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simple long range comms

4K views 44 replies 12 participants last post by  Clay 
#1 ·
I've been reading post after post asking what the best radio and best band is to use for survival purposes. A lot of you are asking how do I communicate more than a few miles which is the simplex limit of most handhelds, ham or otherwise. Here is the answer - first you will need you tech license, this will take care of you from 6 meter to 23 cm VHF/UHF. What people tend forget is a tech can also operate on the CW portion of 80, 40 and 15 meter HF bands. Worry not - you don't need to learn Morse code. All you need to do is download cwtype and cwget to send and receive code using your computer. For $300.00 you can get a MFJ multi-band 5 watt CW transceiver, you will also need a USB/Serial cw keyer which costs $5.00. For an antenna all you need is a single long wire antenna cut to the middle of the CW portion of each band. Depending on the conditions and which of the three bands you use you will be able to communicate locally 25 - 50 mile on a consistent basis. I know this works because I do i t. You will also be able to work DX stations all over the world. In addition to being practical it's a good place to start for new hams wanting to learn radio and can be fun for the whole family without spending a lot of money.
 
#2 ·
This is a good point. I'll add that you don't even need to spend $300 on a CW rig. A little Googleage for "CW QRP 40m" or something similar should yield results in the sub-$100 range, or even kits for the price of a Baofeng.

Obviously you may lose a bit in terms of flexibility -- cheapest option may be a stand-alone single-frequency 40m transmitter (meaning you'd need a separate receiver), but if you want the option for different bands/frequencies and integrated transimit/receive, you'll pay a bit more. Still mostly affordable, however.

Also, if you have a laptop and portable tx/rx capability, you'd be well set-up to work several digital modes in addition to CW.
 
#4 ·
Yes, people do tend to forget that Techs can use the old Novice allocations on HF, and that is too bad, because this really is useful.

A recap, Technicians do have the use of all VHF and up ham frequencies (all legal ham freqs above 30 MHz) at full legal limit, and people tend to fixate on that. But Techs also can use the old Novice allocations, which allow CW (CW is an abbreviation that has come to mean Morse code in the HF communications world, including with hams) on 80, 40, 15, and 10 meters, and voice on a small segment of 10 meters. Power in these allowed Novice segments can be up to 200 Watts PEP. 200 Watts on CW can easily get you the world on these bands, even without great conditions. Under only average conditions you can count on coast-to-coast coverage using CW and 200 Watts on 40 meters.

Yes, you can use QRP on HF (power levels at 5 Watts or less on HF is considered "QRP", or low power) and get some inexpensive equipment. And QRP can be a fun challenge. But as for reliable communications, QRP can be frustrating beyond direct path distances, meaning distance much beyond the horizon.

Because of this potential frustration I never recommend to a new user a QRP power level radio. Often for the cost of a decent new QRP rig you can pick up a nice full power (typically in the 100 Watt range) used radio. And you can always turn the power down to QRP levels if you want or need to. Better to have the power and not need it than to need it and not have it.

As for not learning Morse and using computers, yes you can do that, but there are pitfalls here. The following is NOT meant to discourage this in any way, only to point out the things people need to be aware of. By all means, use software and CW, just be aware of some of the shortcomings. While I have done Morse by ear since the 1960's I still sometimes let a machine do the work for me.

I have used every Morse reading program I am aware of, including professional level software that costs in the multi thousands of dollars for a license, and compared to humans, CW copying programs make mistakes...often. Why is that?

They must have a decent SNR to be able to hear and decode the CW, and on HF the SNR often fluctuates, meaning that a program might copy great for part of the transmission, and not so great for other parts. With CW, skilled humans can work with low signal levels resulting in SNRs sometimes of only 1 dB, software, operating in real time, often requires 6 to 12 dB to make out the information. And noise/QRM/QRN will impact software copied CW when it might not impact human copied code. So software does OK on clear, reasonably strong, CW, and much less well on weak stuff.

Also, CW is a series of dots and dashes (typically said verbally as "dits" and "dahs" to more approximate the sounds you hear) in specific sequences and ratios. A letter / number / figure is called a character, the dots and dashes within a character are called elements. All basic timing of these are based on the dot (dit) length for a given word rate, the dit is the basic clock unit. So spaces between elements (the blank time between dashes and dots within a character) are one dit long. A dash (dah) is 3 dits long. The pause between characters (letter, numbers, figures) is 3 dits long, or the same time as one dah. The pause between words is 7 dits long.

The point of that description of how CW works is that CW copying software expects that spacing / format with some programmed in variations allowed. But human sent CW can be very variable. People can speed up, slow down, pause, etc, they are not machines. Every time the human sending the code changes things the software trying to copy must adjust, and it often misses a character or two each time it does. So in this respect CW software does relatively well at copying machine sent Morse, but not as good at human cent code.

The problem with all this is that unless you have some level of CW ability yourself you may not be able to tell that the software is in error. If the output of the program looks like gibberish...was that what was sent? Or did the software make a mistake?

And CW is supposed to be a minimalist approach to communications, requiring minimum gear and able to achieve communications under conditions when voice is not usable (CW is usable, when decode by humans, at much lower SNRs, than voice). Adding a computer and software to this increases complexity, points of failure, and power requirements. If you have all that gear and infrastructure then why not use one of the digital modes that is better suited to machine copy? Yeah, you can't do that with a Tech license on HF, but man, they can work well under poor conditions.

T!
 
#5 ·
Yes, people do tend to forget that Techs can use the old Novice allocations on HF, and that is too bad, because this really is useful.
Very true, if you are going to use software to send and receive CW it needs to be configure properly. I really like fldigi for receiving because it has some very advanced cw filters and other features that allows me to decode Morse that I could never do with my ears alone. I use cwtype to transmit and it works perfectly for me. People for get that CW was the first digital mode.
 
#9 ·
No, my software is not configured incorrectly. As I said, software (talking real time application) is prone to making more errors than a human of decent skill. This has been studied, it is not my opinion. When talking about Morse code transcription, skilled humans make errors of one type (typically writing / typing errors, they may have it right in their head, but it does not make it to paper right), machines make errors of another type (interpreting the wrong character or not recognizing a character).

Examples: software cannot differentiate the sweep of a chirp sounder from a dit, software almost always requires a better SNR to detect human sent code than a human does, software cannot "fill in the blanks" when it misses an element due to a burst of noise, software cannot correct for speed changes in human sent code fast enough to NOT to occasionally miss characters. Humans can do all of that.

Speed and timing errors are a real problem for machine translated code. When dealing with machine sent code this is not an issue, but put the old Mk 1 mod 0 wetware behind a straight key and it certainly can be. The software has to monitor a few dits and dahs to set the speed of the code being received. This is required for the code to recognize the basic timing (really good, professional, level software will do that in a buffer, apply the corrected speed to the buffered audio, and present it to the operator without missing a beat, we are not talking about fldigi here). If the code from then on remains on time the software will do fairly well, even excellent, at transcription. Any speed change during the run absolutely requires the software to reevaluate the speed and set a new “dit” length for basic timing. Speed changes in human sent code within or around characters are impossible for the software to track. Lets look at some examples of what I mean by that last one.

The letter Y (- . - -), if a human sending adds just one dit length timing error anywhere in the character many softwares will interpret that as now two letters, T and W, or N and M, or K and T. If the software does not interpret it that way then when the letters T and W are sent with minus one dit widths variation in spacing than they will be misinterpreted as Y. The letters M and E, if run too close together will be interpreted as G. And there are many examples of these kinds of issues, not just one or two.

Each of these human timing errors above can cause the software to reevaluate and adjust timing when not needed, causing further errors.

Under conditions of rapid QSB a human can interpret which character is being sent even when the signal drops below detectability. Software can’t do that.

If your software always works flawlessly then you are not listening to signals at the lower end of detectability. Nothing, human or software, works "flawlessly" on Morse in weak signals, everything and everybody makes mistakes.

But, if you want anecdotal indicators, if software is as good as or better than humans, why don’t “serious” ham contesters use it for contacts? They may use something like Skimmer to see who is on, but they still receive the contacts by ear even when they send by machine. Why does the military, with the deepest pockets for software development, still train intercept operators to copy Morse by ear? Because unfriendly humans still send Morse. Fort Huachuca may have dropped out of the Morse game, but Goodfellow and Corry Station are still in it.


T!
 
#16 ·
I'm thinking that won't work with my 897, do you know what will
A simple audio interface is all that is needed to decode CW (or any other mode fldigi supports). On the back of the 897D is a DATA port, pin 5 is the audio out, and pin 2 is ground. Build an audio cable (you might even be able to find one pre made) that allows you to take that signal into the line in port of your computer sound card.

T!
 
#17 · (Edited)
On my kenwood it's just a USB cable to my computer to connect. Otherwise you might look for a rig that can connect the speaker output to the computer's mic input. With some digital the computer will be able to hear things that you won't be able to. Of course interference will play a roll.

To the other OP's point. You 'could' use a CB Radio that can cover 25-50 miles IF YOU HAVE DIRECT LINE OF SIGHT, even at a couple of watts. Think mountain to mountain top. Reality is that most people don't have that luxury.

But do not cut yourself short, the General class will give you MuCH more options to practice with before SHTF. Also, learn how to make your own antennas. This is important! Otherwise you may burn out your rig that you paid so much for. Those auto-tuners built into the radio can only help so much.
 
#22 ·
Reasonably often when there are 2 or 3 stations in ~100 Hz yes, you can make out enough to have comms. If one is very strong and the others weak, then this will not happen, but if one is not overpowering the others, so you can hear all tones, a skilled CW operator can make out signals with a few tens of Hz difference. You can easily hear the different pitches of the signals present, the thing that takes time to learn is to ignore the other signals that you can hear with the different pitches.

Remember it is not all just about separation of close signals though, the issue of speed changes and timing errors with human sent CW is a real problem for software. A human who sends one character at 5 WPM and the next at 15 can be hard for software to track, since it must have speed lock to translate the CW. And a human can sometimes anticipate what is coming next, and so even though you did not quite hear the whole character you heard enough of it to be pretty sure what the letter / figure was. A machine, in the same situation, will result in trash, or worse yet the wrong thing, because it has to just go with what it heard, not realizing it missed part of the character.

Also, signals with minor transmitter issues are really tough for software to do. Sag/drift/chirp is tough, and excessive key clicks can cause issues with software. These technical issues are something that a human of average CW skill can overcome easily.

T!
 
#24 ·
so, having an 897, and a PC with sound card.
i need cwget, USB keyer (what is that for if i'm not keying)
what else do i need, anyone doing this with an 897
i do have a CAT cable, i can run some program on it, cant recall the progam (its a free one), so it connects fine, and i can control the frequency for example. or should i just get some little qrp rig
 
#27 ·
Don, do you want to transmit and receive CW? Or just receive?

And your 897 will work fine.

Assuming you want to receive only, all possible modes, CW, RTTY, PSK, MFSK, etc, you can do this with a $20 solution off the shelf. Assuming a computer with a sound card input, you need your radio, an audio interface cable, and decode software such as fldigi. This setup will also support transmitting CW with an additional cable and posibly another piece of software, however if you want to transmit those other digital modes a totally different solution is required, something like http://www.westmountainradio.com/product_info.php?products_id=pnp at a minimum.

So, on the assumption of receive only, all modes, or receive now with later addition of CW transmit, and covering only the receive setup:

Start by building or buying a cable to get the audio from your DATA port to the sound card. If you want receive only, or if you want to receive any mode but transmit only CW, the cable I pointed to before ( http://www.westmountainradio.com/product_info.php?products_id=ft817_audio_cbl ) will work. With this you will be able to receive any digital mode you have software for, but that cable does not support transmit.

One end of that cable plugs into the DATA port on your 897, the other end goes to the Line Level Input of your sound card. It all only plugs in one way and that cable assumes 1/8 inch (3.5 mm) line level in, not RCA or Phono jacks.

You will then have to configure whatever decode software you are using to use the audio from your sound card line level input. This is often a two part process, setting things in a Windows control panel and then setting the decode software to recognize which input you want to use. Typically pretty easy and straight forward.

What CW decoding software to use? There is a lot of it out there, from free to thousands of dollars. Probably the best free one is fldigi (http://www.w1hkj.com/ ). This program also allows you to receive and decode a lot of digital modes.

You don't need the software to control the rig and CAT cable unless you want to control the rig via computer. You can manually tune to a signal (in either CW or SSB modes of the radio, it does not matter to the decode software), start fldigi, select CW (or whatever mode you are trying to decode) under the Op Mode menu, select the signal you want to decode on the fldigi waterfall, and start decoding.

That is the basic CW receive / decode operation, you can adjust and optimize things, but that will get you started.

T!
 
#25 ·
you don't need a cat cable or to mess with your data port like FT was blathering about. Just run your audio out of the radio to the sound card. You will want to use Fldigi rather than cwget, it works better and it's free. I use cwtype to send because I am using a usb keyer.
 
#26 ·
Excuse me? Blathering about? I assume you did not actually read what I posted then since you ended up saying the same thing but without specific details?

Look at what I said, I never mentioned a CAT cable. Not.One.Time. I told him specifically which pins on the data port on the back of his radio will bring out fixed level audio so that he could set up a simple audio interface bringing audio to his sound card.

Audio out of the data port into the line level input of the sound card.

On his specific radio the only way to get fixed-level audio (so that the audio level to the sound card does not change as you adjust the radio volume) is from the "data" port. The data port and the CAT ports are not the same thing. On that radio (FT-897D) there are three ways to get audio out to a sound card, the front panel headphone jack, the rear panel aux speaker jack, or the "audio out" in the data port.

The phones and aux jacks are high level audio, amplified and meant for driving speakers, and are a higher voltage level than what is normally used by the line level in of a sound card. They also change level as you adjust the volume control on the front of the rig, generally not desirable for decoder use.

Pin 5 (high) and pin 2 (ground) of the data port provide fixed volume level (not changing with front panel volume control) line level audio well suited to take to the sound card line level input. This is the preferred source to use as audio to the sound card.

As I said in my "blathering" post, you can build the cable yourself, or you can buy one premade, like this (listed as an 817 cable, but read the description, it also works with the 897):
http://www.westmountainradio.com/product_info.php?products_id=ft817_audio_cbl

You got a better way for him to get the audio out of his FT-897D to the line level input of a sound card?

T!
 
#29 ·
I'm thinking TX/RX
I'm in a valley, the folks I want to communicate with are in a valley, about 200 miles, I'm hoping 6M on CW will allow consistent comms for that distance, like I said earlier, I can hardly ever talk to San Francisco area on any band, and for me if propagation allows me to talk anywhere in CA, I usually can't talk far outside of CA, I am central CA right in the middle just inland from the coast (Monterey Bay Area), so my thoughts are considering 6M is pretty good for very local comms (I can always talk inside the city on 6), I'm thinking 6M likely being best bet using CW to talk to SF area consistently since CW will travel farther
Oh, the guy I'm trying to talk to is building a 6M beam, ill be using homemade dipole


Sent from my iPhone using Tapatalk
 
#31 ·
I'm thinking TX/RX

I'm in a valley, the folks I want to communicate with are in a valley, about 200 miles, I'm hoping 6M on CW will allow consistent comms for that distance, like I said earlier, I can hardly ever talk to San Francisco area on any band, and for me if propagation allows me to talk anywhere in CA, I usually can't talk far outside of CA, I am central CA right in the middle just inland from the coast (Monterey Bay Area), so my thoughts are considering 6M is pretty good for very local comms (I can always talk inside the city on 6), I'm thinking 6M likely being best bet using CW to talk to SF area consistently since CW will travel farther

Oh, the guy I'm trying to talk to is building a 6M beam, ill be using homemade dipole
On the surface I would say that it is unlikely to work for you. I love 6M and use it often, and it does get over hills better than higher frequencies, however 200 miles, as a regular thing, on 6 is difficult even if not in a valley. I have done that kind of range when both stations had high gain antennas and real power, but I suspect it won't work for you.

200 miles is a tough range, not far enough for most skywave (but NVIS should do it well), and too far for direct path.

160, 80, or 40 meters should all do what you want, 80 and 40 probably under most conditions. Maybe daytime and night time freqs, something on 160 or 80 at night and 40 during the day.

To transmit CW you could use the system I described and add the USB keyer that IceStationZebra linked to earlier ( https://www.amazon.com/SODIAL-6-5mm...sb cw keyer&tag=vs-outdoors-convert-amazon-20 ) and a program like CWType.

Or you could go a whole different route (hardware wise) using the Rigblaster solution I discussed earlier ( http://www.westmountainradio.com/product_info.php?products_id=pnp ). That would do all the connections needed, audio from the radio to the PC to decode the CW (or any of the other supported modes like RTTY, PSK, MFSK, etc), keyer from the PC to the radio to key CW, and modulated audio from the PC to the radio to support other digital modes. You could probably do it all with fldigi, and no other software, however I never use fldigi to transmit CW (I use a key) so I have never confirmed that would work. At worst you would have to add another piece of software.

T!

(edit) I see that while I was typing Robere' was saying much the same thing.
 
#30 ·
Hi Don, I strongly doubt if 6 Meters will work that way. It may be doable on 6 meters with beams at good height on each end; though, the valley makes it much tougher. The good news is that an NVIS set up on 80 Meters will do very well over the same distance especially at night. 40 meter CW will do as well in the day time. This is a distance that the 60 meter frequencies are meant to cover, to some extent, both night and day. hth
73,
Rob
 
#32 ·
ahh, you think i'm reaching a bit far with 6M huh, i kinda figured
20/40/80 doesnt do that distance for me, like I mentioned before, the waves just dont go there for me
My antenna is home brew inverted V, fan dipole, with 20 and 40m legs only, its peak is at about 32 feet height, i'm located in the valley of Salinas Valley, meaning even deeper into the valley of a valley, like flood plains of the valley, my property/house is surrounded by houses that their foundation is at the level of my roof peak, and my antenna is hoisted only 8 foot above my roof peak, and since it is inverted V fashion, the 40m ends terminate at around 12 to 15 feet above ground (which again is below the basement level of the house behind me).
just for some reason i cannot generally talk inside of CA, or CM/CN regions, DM/DN region is generally really good to me, then FM, i typically can barely hear EL/EM/EN. When I do have good comms inside CA, i usually cant communicate anywhere outside of CM/CN, we've tried 10/12/15/17/20/40/80, my rig wont tune 60 or 160, and only on occasion can we talk on any of those bands, usually 40 when we can, the guy on the other end has much better antenna conditions than I do, and he runs an amp here and there, mine is 100 Watts and Wire, still no luck, he is building a 6M beam or quad right now, I was hoping maybe we could capitalize on that and maybe go CW.
I havent tried any NVIS yet.
I was hoping CW would have a chance at bouncing a few more times and making it that far
I could of course try CW on the other bands, it might work great for 20/40/80
I'll have to see if my rig will do CW on 60, or not, that could be an option too

anyways, I will look into a few of those things a bit more, see if i can get my radio to cooperate as is, or if i need to do something else
I'm still curious, why do I need a keyer, if i'm letting the computer do the keying for me?
 
#33 ·
Hi Don,
An easy experiment would be to put a reflector wire on the ground/ under the dipole you use on 40M. If your dipole runs the length of the house just staple some wires as close as possible to the length of the dipole on to the roof supports in your attic. A couple of wires near the peak on either side ought to have some effect. It may be that with the sun spots on the decline NVIS won't work on 40M. Your next best bet if you can swing the room is on 80 meters. A loaded (shortened) dipole for 80M ought to get you there in the space you have. Get the antenna cut for the portion of the band you will be using. Smaller loaded antennas won't be as broad banded. hth
73,
Rob
 
#34 ·
For 80 I would have to do end-fed, bent
basically, the peak of the dipole is pretty much centered on the house, my 40 legs go just beyond the edges of the house, to do 80 legs, i'd go to the edge, probably the fence on each side of house (about 35foot), then bend to the south for about 25 feet or so, which would be parallel to the ground at about 6 foot height on the top of the fence.
the only other option for dipole would be have a leg pointed about NW, the other leg NE, both going to my back fence which might get 45 feet per leg, then bent inside, run along the back fence line toward each other for the remaining 20 feet or so. the ends would not quite meet, being maybe 20 feet apart. think of a triangle looking down from the sky, with the the middle (few feet) of the top edge removed, the heights at the ends would be higher than my current 40 legs.

oh, for a 'reflector', are you thinking mimic the dipole full length, or just a foot long wire under the eves at each end? 12/14g wire?

Sent from my iPhone using Tapatalk
 
#35 ·
Hi Don,
First, the dipole ends can be bent about a bit, normally you'd want the current lobe (center) up high and straight. Bends the ends in opposite directions if possible. (Z shape) The reflectors ought to be under the antenna as much as possible and nearly as long. A loaded dipole is an option for 80M but it looks like you can go full sized. I am a bit surprised you are not getting NVIS effects on 40M though it is probably the band. I remember when the last cycle got 'better' and some of the engineering guys were talking about the NVIS being back on 40. With the low sunspot numbers it is probably the band. In any case, trying 80M may solve your 200 mile problem.
73,
Rob
 
#38 ·
For the record Don, I have a 40 meter dipole 15 feet up and I regularly have conversations with folks in your area and over in San Francisco. With that antenna I've pretty well covered most of California, Oregon, Arizona, Nevada, Idaho and Washington. I've also worked Reno regularly which is about 70 miles from me.

I'll agree with Armordude. A Signalink usb and FLDIGI is the way to go. It works for CW and you can do a ton of other modes as well.
 
#41 ·
HRD allows computer control of the radio. The DM780 decode suite is integrated.

However computer control is not required to do digital modes or CW decoding. Of course, if you want computer control by all means do it, I just want to clarify, you don't have to use computer control with a program like HRD to do these things.

The next thing is that the CW decoder and several of the other modules in the DM780 suite are not as good as what is found in other software like fldigi. HRD was the stuff...5 years ago. The most current version of the free software has not been updated since 2012 (Simone sold the rights to HRD to another group, who updated everything but made it a "for pay" program, Simone then moved into the realm of SDR software with his outstanding SDR-Console series of softwares).

So you can use something like fldigi or MultiPSK stand alone. The audio to and from the radio, a hard key line to make the CW, and tune the radio by hand.

T!
 
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