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Discussion Starter · #21 ·
Okay no video right now, but busted out the WebSDR and MS paint.

Here's a radio in California, about 1,000 miles from me. Notice the red box: it's blank. It means nothing is being "received" by that California radio on that frequency.


Here I've typed in my message (Blued out) into the FLDigi, and then hit the Transmit button.


Aaaaaand magically in California, that guy receives my Olivia-encoded message. On his/her end it sounds like a bunch of R2D2 noises, but if the laptop is running the correct Olivia encoder, my text will show up on his end, get decoded, and a plain-text version of the message will show up.


***

For context, this is roughly a 3-watt signal being received 1,000 miles away. If the sun does its thing, I can hit the east coast, roughly 2,000+ miles away from me.

Anyway, I'd like to think this setup gives a decent low-cost way to get comms to your people across the country. For local stuff, rock a Baofeng like a normal person.
 

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Sorry to have to lead with this, but this post assumes you’re a licensed Ham user. If you’re not, you can’t run this rig. Rules/Restrictions where I am located might be different for where you are. Know the rules applicable to you, stick to them.

Well I’ve been meaning to post this for a while. Below is a how-to for what I think is a really good choice for a basic minimalist HF comms setup for all of the Be Prepared people out there on the internets.

Before I start, I need to get a few things out of the way. There are a few keywords written above that I’d like to define for our purposes:
  • Minimalist = Small, portable, no overly-technical drama required to set up.
  • Comms = Ability to easily send/receive accurate information to/from a specific 3rd party.
These definitions are important, as they drive the whole theory behind this setup. (More on this later.)

WHAT YOU NEED.
You need some gear. Get this stuff:
  • Rugged laptop (Mine’s a CF19 Toughbook.)
  • Venus DR4020 here.
  • 2x 3.5mm male-to-male audio cables (already come with DR4020.)
  • 12v power supply. I like this one here.
  • Antenna (Here if you want to build your own.)
  • FLDigi download here. (If you're running Windows, get the .exe one.)
  • Beverage of your choice.
That’s it. (Beverage for scale.) I have no affiliations with any vendors here. Bought all this stuff with my own money, and received the usual Wife-Flak, same as everyone else out there.


HOW TO SET UP.
In the “Comms” definition above, I mentioned the word “Easily.” Well, that’s intentional - If something isn't easily implemented, people won't bother to use it. I don't want that to happen here, so this setup is designed to be easy to set up. Here’s how to get it all working:
  • Install FLDigi on the laptop.
  • Plug the laptop HEADPHONES output to the DR4020’s data IN port.
  • Plug the laptop MIC output to the DR4020’s data OUT port.
  • Connect the antenna to the DR4020. (Assuming you’ve already set up the antenna.)
  • Connect your 12v power supply to the DR4020.
  • Turn on laptop, fire up FLDigi.
  • Turn on DR4020.
  • Done. (Remember to configure soundcard options on FLDigi - This is beyond the scope of this how-to, as it'll depend on stuff like Windows Vs Linux, onboard soundcard vs USB dongle, etc.)
No math, no forum posts, no ionosphere or sun cycle technical knowledge needed. No software configurations, drivers, hardware fights, etc. Plug and play. It's simple.

HOW TO USE IT.
Alright so you want to talk to check in with your buddies and see how TEOTWAWKI is going in their neck of the woods. Let’s get started:
  • Power up everything, get FLDigi open, etc.
  • Physically dial the DR4020 to your frequency of choice (limited to 20m or 40m bands.) If the country you’re in has digital restrictions, stick to the appropriate frequencies. (Note: Ignore the frequency on the sceen in FLDigi – it isn’t linked to your radio, and has no effect on your operations. Dial your DR4020 to make the magic happen.)
  • On the FLDigi top menu, click on “Op Mode” and select the digital mode you want to operate on. There’s a bunch of options/modes here, with hours and hours of cool reading and analysis avaialbe for all of them. To skip to it, in my opinion pick an “Olivia” mode.
  • Navigate to the “Blue Box” part of FLDigi. Type your message into the Blue box section the screen, and then click the “TX >|” button in the bottom-right. (There’s more on this later.)
There. You’re done. In theory, your pal (who in theory is tuned to the same frequency and running the appropriate Olivia mode on his/her own setup) will receive your Olivia-encoded message, and send an Olivia-encoded message back to you. FLDigi will capture it, decode it, and spit out the plain text on the screen for you to read.

That’s it. You have a simple, easy, portable setup that allows HF comms. Good luck with TEOTWAWKI and/or zombies.

For Fun:
Here's the setup in action, running a software called WSJTX, using a digital mode called FT8. Left side of the screen shows all of the signals that the laptop/4020 are picking up.


The point to be made is that a laptop + speaker wire + a bagel-sized radio = range of 2000+ miles. I don't have any pics handy of FLDigi/Olivia contacts, but I'll get something put together later that'll show everything in action.

***

That’s it for the practical application part. There’s some fluff posted below detailing the theory behind this build, if anyone cares.

THEORY/COMMENTS

Because I know there will be a bunch of “But ackshually…..” stuff pop up, I’m going to try and head those off here:

Digital? Fight me Millenial, voice is king. Yes, I picked digital on purpose. This is intentional. Digital allows for two very important things:

(1) Keeps things small. Don’t need to worry about handsets or speakers or audio or any other auxiliary bits of gear. Just a couple 3.5mm audio cables and that’s it.

(2) Digital modes allow “Comms” at low power levels/long distances.

#2 is critical. Again, my definition of Comms is having the ability to easily send/receive information between specific 3rd parties (ie. Your pals.) From a technical standpoint, voice modes (at low power) suck for that. I won’t get into the nerd stuff, but digital modes smack the crap out of voice in a ‘Distance vs Power’ comparison. It’s essentially why a 1-watt Morse code rig can compete with (and often do better) than 100-watt voice rigs in terms of long distance comms. (Yes, Morse is the OG digital mode.)

So if you want to make consistent, deliberate comms with specific people, to relay specific information, using a small (read: low-watt) rig, Digital is king. If you want to voice-chat with 80 year olds about your various aches and pains, this is definitely not the rig for that.

Just learn Morse Code. Sure. But when Digital modes rival or exceed CW in weak signal environments, why? (Reference here.) Everyone these days can write a text message or an email. That’s why this rig uses a laptop interface: You can get your non-prepper kid sister on the laptop, and she will intuitively understand what to do. You can’t easily do that with a Mountain Topper and a notepad. (There’s that pesky “easily” word popping up again.)

Well you can’t scan/listen to voice with this setup. It sucks. True, no classical voice or voice scanning. But, back to my definition of Comms: “The ability to easily send/receive information to specific 3rd parties.” Keywords here are Specific Parties. What this rig does is allow a person the ability to send/receive information to/from specific people. (Ham world generally calls this a “Net”.) In theory, all the appropriate people involved will have a shared comms plan, detailing times/frequencies that people will check in, protocols, etc. As long as everyone is dialed in to the right frequencies at the right times, you’ll have a very high chance of making contact.

What this means is that a person needs to have all of this stuff in place prior to the world ending. Same with your pals/buddies. Get a plan in place so that everyone knows what to do if you have to start using the radio.

What it doesn't involve is scanning the airwaves for stuff. The intention here is deliberate comms between specified users. You know, like calling mom.

Toughbook? Really? It’s maybe overkill, and a guy could get by with a regular laptop. However, because this rig is “Portable”, I’m assuming that the user is going to throw the gear into a pack or a truck, transport it somewhere, and get some work done. Electronics are no good if they won’t work. Rugged laptops are a hedge against Murphy.

Side-benefit: the CF19 has an onboard soundcard – No need for external USB soundcards/dongles. Just plug your 3.5mm cables in, and done. Pro-tip: colour-code your cables.

DR4020 is commie crap. Maybe. But, it’s the simplest digital rig I’ve found. No usb sound cards, no hamlib or Flrig or Omnirig CAT-Control troubleshooting, no software settings or tweaks involved, nothing. Literally plug in your 3.5mm connections, and that’s it. Nothing else required. If you colour-code the connections, it’s the easiest thing to set up. I can talk my kid sister through setting it up over the phone without breaking a sweat. Simple is good, and this little DR4020 rig is dead-nuts simple (Not sure how rugged it is, but it’s been holding steady so far. Get a Pelican case if you're worried.)

Olivia sucks and is too slow. That’s, like, your opinion, man. I’m not going to get into a huge technical analysis here. (Go read NBEMS theory for background if you want.) In summary, Olivia 8/500 gets decoded consistently, pretty much every single time, by all users and regardless of band conditions. Copy rates are easily 80%+ no matter what. For intentionally sharing accurate information with specific parties over HF, the Olivia modes nail it. It’s not perfect, but for my purposes it fills the role it’s supposed to: get info to people every time, without having to pray to sun cycle gods or other such nonsense.

I'm sure I missed something, but I think the above gives pretty good context into the purpose of this build. So that's all I have for now.
Brilliant. The only other thought is to sub the much smaller Toughpad FZ-M1 for your Toughbook for ultra portability.
 

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Simple vs minimalist

Audio equipment Gas Electronic device Machine Electronic instrument

HW-7 - simple. Not really small.
(tr)uSDX - minimalist, 5 bands, supports all digital modes and SSB/CW and listening to SW broadcasts - to me very important. AM/CW/SSB/digi and covers 60M, a big deal for me here in Alaska.

The modem, has CW with decoder and can be used with a keyboard. Does RTTY, PSK31 - keyboard to keyboard.
Very small, runs from 2 common AA cells. You can use a paddle instead of a keyboard.
YMMV.
****

Ham Radio Digital Modem (PSK/RTTY/CW) - YouTube shows the size of the modem. I use the NEU-PSK modem.

Once I get my (tr)uSDX laced into my PSK modem, I'll post a separate thread.
 

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Discussion Starter · #29 ·
The radio itself is roughly $150 (It comes with the 3.5mm cables and a USB soundcard.). A used ebay CF19 is anywhere from $80 to $300+. FLDigi software is free.

If you have a laptop already and want to substitute that, the cost is basically just the cost of the radio.

What is the rough cost of this set up?
 

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THANK YOU for putting this together. Question: I have a place in the back woods of South East Oklahoma without internet or phone. Would this system comunicate with my texas place 300 or so miles? I know a bit about a lot of stuff but coms isn't one of them; )
 

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Discussion Starter · #31 ·
I really, really, want to give you a definitive answer here, but I'll have to go with the "It depends" answer.

In theory, it should work without a problem. However, it will really depend heavily on the antenna setup of the sending station, and the antenna setup of the receiving station. If you set up an NVIS antenna in OK, and have a decent antenna setup in TX, then TX will probably pick up OK's signals. Without knowing your antenna setups and details, I can only just kind guess.
It'll also depend a bit on the time of day - Speaking very generally, during the day you'll have better luck on 40m, and night on 80m.

With low power stuff, you want a really well-tuned antenna, and elevation.

Again, there's smarter guys here on this site than me who can maybe offer better advice. @PSYOP Soldier @Lagnar

THANK YOU for putting this together. Question: I have a place in the back woods of South East Oklahoma without internet or phone. Would this system comunicate with my texas place 300 or so miles? I know a bit about a lot of stuff but coms isn't one of them; )
 

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Antenna and terrain and what time. I'm getting ready for the test this weekend so going over and over all the questions. Antenna terrain and time. Dawn is the best. Daytime not as good. Look at different antenna. Dipole is probably the easiest to build setup. And You’ll need to set it up in the right direction. Probably need a balun. I've got a 10 meter between 2 trees. Lots to learn
 

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I really, really, want to give you a definitive answer here, but I'll have to go with the "It depends" answer.

In theory, it should work without a problem. However, it will really depend heavily on the antenna setup of the sending station, and the antenna setup of the receiving station. If you set up an NVIS antenna in OK, and have a decent antenna setup in TX, then TX will probably pick up OK's signals. Without knowing your antenna setups and details, I can only just kind guess.
It'll also depend a bit on the time of day - Speaking very generally, during the day you'll have better luck on 40m, and night on 80m.

With low power stuff, you want a really well-tuned antenna, and elevation.

Again, there's smarter guys here on this site than me who can maybe offer better advice. @PSYOP Soldier @Lagnar
Thanks again for the info. I do have some elevation in Oklahoma. We will see: )
 
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