Basic VHF and UHF Fundamentals
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- čas přidán 10. 09. 2024
- Basic VHF and UHF Fundamentals
Antennas are a very important component of communication systems. By definition, an antenna is a device used to transform an RF signal, traveling on a conductor, into an electromagnetic wave in free space. Antennas demonstrate a property known as reciprocity, which means that an antenna will maintain the same characteristics regardless if it is transmitting or receiving. Most antennas are resonant devices, which operate efficiently over a relatively narrow frequency band. An antenna must be tuned to the same frequency band of the radio system to which it is connected, otherwise the reception and the transmission will be impaired. When a signal is fed into an antenna, the antenna will emit radiation distributed in space in a certain way. A graphical representation of the relative distribution of the radiated power in space is called a radiation pattern.
When a CZcamsr doesn't bullshit, puts 2 hours of reading into 5 mins of clear, concise awesomeness, videos like this happen.
Much respect and thanks,Sir.
I just cleared my general grade in India. Waiting for my license.
Love and regards from India.
73
There isn't one piece of fluff in this video, the information is like reading notes taken from a two hour lecture.... great job
Simplicity at its finest, why can't all videos be like this
This was one of the best CZcams videos I've ever seen. The information with presented quickly and concisely with good visual aids. I can't believe people complain about someone speaking too quickly. I'm from the south and I still thought this was great. :-) if you want to listen slower simply tell CZcams to play the video at a slower speed. The rest of us can keep up just fine. Most videos lag and have a bunch of nonsense filler time wasting garbage. Kudos for the concise presentation that did not waste my time. I'm forwarding this to some friends who are aspiring to be ham radio operators.
Well said
Pro-tip, playback at 0.75x speed to have a drunk sounding guy doing the voiceover. Informative and entertaining at the same time!
Dan does talk a little too quickly so I did find this helped. Downside was it sounded so much like a genuine drunk I couldn't concentrate from laughing so much !
When entertainment doesn't do it for you anymore, and you find pleasure in video lessons and courses
Dan Vanevenhoven: Dude, you just answered a bunch of questions I had on this subject in a clear, concise manner. Thank you! Thank you! Thank you!
A small, mostly irrelevant note:
I wasn't sure if the concept of simplex and half/full duplex were the same as those used in digital systems communications, but it seems they are after some research.
The walkie-talkie example was labeled as being simplex in this video, but I believe this would more accurately be considered half-duplex, since the communication is bi-directional but transmit and receive cannot be performed simultaneously.
The example of using separate frequencies for transmit and receive to achieve concurrent transmission and reception would then be full-duplex.
Anyway, great content thank you for the video!
Thank you very much for this information. Presentation is lively and never felt sleepy.
Thank you very much (from the ACT in Australia)!
Fantastic Job , Wish everyone doing tutorials on CZcams followed the same method you do , I could learn lots
Thank you for this video. It is the most informative one I've found on CZcams! Again, from someone just getting into HAM and VHF/UHF this was extremely helpful!
Thank GOD !! I just crawled out of a cave...or under a rock...I don't understand this hand held radio. YOUR VIDEO is a great explaination...I'm beginning to understand. I subscribed. Thanks. I may have questions to follow.
Tim Myles e
Very nice information delivery! Future Ham radio operator. Thanks for being a part of my studies.
Very well done! This should many new hams.
AA5JD, John
Bravo........hey a friend of mine.........had a broadcast station he used the moon as repeater....deflector......cheers
Spot on and nice presentation.
good luck to everyone in your two way radio excursions. Have fun.
Thank you! This video helped a lot. The way it was done was for beginners and that my friend is what I am!
Very good presentation - thanks! A pity so many comments are worthless, makes one wonder about the educational system.
Good information delivered at fast-forward speed.
You can also calculate the height of an antenna by knowing that 2 degrees of arc is equal to to 60 min of latitude or 60 nautical miles, this only works for N - S unless you are with in 300 miles of the equator than it also works for E - W.
Aren't we full of ourself😢
can a tv antenna be use for transmitting a radio signal to receivers
Where were these videos when I was still active duty? Great vids full of useful information. Great job! 👌
Well done and very helpful. Thanks.
Thank you. Short and sweet.
Did Mr. Plinkett and Scientist Man merge together?
Thanks, this was a great overview-- and local examples too. I found this by chance trying to figure out why I can't get WLUK in the Fox cities any more. Makes more sense now. Need to raise the VHF antenna.
This video is freakin' gold......huge insight here. Thank You, Sir! KI5JAD, Devine, TX
Great info and concise, thank you
Glad it was helpful!
1:15 - - VHF + UHF uses line-of-sight propagation.
Line-of-sight is the direct propagation of radio waves between antennas that are visible to each other (the most common of radio propagation modes).
1:37 - - *maximum distance of line-of-site transmissions is about 25 miles* (due to curvature of earth; referred to as the radio horizon); slightly farther than actual sight bc radio waves bend; *however the higher the frequency - the less they bend.* *You can extend the range of your communications on VHF + higher frequencies by increasing the antenna height - 10 ft of antenna height is like doubling your power output*
Agreed, This is a basic video on VHF and UHF. We could discuss VHF and UHF propagation all day and that's not what the video is for. Its only fundamentals
Quick question, isnt that duplex referred to as half duplex? Because those transceivers can only send or receive, not both at any given time. Full duplex you'd be able to listen while you talk, right?
It’s still a foreign language to me, but it helped! It’s less foreign than it was 6 minutes ago.
That right Jay, very cool.
Clear and without unneccidrisksowkwnsaly information. Good video. Like earned
Glad it was helpful!
Very helpful. I want buy land out in the middle of nowhere and build on it. So communication with home will be important, as cell service might be non existent. I figure why not have a mobile base station and a home base. So I can talk to home that would be around 1000 miles away, while I'm freezing up north. Cool stuff here.
Thanks
Sir I have just one question. What if the distance between two ufh baofeng hand held radio is used, distance Is about 4km only. But the barrier is a hill and rainforest. Will I still be able to commiunicate with the other one?
Very good vid but speech too fast. I guess that's what the pause button is for.
Running the video at .75 speed helps quite a bit.
Makes him sound a bit intoxicated, but what the hay.
Wow.... Thanks!!! This was extremely helpful and educational!
hello. i have two questions for you sir. hope u can help out in my questions.
what is the construction and operation of the vhf transmitter?
what is the advantages and disadvantages for vhf transmitter?
thanks :)
knew most of it, but was flicking thru vids so watched it. Wil be very informative video for new hams
Thanks i'm studying for my ham radio test
Thanks for the education my friend
Ever ask about how cars work and get an explanation about the highway system?
Informative video
Thank you for making it
Wow! Wonderful explanation. Simplex, the way my mind works😊
Thank you Dan!! KF5LUR
I wish CZcams existed when I got my General back in the 1990s. It takes a lot of reading to summarize what this 6 minute video just showed. This generation has it so easy!
Can I add an extension to my VHF base station , if yes, how many feet can I add ?
I have a question.
I have been told that that 243.000 and 282.8 MHz are emergency frequencies.
On paper they should belong to VHF spectrum, but they appear to be the "UHF emergency frequencies". Why is that? Why are they listed in the set of UHF while they evidently belong to VHF spectrum?
Thank you for your answer.
www.ntia.doc.gov/files/ntia/publications/january_2016_spectrum_wall_chart.pdf VHF is 30Mhz to 300Mhz and UHF is 300Mhz to 3Ghz
where did you buy that radio?
Olá, Dan! Tudo bem?
Parabéns por sua exposição básica dos fundamentos VHF e UHF.
Interesting. Fast, but interesting. I surprised myself by keeping up! Good information.
Thank you
Very good but fast :)
I play it in 75% speed, it works much better... 👍🏻
EXCELLENT!!
What is with the weird inflections in The voice?
can you refer a tutorial guide on tuning to different frequencies using avr mcu?
great clarity. thanx
Why is the earth shown with a curve?
the explanations are quite good but one request pls if you could speak slowly, some are not very familiar with the terms and couldn't catch up with what you're saying. thank you
there are also zero breaks more than a microsecond....cant process the information without constantly replaying parts
anything over ehf?
Tankes
THANK YOU SIR!
Very helpful video 👍
3khz is the (measured) frequency when my wife yells at me… yeah the wave goes pretty far and do penetrate walls through my neighbors.
Man the narration is fast, too fast. While VHF and UHF appear capable of pentrating walls, what is happening in reality the shorter wave length can find and pass through gaps in a building's structure, also they are easily reflected inside the struvtur. However there is limit how higher frequencies can be effective
Since professional radio transmission broadcast stations transmit with such high power, why can't the government allow HAM radio operators to transmit not on 5W but on 10W. So what? It would be a big improvement!
Frank Reiser KB2VNG
Frank Reiser Video/Audio Service
Caldwell, NJ
Hi, so Can I use somehow HF antennas/base radio to use VHF communication like use walkie talkie's with HF antennas?
can we transmit GPS signals through VHF RF to track the position of a vehicle without internet?
asif shafiq You can use two prepaid mobile phones with the push to talk (PTT) feature. Tape one to the underside of a vehicle, and hold on to the other one, and press the PTT button to track the vehicle. Or you can use two smart phones, both with Prey Anti Theft software pre-installed, to do the same thing. It's kind of expensive to do as a regular citizen, but if it's within your budget, you can definitely make it work.
Hello I am hoping you can help me out. I recently Bought a set of older fm intercoms by radio shack .They are FM transmitters. From what I just learned in the video earlier is the FM - vhf .Doe not travel though walls or solid objects. Bear with me as I try to wrap my head around all this. So I got the intercoms to talk to my wife in the bed room. Only 15 feet from where my unit would be. But CAN YOU TELL ME IF THE PLASTER HARD WALLS IN OUR APPARTMENT IS WHAT IS BLOCKING THE SIGNAL AND IF SO .Would I faired better with uhf transmitter - intercoms. That is in fact if they make uhf intercoms .It really blew my mind that the set did not function in our small 1 bedroom apt. .Although this apartment does not have drywall .The walls are rock hard plaster. Even making it a pain to hang a picture on them. But the wifi signal seems to flow though to the bedroom fine. Is it a rule that the lower the frequency the easier it can flow though or around obstructions . I am buying a set of inexpensive walkie radios . Name and specs as follows Retevis H777 Walkie Talkie 1500mAh UHF .In your opinion how should they perform .I need them no longer than around 1.5 to 2 miles max .Thank You for the video and I appreciate any added advice or knowledge you could pass on .God Bless and good day
timothy thomas Impossible that signal would not penetrate your wall. I reckon your transceivers do not work anymore.
timothy thomas Most of the FM intercoms actually don't use VHF or UHF over the air, What most intercoms actually do (the ones that plug into the wall outlet) is send the signal down the electrical line and that could explain your problem. The electrical service in your house is made of 2 phases 180 deg out from each other (This is what allows you to get 240 Volts access in your house ie. 2-120 volt legs 180 deg out of phase ) The problem with regular house hold intercoms is, if you have one intercom on one phase in your house and the other unit on the other phase in most cases they will not talk to each other. In my case here, I actually had to move the intercom from the living room to the kitchen. To get the two intercoms talking to each other from upstairs to downstairs in my electronics shop in the basement.
Dan Vanevenhoven Thank You sir .I have since bought a set of china made retivis kenwood knockoffs ,two way uhf radios and got the cb mic attacments .works great up to around .5 mile in town .I am getting a baofeng ham radio .Next and may have a few more questions.About repeaters etc.Have not delivery yet.Thank You and God Bless .
good video but u speak too fast
Helpful, thanks
A second between sentences would be tremendously helpful. Good info to be had but it starts becoming hard to follow after about halfway through.
Good information but it would be better if you slow down.
so which to use
Too bad you didn't have more of these vids to help with this GROL exam (sigh).
thanks
thanks alot
Dan Vanevenhoven
thanks
Think for gd tutorial. But please can u send m the Same tuto in pdf doc for me learning because a have difficult with English speak. Please n sorry for m bad Handwriting
So what happens when there are 100 people all want to use a repeater at the same time to talk to their buddy?
Quinton Divide
CQ CQ CQ! Great video!
Wait, so now, you are saying the earth is not flat?
consider adding more than a millisecond of dead air between statements buddy
Is i can see indian TV channels
Can I use a vhf antenna with a uhf radio?
The only way that works is if the antenna is a vhf/uhf antenna.
What did you say
Only mistake in this video is that the earth is flat not curved
Ward Stravenue
See it in use here: czcams.com/video/cqT-pjrBCqg/video.html
I like it
Nice video but feels like a BULLET train ride...Cheers
Jenkins Ports
Vietnam is using hertz to kill people. Although he has not died, he has also fallen several times. His address is in District 1, his son, thanks to the law for help
Good
Lindsay Garden
Good animation but dang the speaker really needs to work on speach skills. Please slow it down and relax.
Here from RLM lmao 😂
Sounds a bit like a tamed down version of Mr Plinkett lol
I have smoke coming out of my ears
😂😂No doubt