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If folks are gonna do shit like fake callsigns for KF bulletin broadcasts, doing it outside the ham bands is probably a better idea. There's lots of hams out there with mall cop personality disorder who'll get upset about people abusing their bands and waste retired sperg energy on trying to fox hunt or write stupid letters to the FCC.
If folks are gonna do shit like fake callsigns for KF bulletin broadcasts, doing it outside the ham bands is probably a better idea. There's lots of hams out there with mall cop personality disorder who'll get upset about people abusing their bands and waste retired sperg energy on trying to fox hunt or write stupid letters to the FCC.
My thoughts are that boomers are more likely to go after the easier targets of the 1+ kW jammers on 7200 with static antennas.
I think a lot of these operations are likely to fly under the radar if they are kept to modest power and done infrequently from different locations each time, I think 888's 50W is the highest power I've seen. I think the biggest issue is interfering with others, so if they take care not to interfere the mall cops are unlikely to put much effort into it. Hell most of them probably don't even know what JS8CALL is and have no idea how to to even get the callsign.
Great video on why we use 50 Ohm impedence for transmission line.
tldw a compromise between the lowest losses and highest power capability (you should still watch the video though), and the geometric mean between 30 ohms and 77 ohms
A question for the HAM Radio autists more invested into it than me: how practical would HAM Radio be in Day of the Dead ('85)? They mention how they can't pick up anybody still alive through radio within their range (state of Florida.) but could reach D.C. through a relay in the past when survivors where more plentiful. Is that accurate? I hear about how users can ping each other through radio from distances as far as opposite sides of the world with minimal power but yet that is never brought up in the film.
A question for the HAM Radio autists more invested into it than me: how practical would HAM Radio be in Day of the Dead ('85)? They mention how they can't pick up anybody still alive through radio within their range (state of Florida.) but could reach D.C. through a relay in the past when survivors where more plentiful. Is that accurate? I hear about how users can ping each other through radio from distances as far as opposite sides of the world with minimal power but yet that is never brought up in the film.
I don't know that one in particular but Hollywood does very funny stuff when it comes to portraying radio in movies. Either as magical devices with infinite range, usually never connected to anything or as something that craps out pointlessly for the plot. Real radio communication has many nuances that make it difficult to portray accurately.
An important distinction is line of sight vs beyond line of sight communication.
The most common question asked by anyone who is new to radio, especially the pre,pper type audience is "how far can I talk with this?" when they've picked up their first Baofeng or other handheld for the first time.
The answer is line of sight. With a handheld radio like a Baofeng, it's opperating on the segments of the radio frequency spectrum called VHF and UHF. These two bands operate on line of sight which means exactly as the name suggests. Signals transmitted on these segments mostly travel in a straight line from the transmitter to receiver.
If we are standing on top of a mountain, what we see in front of us is how far our signal will go. If we're on the ground what we see in front of us, and a little bit more or less, is where we can reach and who we can talk to.
If we are using something that operates on line of sight the only way for us to extend our reach is using an intermediary, like a repeater. The simplest analog repeater is one that takes the audio from our signal and retransmits it.
There isn't really a nation wide network of repeaters. There are some state level ones like Florida's SARnet but not one that spans coast to coast or even region to region.
The only way to communicate with someone beyond line of sight without any intermediaries is HF radio. HF radio is unique because the properties of signals in thiss segment (3 - 30 MHz) have the ability to refract off of the ionosphere. The ionosphere is a layer of charged particles in the upper atmosphere that act likes a mirror to our signal.
You can think of our signal on the HF bands like a stone skipping across a lake
The HF spectrum itself is divided into different bands which are called by their names in wavelengths. Each band has it's own properties in exactly how the ionosphere carries it.
Like 20 or 40 meters for example. 20 meters (14 MHz to 14.350 MHz) has different properties and band conditions when compared to something like 40 meters (7.0-7.3 MHz). The sun literally charges the ionosphere and each band represents a different layer height of where our "mirror" is.
With the right frequency selection your range is virtually unlimited. You can talk to someone anywhere in the world given the right band.
You might ask if that's the case why doesn't every radio use the HF bands?
One of the drawbacks to HF radio is the footprint required for an antenna,
The length and size of an antenna directly corresponds to it's wavelength. When most people think of an antenna they think of something like this:
Underneath the plastic here there is a metal coil or wire that is physically 1/2 of the wavelength long
This is called a dipole antenna. At 2.4 GHz, the frequency used for WiFi, our wavelength is 0.12 meters. These little plastic stub antennas for 2.4 GHz you might have seen on a router or computer are something called half-wave dipoles with a conductive element totalling 0.06 meters (2 inches) to make it resonant on 2.4 GHz
At 14 MHz, the 20 meter HF band, our wavelength is 20 metres (65 ft), and a half-wavelength is 10 meters or 32.5 ft. This is why you don't see handheld radios with infinite range like movies depict
To make a antenna resonant on HF that we can use with our radio, we need something that is either physically or electrically as long as our desired frequency we wnat to work. Which means our antenna usually looks something like this.:
A length of wire cut to the desired frequency or frequencies we want to work laid out in different configurations at a height that also has to be 1/2 of the wavelength
The most useful tool for off-grid communications is HF. Knowing the basics of HF antennas and propagation will literally give you the ability to communicate across the world to anyone, anywhere, at any time, and is far more useful then having a Baofeng and what not.
Just thinking out loud here... this might be a dumb question, but if I were to get my amateur license, I could transmit on the 40m band (among others), but I'd like the ability to receive 20m (amateurs aren't permitted to transmit on 20m where I am).
Would it be worthwhile (or even possible) to configure a hypothetical 10m long antenna for both 1/2 wave reception on 20m and 1/4 wave transmission on 40m? I know it sounds obvious, but sometimes something that sounds obvious is anything but.
Also, I know it's a meme and they've been ruined by utter retards, but would a Baofeng be OK as a starter radio for VHF/UHF stuff on the 2m and 70cm bands? I don't fancy the idea of dropping thousands on all this RF gear and then not getting much use out of it.
ust thinking out loud here... this might be a dumb question, but if I were to get my amateur license, I could transmit on the 40m band (among others), but I'd like the ability to receive 20m (amateurs aren't permitted to transmit on 20m where I am). Would it be worthwhile (or even possible) to configure a hypothetical 10m long antenna for both 1/2 wave reception and 1/4 wave transmission? Obviously not at the same time.
A 10 meter long antenna is simultaneuosly a quarter wave on 40 and half wave on 20 meters. But the resonance of an antenna matters far more for transmission than it does reception.
Even if you had a 40 meter half wave dipole totaling 20 meters with both of the legs, it should be able to pick up stuff on 20 with no problem. There might be some minor losses but those are negligible. What's going to matter more (for both DX reception and transmission) is height than anything. Up higher the better.
Reception is noise limited and Your main enemy when it comes to receiving on HF is the noise level around you. You could probably pick up some of the 20 meter band, or even 40 meters with just 2 meters of wire, like those "reel" antennas used for short wave listening if you are in a relatively RF quiet place and were outdoors.
If you want to transmit on all of those bands with one antenna, what you might want in this case is something like an end fed half wave which by design is a multiband antenna and basically what you are describing.
An end fed half wave is a length of wire that is cut for the half of the longest frequency it's designed to operate on fed into a 49:1 transformer that can be resonant on a wide array of bands versus something like a dipole.
20 meters (65 ft) of wire fed into a 49:1 transformer will give you the 40 (our longest), 20, 15 and 10. Al,SO 30, and 17 with a tuner.
A 110 microhenry coil, which is just magnet wire wrapped around something like a 15 cm PVC pipe at the end will give you all of those and 80 meters if you ever want that later. But that part is optional.
You will need a small counterpoise, like 1 meter of wire running as the ground, but most of the time you can get away with just using your coax as the counterpoise in 80% of setups.
Also, I know it's a meme and they've been ruined by utter retards, but would a Baofeng be OK as a starter radio for VHF/UHF stuff on the 2m and 70cm bands?
Yes, they are perfectly fine starter handhelds for 2 meters & 70 cm. What I would recommend instead over a Baofeng UV-5R these days though is a TYT TH-UV88 or UV-K5. Both have the exact same price point. The UV-K5 can be modded with all sorts of crazy stuff with custom firmware and has USB-C charging
I'm not a particular fan of EFHW antennas. Yes you avoid needing a tuner for harmonics, but the ununs have quite high insertion loss 3db or so) and perform badly as SWL antennas due to impedance being extremely low off bands.
I'm more partial to the non resonant type, particularly via a remote tuner. A manual antenna tuner will make it equally good at transmitting as it as as a general purpose receiving antenna. Overall efficiency will be the same or better than the EFHW depending on the feedline. Out in the bush you can hook the wire direct to the tuner, that way efficiency is very high.
Here's a few hints for operating on Single Sideband voice,
In short, Single Sideband (SSB/USB/LSB) is a variant of AM (Amplitude Modulation) aimed at improving energy efficiency, reducing bandwidth usage and the power required to make a contact. Careful setting up of your transceiver and proper procedure can improve this even further. Thankfully its all rather simple!
General Points
Your voice.
To get the best out of SSB, you must speak clearly, at a reasonable volume. Mumbling, whispering, umm ahh etc makes you harder to copy especially in situations of interference or when you are a working weak signals.
Make use of your radio's inbuilt features.
Most modern sets include things like equalisers and compressors, these things can make a dramatic difference in the ability of others to copy you in the noise!
On the receive end, most will have noise reduction, adjustable filters, noise blankers and so on. Read the manual and familiarise yourself with these functions! You have already paid for them, make use of them.
Clear communication
avoid the temptation to be tacticool, copying badly militaryesque nonsense you have heard in movies. Speak as plainly and clearly as you can, again the aim is to get the information across not pretend you are a special operator sped lid.
Configuring your Transceiver
Some transceivers will allow more adjustment than others. As an example I will list general steps, these will work very straightforwardly with the common Icom, Yaesu, Elecraft and Kenwood transceivers. Others like Xiegus have preset compressors and so on and some very simple radios wont have much adjustment at all. You'll have to interpret this to your specific set.
Transmit
The objective is to get the most power from your radio without sounding like a chipmunk or splattering everywhere.
First thing to do is to locate your radio's ALC meter. This tells you how hard the amplifier is being driven.
If your radio has a transmit equaliser, you can adjust this to suit your voice. SSB works best with treble and mid frequencies, bass is generally a waste of power. Icom radios have a simple BASS/TREBLE adjustment. If you have a bass voice add 1-2 of treble and -1 to bass as a starting setting. Yaesu can be more complex, refer to the manual. Don't go too crazy, you will sound like you huffed helium.
Make sure your compressor is OFF if your radio has one to start.
Set your MIC GAIN so that when you speak you get about 50% reading on the ALC meter at the peaks of your voice.
Then turn on the COMPRESSOR, adjust this so you get about a 95% reading on your ALC meter.
Thats it. You should have nice punch audio, maximum average power and not sound like a try hard Italian DX'er.
Receive
For general SSB receiving, setting your filter to 200hz-2600hz will work well. In more crowded conditions 300-2400hz can help improve intelligibility. 400-2200hz is the most extreme while letting you understand what is being said if you have more interference.
If you combine the filter with noise reduction it can really aid communication as well as making the band noise less tiring.
The Noise blanker can be used to reduce certain types of pulsing noise like powerline noise or car ignitions.
One day I hope to see Radio Autoencoder (RADAE) in standard use or even apart of modern rigs. It's developed by the same guy who made codec2 and is a machine learning codec for voice over HF and with RADAE v2 it can work down to -3 dB in a 860 Hz channel. I have seen people make voice contacts on it with as little as 5 watts of power across the Atlantic
One day I hope to see Radio Autoencoder (RADAE) in standard use or even apart of modern rigs. It's developed by the same guy who made codec2 and is a machine learning codec for voice over HF and with RADAE v2 it can work down to -3 dB in a 860 Hz channel. I have seen people make voice contacts on it with as little as 5 watts of power across the Atlantic
Finally got a Meshtastic T-Deck! I asked a friend at the radio club which one I should buy (with or without an external antenna), and he said don’t, he had a spare. So I bought his, he only asked for $50, which is less than half of what they sell for new down here.
Although, I’m a little way out of the city, and I’m having trouble picking anyone else up, but I’m working on that. I also want to put a permanent node up at home, with a nice outdoor antenna. If anyone would like to recommend one, I’d love your opinion. I’m operating on LoRA, so 917MHz.
Finally got a Meshtastic T-Deck! I asked a friend at the radio club which one I should buy (with or without an external antenna), and he said don’t, he had a spare. So I bought his, he only asked for $50, which is less than half of what they sell for new down here.
Although, I’m a little way out of the city, and I’m having trouble picking anyone else up, but I’m working on that. I also want to put a permanent node up at home, with a nice outdoor antenna. If anyone would like to recommend one, I’d love your opinion. I’m operating on LoRA, so 917MHz.
If you have any ESP32s in your bench stock it would just be a matter of getting your hands on a LoRA module and figuring out how you want to put it together. JLCPCB has some really nice tools on their website that lets you design circuit boards, export Gerbers, and they will even print them up for you pretty cheap. A simple board with contacts for your micro controller, LoRa, power supply ciruits, and battery points would probably cost you around $25USD per five. You would just need to mount the passive components yourself and then solder the SoM to the contacts. If you aren't too knowledgable about intergrated circuitry you can find basic schematics for stuff like power supply circuits very easily online and then just adapt those to your Gerber designs.
as an alternative, if you have a tuner, or a something like a KX2/3/G90with a wide range internal tuner you can make a doublet using ladder line to the same dimensions. You will need to make a balun to go between the tuner and the ladder line. It will perform identically to the coax fed dipole, whilst also being able to be tuned across all bands 60-6m if your tuner is good enough. SWR is not an issue as balanced line/ladder line/open wire has extremely low loss, next to nothing in typical portable lengths even at 10:1 or more.
There is no need to split the wire-each side of the dipole and the ladder line can be one continuous piece of wire. Double up on the vine clips at the top.
We will sneed on every band, every mode, every format.
Humanity believes our old broadcast news will be one of the first things an alien civilization will know of us.
The second, if they ever visit? Us retards
shit like fake callsigns for KF bulletin broadcasts, doing it outside the ham bands is probably a better idea. There's lots of hams out there with mall cop personality disorder who'll get upset about people abusing their bands and waste retired sperg energy on trying to fox hunt or write stupid letters to the FCC.
