers forum but in a true SHTF, total infrastructure loss, no rule of law scenario, communication via radio will be way, way, WAY down on my priority list whether it be CW, digital, phone, HF or VHF. My priorities each day will consist of immediate security, shelter, water and food. My next priorities will be to try to secure the previously mentioned priorities into the immediate future measured in days and maybe the coming weeks. Time, effort, energy and resources will be a very precious commodity, if I have any left over after securing my immediate priorities, I may have an opportunity to devote some time and resources to radio. If that's the case then I want ultra efficiency and dirt simplicity....... in other words I want CW.
"Those who would give up essential liberty to purchase temporary safety, deserve neither liberty nor safety" - Benjamin Franklin



I understand Wally, there are exceptions. I am all set for Winlink and have successfully sent emails with my KX3 using 5W. I would try to use it as long as possible. If I had to leave, I might hide that gear and hope for a remote chance to find it later when things get better, if they do. Powering a transceiver, interface and computer full time unless you have a good solar setup isn't practical. Maybe a raspberry-Pi or something similar, with a KX3, that might be possible with enough solar panels. The 703 burns from 450mA to 1.2A on receive, and that is a lot. Add the interface and computer, that's a lot of power. There are examples of digital modes used in war-time to relay information to foreign press, but those stations still had power..

If you can't physically bug out, then that's that. Fortunately you are in a rural area. As to CW, or any other mode, I would hope to hear from friends, but wouldn't count on that either.  I think it would be important to find the few people still on the air then, even getting information from a different continent. If I didn't believe in the multiple modes my KX3 has I would sell it and go CW only. I know that isn't the right choice. I also know it is a great skill to have.

I know what digital modes can do. I am not underestimating them or disliking them. I do think however that many Hams underestimate the necessary infrastructure needed to maintain a digital station. It is also natural for people to underestimate how bad things can get..

I am all for digital whenever possible, but for those who can travel on foot, not the only option they should count on.