Bandwidth doesn’t put a hard limit on bitrate either. It’s one variable, but there’s also SNR (See Shannon). With a fixed bandwidth, you can have low bitrate and excellent low-SNR performance (think of Olivia), or you can have higher bitrates, and require stronger signals. For practical purposes though, you are not going to get highspeed internet on HF. But that’s what sharing is like. 🤷♂️
It’s a neat idea, but could be implemented entirely in software with a RTLSDR. Not my cup of tea, but I’m all for absolutely ANYTHING that gets more activity on V/UHF.
A longer term project goal for me would be a SBC and a couple RTLSDRs with a good antenna that simultaneously does APRS igating, streaming audio of all the local repeaters and a few simplex channels, and notifications like this project, and like the “adventure radio” project that uses CTCSS tones to trigger alerts. I think it would be a nice service to provide for locals. The only “trick” is that RTLSDRs can only simultaneously decode within a 2.5mhz window, so it would probably require a little scanning to cover everything, or too many sticks. Doing a project cheaply, but effectively, encourages copy-cats.
50 meters is enough for a 80m 1/2w dipole. And yes, google a “fan dipole” - you can hang multiple dipoles below each other with as little as a few inches of separation. However, the dipoles interact with each other, and getting it right gets more troublesome the more you do.
Neat idea. Odd that those diagonal telescoping rods don’t interfere with the yagi pattern?
I agree, a low power SWL license scheme would be fantastic. If you think you can convince your representative to advocate for it, go for it. Currently, even low power community FM is barely tolerated as a license class, and regulators tend to think of SWL as REQUIRING that the targeted audience be non-domestic.
That's basically what shortwave pirates are. Usually former ham transceivers modified to transmit out of band. The cost of licensing and building a shortwave broadcast station are immense. And there's the pesky problem of finding advertisers when the license scheme basically requires you to at least look like you are targeting non-domestic audiences. Hams have occasionally purchased time on existing transmitters when it's cheap, but as far as "experimental modes" go, it would typically have to be something that can be modulated by an AM transmitter.
It cannot be parity because, unlike the fiber Internet, it's fundamentally limited by the HF spectrum and the cost of this type of operation. Most traders will not have this option and will get fleeced by those with the resources.
Agreed. This isn't a responsible use of spectrum, unlike, say commercial shortwave broadcasting. This practice is purely about gaining a pay-for-play advantage in high frequency stock trading over traders that can "only" communicate across the country via fiber internet links. No net benefit, even for the stock traders, who will be hurt by this more often than they can take advantage of it. Sure, sell HF licenses to commercial users, but this is a bad idea.
fyi, nearly everyone that succeeds in achieving morse proficiency recommend strongly against any sort of visual cues like this. It's an auditory "language" and adding visual interpretation steps just adds cognitive load and hurts in the long run. It may be fine if your goal is to learn max 5 words per minute or something extremely slow.
Yes. This is a setting in the menu. Audio source is selectable separately for -D and non-D, so one of them can use the mic and one can use the aux, or whatever you want. I believe it also recalls the various DSP settings as well, so you can set things up how you like for phone, and for digi and easily toggle back and forth.
It's not about a pre-set per-se, but about having 2 custom U/LSB profiles.
Put the volt-meter in series with a switch or momentary button. They tend to draw a little power, so you don’t want it draining your battery when you are not using it. If you stick a cig (accessory) port in there too, you could plug in other things, or a usb charger or whatever if needed. I’ve used my pota battery to run a small 12v air compressor, for instance.
Amateur radios are generally spec’d at 13.8v plus or minus either 10% or 15% so that they work on a non-running car (12.something volts) or if an alternator is running a bit hot. A 100W radio like this is pretty much always going to require around 20amps at full power -but they have adjustable transmit power. They don’t transmit as well at the lower voltage range, but most people don’t worry about it.
It’s a (kind of silly) throwback to the radios that armies used in the first half of the 20th century that were large enough to necessitate a dedicated person backpacking them around everywhere. It’s still common in ham radio like other traditionalist terms. “Portable station” is more accurate, but maybe boring?
There’s negligible advantage in loss going from pl259 to N connectors on HF. You don’t have the kind of losses you do on VHF and especially UHF. The only time N is really nice is when you need an intrinsically weatherproof connector -but this is mounted inside the weatherproof box.
If you want slightly better loss specs AND a more convenient, quicker connector, BNC is great. But PL259, as I said, is fine.
I would look at fabbing up a box that fits snugly, rather than “clamping” them. That could protect against puncture as well. A 3d print or thin plywood glued together would be fine.
Is this for FM? Most people are using vertically polarized antennas for that. You could turn it on it’s side, and feed that coax sideways for at least a few feet.
The trick with a friend and JS8Call would be to utilize heartbeats and script up some sort of notification alert when a path opens.
If you don’t have trees and want an easy, portable solution. Buy a $20 20 foot “crappie” fishing pole on your favorite online retailer, and run a 20m 1/4wave vertical wire up it. Add between 4 and 8 radials on the ground, and craft up a simple guy system with some rope and tent pegs. Cheap, lightweight, and highly effective, especially at this point in the solar cycle. Cut some shorter wires for higher bands and you can pick and choose which one to hoist on a given outing. The only downside is that right now, specifically js8call activity is still heavily on 40m. You will make boatloads of ft8 contacts on 20 though.
An EFHW can be oriented as an inverted-V, it’s just that it’s fed at the end rather than in the middle (at the top). If that’s how you set it up, the main difference is some transformer losses in the EFHW, but it can operate on all harmonics rather than just odd harmonic bands. A center fed inverted v may be a little more tolerant with regards to tuning the length. Centre-fed is going to be more “idiot proof” in that respect and possibly easier as a first antenna.
On HF, unfortunately, physics is going to keep you from having high speed data. The Shannon–Hartley theorem puts a ceiling on the maximum bitrate of a channel in the presence of noise. If you are on HF with your 100w transceiver and a dipole antenna, your signals are always going to be weak enough on the other end of a skywave contact to limit your data throughput. Even given a magical ham prodigy that invents the best mode imaginable, it’s going to be Kbps, not Mbps. If you want to learn about the development of open source, higher throughput digital modes for HF, I highly recommend David Rowe’s blog on the development of FreeDV over the years. There’s even a recent move to general data in addition to digital voice. However, we are talking about single digit Kbps digital. There are some other modems used by the Winlink folk that are a little higher. The drop of the baudrate limit will just remove an artificial contraint, and headache, on that development.
On line-of-sight VHF and up connections, it gets easier and easier as you have higher gain antennas pointed at each other and lower natural noise figures.