Nothing makes you hate cars more than living on a busy street, forced to listen to their din day in and day out. >:(
Cities Aren't Loud: Cars Are Loud — Not Just Bikes
Urban noise is a common problem, and the vast majority of it is created by motor vehicles. Noise is far too often dismissed as a minor nuisance, rather than the legitimate health issue that it is.The book "Curbing Traffic" has a chapter about the health impacts of noise pollution. I explore the research in the book, and visit Delft, the city that is highlighted in the book as being a shining example of what can happen when noise pollution is taken seriously.
This video explores the problem that farting cars, farting motorcycles, and farting mopeds create in our cities.
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From here:
There is no 'free' market, and there never has been. The 'free' market is predicated on the belief that all players will act honestly, and make informed choices based on available information. This is a completely false assumption, and has been proven so time after time.It completely ignores human nature whereby someone will always lie, cheat, and steal to achieve their own ends -- this is what we see here.
Industry players will always form cartels and collude in anti-consumer behavior -- price fixing being the prime example.
Without someone to keep corporations in line, the market would steadily skew to all of the power being in the hands of a few.
There is no such thing as a 'free' market, and there simply never has been. It's a utopian myth which can never be true.
People who go around spouting about the 'free' market are either naive, self deluded, or actively lying.
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damn, so we've had 11 years of this very thing getting worse.
when will people get it?! people keep voting for these pro corporate parties and it's depressing
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bazkie 👩🏼💻 bitplanes 🎵 likes this.
well, the same is happening here in the Netherlands. people have been voting the neoliberals into power for decades, despite things going to shit, and other parties being available here.
it's the propaganda that's working; most people still believe that free market capitalism is great, and it will take a lot more downfall before they understand it's shit.
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@bazkie about 10 years ago when I had learned just enough Dutch to read sites where younger folk hung out (and chat to them) I learned a fair few thought all the bicycles, good public transport (which folk in UK often envy!) and the high cost of learning to drive (which is same as UK) was imposed by "big government/EU" and they wanted to have cars just like young people in UK, enjoyed watching Top Gear and thought folk in UK and USA had more "freedom" (and those youths would be 30-40+ by now, many with families of their own)
At least you are highly unlikely to get Nexit as everyone can see the mess the UK is now in 5 years later..
@vfrmedia UK has been a lovely warning sign for us indeed!
..tho people have been voting far right the past few years despite Trump, so maybe most people don't really understand warning signs 😅
and about that dutch youth; keep in mind we've had neoliberal rule for decades now, so the whole "free market good, nationalization bad" has been really hammered in.
not sure if we'll get rid of it in my lifetime tbh. but most of the lovely social policies we have left stem from the more progressive governing we had before I was born 😅
btw why did you learn dutch? (maybe I asked before)
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I love pirate radio!
I don't know if it's actually a pirate station, here's an FM broadcaster near Quinault Lake here that plays all kinds of odds and ends with weird stuff in between. It might fall under LPFM, but I doubt the FCC would hassle them anyway since it's in the middle of nowhere and low power.
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@vfrmedia what's LPFM?
I wonder if maybe the FCC is a bit more relaxed these days since people listen to FM radio less (or well, I imagine that they do)
the "free market" is to economics what the frictionless spherical cow is to high school physics.
The very existence of corporations means there is no free market. Corporations are a legal construct of governments that grants a business (and later even a mere collection of assets) status as a district entity separated to some degree from the owners and workers within.
As such, there is no choice between "government vs corporations" because they are *two sides of the same coin*...it is all one big hegemony.
We have all been thoroughly conditioned to think otherwise for a couple of centuries now. It is thoroughly ingrained the minds of everyone in the "free world" that corporations are the capitalist free market and government is the socialist planned economy but that is pure BS.
The biggest economies in the world have arrived in the same place from two different directions...the US being a corporatocratic regime and China practising state capitalism.
As such deregulation just means re-regulation.
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The longer SMA-UHF cable isn't good. DC is fine, but at UHF it exhibits bad behavior. Going to remake it tomorrow.
The shorter cable is more or less fine enough.
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Speaking of 1.25m, check out what just showed up yesterday. :O
I've never seen TNC connectors in person before. :P
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Halo antennas are funky:
Although some writers consider the gap in the halo antenna's loop to distinguish it from a small loop antenna – since there is no DC connection between the two ends – that distinction is lost at RF: The close-bent high-voltage ends are connected capacitively, with a RF electrical connection completed through displacement current. Despite the abrupt reversal in voltage across the gap, the RF current bridging the gap is continuous (although possibly momentarily zero).
The gap in the halo is electrically equivalent to the tuning capacitor on a small loop, although its stray capacitance is not nearly as large as needed for a tuned loop: Capacitance is not needed since the halo antenna is already resonant, but since some small capacitive coupling is present anyway, the arms of the dipole are trimmed back from 97% of a quarter-wave each to restore resonance. Moreover, the halo ends are often pressed even closer together, to increase their mutual capacitance and the ends then cut even shorter to compensate, in order to make the radiation pattern even more nearly omnidirectional, and to produce even less wasteful vertical radiation (for a horizontally mounted halo).
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Let's see if this autotransformer works. #AmateurRadio #HamRadio
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All that work to build a parallel coax transformer and it still doesn't cover the whole 6m band. :(
I don't know why, but this LMR-240-75 was way harder to strip and break out into terminals than normal 50Ω LMR-240 is. :/
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Without doing any modelling, I would say it's probably not critical and it's likely to be a small fraction of a wavelength at the relevant frequency. I suspect it would just adjust where the gamma match attaches to the driven element, similar to, eg a J Pole feed point.
Of course, the correct way to answer this is to post a picture to QRZ.com and wait for 40 different "you're doing it wrong" posts that reference ARRL handbooks from the '40s
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In 2013 Yaesu introduced “System Fusion,” new technology utilizing C4FM 4-level FSK technology for transmitting digital voice data. The System Fusion communication protocol enables devices to analyze an incoming signal and automatically determine if it is using C4FM or conventional FM mode. System Fusion also enables data transfer at full rate with speeds reaching up to 9,600 bits per second.
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After doing some experimentation and discussing with @DD8SF , it seems like these two lengths work:
- 420-436 MHz: 26.2+10.5cm legs
- 435-450 MHz: 13.3+13.3cm legs
So a fan dipole with one OCF pair? 🤔 #AmateurRadio #HamRadio
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Finally back on 70cm. The dipole as-is can only cover the upper ~14 MHz of 70cm, but I'm going to see about getting some even smaller brass tubing so I can extend the legs even further. 🤔
And if that doesn't work, I have plenty of variable capacitors in my shack. 👍
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After switching to brass legs for my 70cm dipole for strength, I started trimming and filing them down to get something working.
- At ~132mm measured from the coax, it was resonating well at 424.5 MHz with an impedance of 44.24+j1.987 Ω and an SWR of 1.138.
- At ~107mm measured from the coax, the impedance at 436.0 MHz was approximately halved with an impedance of 23.41+j7.66 Ω and an SWR of 2.200.
Between the feed point and opposing UHF connector, the coax is about 114mm long, which is very close to two wavelengths.
(%i1) 1.14 / (%c / 436E6 * 0.83);
(%o1) 1.9975262006020027I'm getting the sneaking suspicion that the coax is doing unwanted impedance transformation, but I'm not sure. What do folks think?
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Series inductance electrically lengthens an antenna and series capacitance electrically shortens an antenna.
Does that mean shunt inductance electrically shortens an antenna and shunt capacitance electrically lengthens an antenna? :3c
Ended up getting longer legs (in aluminum because the hardware store was out of the copper tubing I like) and switching to a proper common mode choke winding pattern…and it just worked. It covers the entire 70cm band with SWR≤2! :O
I do have some more aluminum tubing that fits snugly inside these dipole legs, so I can make the legs telescoping to reduce the resonant frequency.
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Current project is a 70cm dipole, which I don't think is done too often. :P
Yes, that's a plastic bottle cap in the middle. The lengths one goes to when one doesn't have a 3-D printer. :(
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Bad SWR with this. Wondering if it's the length of the coax, which is pretty close to two wavelengths when accounting for the velocity factor, or if I messed up somewhere.
Anyway, I have some -61 mix ferrite beads on the way. :P
So I think I'm going to do a ½-wavelength metal stick, so 35cm to start, but I'm not sure about how much to space the gamma match rod from the radiating rod. :/
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Would it be possible to have a system of antennas like this?:
- Antenna 1 is built for Band 1 and has a filter with a passband that includes Band 1's frequencies.
- Antenna 2 is built for Band 2 and has a filter with a passband that includes Band 2's frequencies.
It'd be kind of like a trap on the feedline. 🤔
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https://www.electronics-notes.com/articles/antennas-propagation/antenna-diplexer/what-is-antenna-diplexer.php
Antenna Diplexer: Splitter / Combiner » Electronics Notes
An antenna diplexer or RF diplexer is used for splitting and combining antenna transmission lines and feeds on single or multiple frequencies.www.electronics-notes.com
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You should use a diplexer instead, containing a high and a low pass filter.
Impedance...
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Finally got my 6m dipole working with a -43 voltage balun. Since I mistakenly cut it a little too short all those months ago, it resonated at the upper end of the 6m band, so I had to tack on a tiny loading coil to add some inductance and bring the resonant frequency down to where I wanted.
The unfortunate thing is that the loading coil also significantly cut the bandwidth of the antenna + voltage balun. At some point, I'll build a new dipole and not cut it as much. :P
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That would work well if I had a wire dipole, but this one is comprised of painted copper pipe.
When I do make the new dipole, I plan on having bolt holes on the outer ends so I can attach stuff like additional length for 10m (probably with a trap) and capacitive hats. :3
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Wow, that's a really good SWR curve. 👀
Now I just need a trimmer capacitor to allow me to choose what that bandwidth covers. 👍
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Got a 6-meter QSO with a -61 toroid balun and the antenna mounted indoors! :D
035800 -13 0.1 1743 ~ CQ WA7CPA CN88
040017 Tx 947 ~ WA7CPA KM7BCS CN87
040030 -16 0.1 1746 ~ KM7BCS WA7CPA -11
040045 Tx 947 ~ WA7CPA KM7BCS R-16
040100 -15 0.1 1746 ~ KM7BCS WA7CPA RR73
040115 Tx 947 ~ WA7CPA KM7BCS 73like this
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bazkie 👩🏼💻 bitplanes 🎵
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Neil E. Hodges
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Daniel
in reply to Neil E. Hodges • • •every time I contemplate "upgrading" the stock exhaust on my bike, I remember it's already louder than a car exhaust.
Most car exhausts, anyway. Not the M3 that my neighbour across the road drives.
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Mira
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