Frequency and Wavelength and Speed of Light

Рет қаралды 3,262

2 ай бұрын

Wavelength and Frequency can be worked out once we understand the speed of light. By dividing the frequency by 300, we achieve the exact wavelength. Try it yourself, divide 300 by 3.75 and you get 80m. That's the 80m band. In this video we discuss mains frequency, 3-phase, audio frequency and in particular, the famous 300 - to - 3000 Hz frequencies ideal for communications voice and also sound frequencies. Enjoy! Callum.
Here's the SSB AM and FM video: • The REAL Difference Be...
More of this series here: • RSGB Amateur Radio Fou...

Пікірлер: 70

@ham-radio 2 ай бұрын

In the U. S., people often say 110 and 220 volts. It has not been that for decades. It is 120 and 240VAC. In practice, it can actually be higher depending on your location. That is, higher if your "drop" is closer to the substation. The demonstration you did speaking with a limited bandwidth was brilliant! That demo will be remembered by all who heard it. Thanks for another teaching video. 73, Jim W6LG

@paulsengupta971 2 ай бұрын

The 230V "standardised European" voltage is also a bit of a kludge. The UK is 240V, always has been. Some countries in mainland Europe are 230V, some 220V. They wanted to have a standard European voltage so they settled on 230V...but they set the tolerance so that it encompassed 220V to 240V. No one actually changed their voltage, just that it's now declared at 230V.

@DXCommanderHQ 2 ай бұрын

Hello Jim.. Yes, a quick spin of the EQ..! Good to see you in the comments old friend.

@DXCommanderHQ 2 ай бұрын

Paul.. It's all nit-picking. This one is about frequency and wavelength.. But we all digress.

@kingduckford 2 ай бұрын

When I monitored my plug voltage for a while, I noticed that during warmer winter days it would be closer to 125 volts, while during very cold nights it would drop down to 118 volts. My assumption was the heavy use of electric heat causing some drop. I suppose it can shift with current demand over the grid.

@Ibsonlovesyou 2 ай бұрын

I have my intermediate exam booked for April. Id love it if you did a playlist of going through the books, you explain things very well and bring great context to the wording. A great help for someone like me. Thank you Cal.

@DXCommanderHQ 2 ай бұрын

I would like to BUT I am not good at "electronics" which quite a bit of the Intermediate is... I will keep making these anyway so most / some of it might come to be published.

@Ibsonlovesyou 2 ай бұрын

There is a lot of electronics! its not my forte either which is making it harder. That's great though, I will be watching anything you publish as usual. MW7FMD@@DXCommanderHQ

@codybooth 2 ай бұрын

Absolutely an excellent demonstration Cal!!!

@DXCommanderHQ 2 ай бұрын

Thank you kindly!

@lejendpolevault5345 Ай бұрын

Passed the Foundation today, a huge thanks to you for helping me understand this game better. Couldn't have done it without you.

@DXCommanderHQ Ай бұрын

Wow! Fabulous news. Good work!

@hamgammonable 2 ай бұрын

I have done Standard Grade and Higher Physics and Tech Studies (Scottish Qualifications Secondary School) and in under 10 minutes you give one of the best explanations of Frequency and Wavelength I have ever seen. I wish we had the examples given and I think most kids would’ve understood the concepts in one class not 3.

@DXCommanderHQ 2 ай бұрын

Ah. Thank you so much!

@2e0fjjvlogs32 2 ай бұрын

My brother is learning from you. What you talk about is fantastic. Keep up the good work Callum.

@DXCommanderHQ 2 ай бұрын

Hey Thanks!

@jasonodette8607 2 ай бұрын

Always appreciated Calum 👍

@DXCommanderHQ 2 ай бұрын

Legend!

@rowdyron4111 2 ай бұрын

Stellar presentation, thank you!

@DXCommanderHQ 2 ай бұрын

Glad you enjoyed it!

@stuartmccloud307 2 ай бұрын

Holy Shit, I thought I needed charts to work out wavelength, This makes perfect sense now! Thanks Callum:)

@DXCommanderHQ 2 ай бұрын

Woo-Hoo! LOL

@richardmillican7733 2 ай бұрын

Gone are the days where this was touched upon in secondary physics class (secondary is high school to any American viewers) I remember this exact bit of science being taught to me in around 1983, I'd have been 15, after school we would annoy the neighbours with our CB radios. I suppose today's equivalent would be computer code lessons followed by dashing home to make TikTok videos!

@DXCommanderHQ 2 ай бұрын

Wow.. I had no idea this was taught in schools.. School was a bit of a haze for me.

@stargazer7644 2 ай бұрын

"By dividing the frequency by 300, we achieve the exact wavelength." Exact is a very strong word. To get the EXACT wavelength you need to divide the frequency by 299.792458 in a vacuum, or by 299.702547 in air :)

@DXCommanderHQ 2 ай бұрын

And what value is that to a learner..? Don't answer! :)

@thork0tjt515 2 ай бұрын

Good stuff! 73

@benjaminkoch2703 2 ай бұрын

Great job. I'm learning for my foundation license in Germany this summer and I'm very happy with your explanation.

@DXCommanderHQ 2 ай бұрын

Great!

@daveengstrom9250 2 ай бұрын

Using meters sure makes it easy. Thanks.

@DXCommanderHQ 2 ай бұрын

No problem 👍

@DonzLockz 2 ай бұрын

Good refresh Callum, if I dont use it, I lose it.😂

@DXCommanderHQ 2 ай бұрын

Same!!

@PedroskiClimb 2 ай бұрын

This metres malarkey makes so much more sense than trying to do things in feet and inches. Using SI units shoud be the standard amongst hams across the world and I don't know why hams in some areas still cling onto feet and inches! :)

@DXCommanderHQ 2 ай бұрын

I'm not saying anything! :)

@rayb228 2 ай бұрын

Brilliant.....How soon you forget 🙂

@pixeluser175 2 ай бұрын

Oh that nasty velocity factor...

@dondonaldson1684 2 ай бұрын

Love this comment!

@rickbattle5706 2 ай бұрын

Jolly good fun.

@w8lvradio 2 ай бұрын

While it won't really help for writing a test, here are some additional fun facts: In the UK, the AC cycle always starts on the left side, and in the US of course it starts on the right side.😅 And in Australia, the AC is inverted, and with the skin effect, of course it swirls to the left on the outer portion of the conductor, same as the toilet water does 😅. In France, even at potential, electrons sometimes outright stop in a conductor as they known to go on strike. This is called Passive Impedance😂 Canada's grid is very efficient, as the conductors in the cold Northern Grid Interconnect are usually superconductive most of the year 😅

@DXCommanderHQ 2 ай бұрын

HAHA - Very good! :)

@PedroskiClimb 2 ай бұрын

Mistake in your description Cal: "By dividing the frequency by 300, we achieve the exact wavelength". It's the other way round - divide 300 by the frequency (in Mhz).

@DXCommanderHQ 2 ай бұрын

well spotted

@PedroskiClimb 2 ай бұрын

@@DXCommanderHQmarkng students' work at uni back a few years back has left its mark on me!

@HAMRADIODUDE 2 ай бұрын

Thanks

@DXCommanderHQ 2 ай бұрын

Woo-Hoo!

@HAMRADIODUDE 2 ай бұрын

@@DXCommanderHQ You actually made me inadvertently realize I just did some math wrong in a video :) Time to start that one over HAH! cheers

@user-tl5tt5yw3c 2 ай бұрын

I was wondering about the time involved,with the peak of a wave or amplitude of the wave does a higher amplitude wave take more time to complete than a lower amplitude wave even if they are the same frequency ? Thanks cal cheers

@DXCommanderHQ 2 ай бұрын

Only the frequency changes regardless of amplitude.

@bigphillAchtung 2 ай бұрын

just following on from that caller you had on the last live stream, heres a video which starts explaining the WSPR theory and flight MH370. Thought you might like to watch :)

@bigphillAchtung 2 ай бұрын

kzfaq.info/get/bejne/j5t7bKtzzrDUpZ8.html

@DXCommanderHQ 2 ай бұрын

Yes, I watched the UK's Channel 5 program on MH370 last night (Part 3). Although, it was only a snippet of info.. Wendy said, "Now that looks like a ham radio guy!"

@bassangler73 2 ай бұрын

Cal, you know us musicians can't hear 💩 ! 😂😂 After years of standing in front of a 5150 amp I'm suffering...lol

@DXCommanderHQ 2 ай бұрын

HAHA

@jessemazo4791 2 ай бұрын

300 divided by 27 is 11.11111 indeed fact checks out mate!

@Eric10179 2 ай бұрын

I remember learning in high school physics class the equation: V=f x λ, little did I know at the time I’d become a ham and use that all the time in my daily life.

@DXCommanderHQ 2 ай бұрын

HAHA!

@GH0ST369 2 ай бұрын

I am a little confused 300 ÷ 14MHz is 21.428571428 and should be in the 20 m band do we round down? 300 ÷ 5.332MHz = 56.264066016 If so why would I round up to 60 m?

@paulsengupta971 2 ай бұрын

Yes, it's all approximate. What I find funny is that the 41m broadcast band is higher in frequency than the 40m ham band.

@DXCommanderHQ 2 ай бұрын

The 20m band is just as you said, the 21.5m band! :)

@godarklight 2 ай бұрын

Look up Dave Castlers "Way Off Base! Meter Designations vs Frequencies #921", skip about 9 minutes in. After 80m, nearly none of the bands designation are actually inside the band. It's worth keeping this in mind when building antennas!