I'm literally 4 classes away from an electrical engineering degree and this video is the first time anyone's ever explained to me what db actually are
@Alitar1212
Жыл бұрын
Literally same😂
@kartikeyak3425
2 жыл бұрын
13 years old but still helping so many students. I'm so glad i came across your channel!!
@aerohk
9 жыл бұрын
Something my professor tried to hide from me.
@jcx5750
8 жыл бұрын
+Aerohk Loooooool yes same here
@joshuaengay1350
7 жыл бұрын
Something my professor so lazy to teach thats why im here teaching myself
@IbrahimAli-kx9kp
5 жыл бұрын
Same here :D
@ShizzleMyChizzle
9 жыл бұрын
So passionate about teaching, absolute must watch channel for any electronic engineer.
@selvakumarr6672
4 жыл бұрын
Wow, I never imagined that I will get so real meaning of dBs. Thank you so much for this. Recently i came across working with dBs in my profession, I asked many of my friends on what is the real world meaning of dBs, Frankly nobody able to explain anything closer to this. Keep up your wonderful work.
@AlienRelics
3 жыл бұрын
Are you trying to use a plural of dB by adding an "s"? That doesn't really work, I don't think there is a plural for a symbol. I was thinking you were trying to say dBspl or dBm or something like that.
@selvakumarr6672
3 жыл бұрын
@@AlienRelics . Yup that was my mistake on adding 's.
@teddyr101
9 жыл бұрын
"-6dbr", the industry standard for half a rabbit?
@CairosNaobum
6 жыл бұрын
is "rabbit" a power or a magnitude ?
@retrobrw919
9 жыл бұрын
I'm so glad I found the EEVBlog. It's such great supplement to my college studies in Electronics Engineering Technology!
@HamedAdefuwa
3 жыл бұрын
dave, ur approach is just genius, everytime I watch your videos I get filled with "dont worry about it, its easy to understand" - all other engineering videos fill me with despair, like I've got to go back and complete 50 physics text books before I can do EE.
@EscapeMCP
8 жыл бұрын
Should have included how to work out dB's inbetween decades e.g.: 20:1 is +6dB for x2 and +20dB for x10 = +26dB 1:50 is -40db for /100 and then +6dB for *2 = -34dB Such an elegant system. You can always get pretty accurate ballpark figures without any need for calculators.
@martinda7446
10 жыл бұрын
That glass is -3dB down, it had PowerAde in it.
@HighestRank
10 жыл бұрын
*---* 3dB down is 3dB up.
@martinda7446
10 жыл бұрын
Rýán Túçk Haha ok.
@JennyEverywhere
8 жыл бұрын
If someone wants to really understand logarithms, they should study how to use a slide rule. It gets the concept of logs deep into how you calculate things. There's even dedicated rules designed with radio, electronics, or engineering in mind.
@eighthourlunch
8 жыл бұрын
Excellent explanation, thank you. I wish my college professors had been as competent at distilling ideas like these into something understandable.
@tejeshwvardhan1165
9 жыл бұрын
believe me if i ask my teacher "what is dB". in return i would get "very good question????????????"
@khadijaqayyum8360
5 жыл бұрын
haha.. ideed a very good question
@DianneStudio
4 жыл бұрын
Very nice informative video!! Cant digest!! lolz! how to calculate the fan's sound! that's y I am here! I am like doped .. lolz!! DB in audibility ... thank you
@salat
14 жыл бұрын
@shodanxx: I'm a ham too and I it's easy to rembember: If you double the voltage in a circuit,the current doubles too and since P=I*U we get: 3 db(V) which leads to a an increase of 3db(W) e.g. with a 1 Ohm circuit: from 1V to 2Volts there's a ~6db(V) gain from 1W (1V * (1V/1Ohm)) to 4Watts (2V * (2V/1 Ohm)) we get 6b(W) gain that's the reason for 10*log(p1/p2) for power and 20*log(v1/v2) for voltage.. 73, DO9SAS
@Richard_Broom_Photography
10 жыл бұрын
An excellent video. Swept away years of misunderstanding.
@dannyleefye
7 жыл бұрын
According to my Spectrum Analyzer it looks like you have a 50 Hz hum in your audio. When it is not obscured, I also see a signal at 100 Hz which is usually a bit stronger. So maybe you have a ground loop problem? I am not trying to be goofy or anything like that, I just wanted to let you know. Thanks much for the GREAT videos! P.S. I am in 60 Hz land, so I know it is not on my end.
@1SmokedTurkey1
11 жыл бұрын
Better than my Communication Theory prof's explanation, which took more than 2 classes and I still didn't get it. Thanks!
@hoofbags
3 жыл бұрын
For some reason, as with quite a few amateur electronics hobbyists, I had a blind spot for dB. As usual, your explanation is hugely helpful. Many thanks. (o:
@HighestRank
10 жыл бұрын
Here's the straight forward equation minus the derpworthy typos and readability issues: (V.out/V.in)·Log(20)=dB.V. (P.out/P.in)Log(10)=dBm. •Inverse formula: dB.V/20=V.out. dBm/10=P.out. •Here is the -3dB. that you hear so much about: 0-3.dBx./20=0.707. 0.707Log(20)=0-3dBx.
@2013Aleksey2013
9 жыл бұрын
I'm still not quite used to describing electrical quantities in terms of decibels. The input signal has an amplitude of 500mV while the output signal is 1 Volt, so the input signal gets amplified by a factor of 2 or +6.0206dB. I was curious as to how the equation dB = 20*(log Vout/Vin) could be rearranged to solve for Vout assuming dB and Vin are known. So, dB/20 = log Vout/Vin; Vout/Vin = 10^dB/20; Vout = Vin*(10^dB/20); Vout = Vin/10^-dB/20
@szabojozsef7873
6 жыл бұрын
Hello. I need explanation of what is dBm in RF communication. For example I have two RF Module. The Transmit Power is 14dBm.What dose this mean? After connection RSSI is -9 dBm.What dose this mean? Can you help me please?
@HazeAnderson
4 жыл бұрын
When you see dBm you can read the spec as "above 1 milliwatt" so Transmit Power is 14dB above 1 milliwatt. 14dB is roughly 10dB + 3dB so we can read 14dBm as a tenfold increase of 1mW to 10mW and then roughly an increase of double for approximately 20mW. So Transmit Power can deliver a bit more than 20mW into a load WITHOUT regard for its impedance. (If the specification does not specify this impedance then it is *usually assumed* to be 600 ohms.) I leave deriving the wattage for -9dBm as an exercise for reader. 😂
@fuahuahuatime5196
6 жыл бұрын
Thank you for the video! I learned about dB back in school but never grasped the idea, and it's always been my biggest weakness.
@coyohti
Жыл бұрын
"Because it's nicer when things get more complex." This video has not only helped me understand dB better but the above quote has helped me understand why my dad (an electrical engineer) was the way he was. 😉
@vk3hau
7 жыл бұрын
And don't forget dBi " decibel over isotropic Antenna"
@dylan_king1870
6 жыл бұрын
this was such a great explanation and your excitement made it really enjoyable. thanks.
@ericjw7
10 жыл бұрын
Thanks for all your videos, I've gotten something out of all of them
@asdwjure
12 жыл бұрын
I'm 12 so this is too hard for me. lol! :P
@LynkedVideos
10 жыл бұрын
Why should we care about the "ancient" unit of Bel? In 1920, Bell Telephone created the Bel to represent the base10 log of a power ratio. The name of the new standard for measurement was a dedication to Alexander Graham Bell. Decibel was the recommended unit. Since the decibel is an exponential unit of power measurement, its use with potential is a derivation. Assuming that a change in potential results in a linear current response, then we can derive a measurement in decibels to describe the voltage change in this ideal system; however, the measurement still defines a power ratio. Thus, I suggest that we should care about the Bel and its creation. In regard to your glass of milk, I will assume that the vessel is a perfect cylinder. You now have more power than you need, because with only half the columnar height (potential), you will consume fluid at half of the rate (current) as full. Next time I suggest buying proper conical glassware so that you can supply power at a rate that is commensurate with its remaining potential. Do you like martinis? ;oP Party on, Dave!
@HighestRank
10 жыл бұрын
Use a straw.
@RW1701
11 жыл бұрын
What are the units for one chicken? Ch? -6dBCh please :) Does that look like a curse to anyone else? haha
@kevinchau5336
4 жыл бұрын
I'm about to graduate from college with an EE degree, I've learned more from your channel than the UofA has taught me.
@BariumCobaltNitrog3n
2 жыл бұрын
You just weren't paying attention. Also you can't pause and replay a college prof thousands of times.
@EdMatzenik
11 жыл бұрын
Here's a formula I use to mix music. 1. mix it quick and rough. 2. round everything to the nearest round figure of dBs (-7.9 becomes 8.00). Now if you accidently bump a fader, you'll know. 3. Every time you listen to the music remix it in even dB terms to the following: 1 dB up or down is the difference when a musician played note a little different, 2 dB sounds like you turned it up or down a little bit, + or -3 db is a lot. Any more than 3... must have been ridiculous to start with.
@willowillotech7029
3 жыл бұрын
thanks LOL LOL you are very encouraging, well done
@2ndlars
11 жыл бұрын
When you're talking percieved volume you're talking psycho acoustics. Twice the amplitude of sound will not sound twice as loud. That's (if I remember correctly) because it's not twice as far above your hearing threshold. AND it only holds true for what's called "normal hearing" because people with a hearing loss will have a smaller range of hearing.
@RW1701
11 жыл бұрын
This guy is so enthusiastic!! How can you not get excited about electronics listening to that voice!! This has really tickled me haha
@frankreiserm.s.8039
4 жыл бұрын
i used to have a ton of electronic, math and science T shirts. Then I got fat, and they did not fit me anymore. So, I threw them away. I am sorry now that I did that because I lost the weight. I have an IQ of 120 and am great at memorizing and understanding anything that is not mathematical. Even though I do not understand calculus, I love electronics and EE. Frank Frank Reiser Video/Audio Service
@abberdakas6294
8 жыл бұрын
Thanks Dave!! Some subjects in class leave me more confused than i was when I started, so I come home and watch your videos and it all becomes clear. Excellent video
@BigNate84
10 жыл бұрын
I have a question pertaining to the 19:08 minute mark of the video. How come -3 dBm is = to 0.5 mW? Above that I am seeing -6 dBv also = to 0.5 v. Is this because orders of magnitudes use 20 Log and power uses 10 Log? Or is this an error in the white board math? The video covered the rules of thumb for magnitude which makes sense to me, I'm just wondering what the rules of thumb for power are if they are different? Thanks!
@BigNate84
10 жыл бұрын
I guess I was expecting -3 dBm to be = to 0.707 mW based on the rules of thumb you described in the video.
@cbbuntz
9 жыл бұрын
I'm replying 5 months after your comment. Anyway, my understanding is that power is expressed as 10*log10(x) while voltage or current is 20*log10(x) because watts = volts * amps. So 2 v * 2 A = 4 W or 0.5 v * 0.5 A = 0.25 W If both volts and amps increase / decrease by the same proportion, it's equivalent to the squared difference in power and dBv and dBm will change by the same amount. Multiplying a logarithm by 2 is the same as squaring 10*log(x*x) = 10*log(x^2) = 20*log(x) Therefore -3 dBm is 0.5 mW and -6 dBv is 0.5 v
@rockydogsdad
8 жыл бұрын
Have used dBohms before. Since I=E/R, then in log format, dBuA=dBuV-dBohms. Used to calculate current when measuring voltage with a current probe - probe cana correction factor vs. frequenct in dBohms! Nice and easy.
@rockydogsdad
8 жыл бұрын
Sorry about the typos. The current probe has a correction factor in dBOhms.
@ShahidKhan-sm3rf
7 жыл бұрын
hahahhaahahahaha... very good way of delivering knowledge
@doodh_jalebi
12 жыл бұрын
Me Before watching this video: 10dB Me After watching this video: 120dB!
@1337flite
3 жыл бұрын
2:40 "... and really that is all there is to it..." . video length: 20:47. 18 minutes and 7 seconds of fluff, apparently. :-)
@L2Productionsau
9 жыл бұрын
Thank you so much for the video! you are definitely an aussie aren't you? haha
@varungopal6272
7 жыл бұрын
but why should he take 10×log for power and 20×log for voltage and current?
@FireicerCooper
7 жыл бұрын
Simply is P= IxV but P= V squared / R P= R X I squared hence why dB volts is 20Log... Because when you use Voltage and Resistance to calculate power you have to square the Voltage before dividing it by the resistance. So one should be able to see why 20 Log is used for Volts.
@jkbrown5496
6 жыл бұрын
There really is only one formula 10log(p2/p1). Power is v**2/R or I**2R. In common usage R will be the same in the measurement of p1 and P2 so cancel out if you substitute the voltage or current form of power. So you end up with 10log[v2/v1)**2] if using the voltage equivalence for power The log of a number raise to a power is equal to the exponent times the log of the number Hence, 10log[v2/v1)**2] = 10[2log(v2/v1) = 20 log(v2/v1) The 20log() for voltage and current are due to voltage or current being squared to get power. you could view them as 10Log(p2/p1) = 10[2Log[v2/v1) or 10[2Log[I2/I1) = 20Log(), assuming resistance is the same across measurements 1 and 2.
@electra
14 жыл бұрын
Great videos. Please continue to do these traditional electrical engineering topics/issues and ignore the people that request simpleton versions or projects and hacks. There's plenty of that junk on the internet already.
@drdave1947
Жыл бұрын
We need an engineer to invent a decibel-controlled TV so that programs don't try to damage my hearing with loudness, AND so I can hear the soft sounds. About 7.0 would be great, but it needs to be adjustable.
@stokes111111
6 жыл бұрын
awesome video and I love your energy, thanks for this!
@martinkuliza
Жыл бұрын
I asked my wife for a Cup of coffee. 6dB Down she offered to slap me 10dB Up :P
@AndresMilioto
11 жыл бұрын
I'm on the 4th year of engineering school (here on argentina the career is 5 years long), and I have to say you are totally ruining my education, because now all my teachers seem REALLY boring. THANK YOU!! YOUR BLOG IS THE BEST, I CAN'T GET ENOUGH OF THIS VIDEOS!!!
@scottpelletier1370
2 жыл бұрын
What are you working on now?
@AndresMilioto
2 жыл бұрын
@@scottpelletier1370 I ended up getting a PhD in Robotics. It was a wild 9 years lol
@scottpelletier1370
2 жыл бұрын
@@AndresMilioto haha that's awesome! Congrats and thanks for the quick reply.
@pearsgr
7 жыл бұрын
thanks can you add some details about decibels readings on a multimeter please
@marshallnmoonshine
4 жыл бұрын
My great great great great great great (plus however many more) grandfather invented logarithms. Dig your channel, man! Thanks!
@JoannaHammond
9 жыл бұрын
The only thing that drives me nuts about db's is.. Why the hell do we have two formulas!!!! When one would do.
@dh1ao
9 жыл бұрын
+Joanna Hammond voltage dB is derived from power db. P=U²/R. So if you compare to powervalues over the same resistor you get the ratio (u1)²/(U2)². So 10xlog((u1)²/(u2)²) = 10x2xlog(u1/u2) (because e.g. log(a⁵)=5xlog(a)) that's all
@kingsman428
3 жыл бұрын
My wife *"...What are you moaning about this dress was only 40dB dollars more than that scope you bought..."*
@fernandohood5542
4 жыл бұрын
Theory is nice. How do I design a 40 db op amp AT 1MHZ with 50khz bandwidth with low noise input.
@zanfr123
11 жыл бұрын
Thanks to this I finally understand (at my age lol) how dBs work and how they can come in handy.
@RecordingStudio9
9 жыл бұрын
Wish I had you as my electronics teacher some 30 years ago! I would have lived at TAFE!
@joiseystud
10 жыл бұрын
Actually if you're an engineer looking at a glass thats contains water to the halfway point, you would say "There is twice as much glass as we need"
@miki333sp
6 жыл бұрын
fucking love u man, u susccefully teached me in 20 minutes whole dB stuff, that teachers tried to teach me over 6 hours
@bp968
9 жыл бұрын
Interesting. I've always thought of dB's as a measurement of sound level. It's interesting in the gun world to see how confused people get when talking about dB sound levels. People see the sound level of a silenced/suppressed gunshot (136-138dB for a 5.56mm) and say "well that's not quiet, that's as loud as a jet engine!". Which is only partially true. The gunshot is an impulse sound and an extremely short one (microseconds I believe) while the jet or jackhammer is continuous. Once you see how the human ear "hears" you quickly grasp that the 136dB is actually pretty quiet. Especially when compared to the original sound level of 160-168dB!
@tushar8133
Жыл бұрын
9:11 - "It's less than the width of the one fibre on the tip of this pen" This shows the perspective of how an experienced person visualize 😊
@tomcass240
Ай бұрын
So if I buy an antenna and it says 3db gain, what is the "reference value" in that example?
@87knox
12 жыл бұрын
Decibels were originally designed for power, so the formula for power is 10*log(a/b). However, power is proportional to the square of voltage. Therefore, if you double the voltage, the power will quadruple. Based on the algebraic rules for logarithms, if you take that power of two out of the argument, it will multiply the result. 10x2=20, so the formula for voltage is 20log(a/b).
@jpmcbride
12 жыл бұрын
The 20log and 10log formulas really confuse people. Its easy to explain though ... First, the dB is defined in terms of power as dB = 10 log (P1/P2) If you want to solve for voltage, you substitute into the above formula P=V^2/R to get, dB = 10 log [(V1^2/R) / (V2^2/R)] Now cancelling the R's above gives us, dB = 10 log (V1/V2)^2, And the rules of logarithms let us move the 2 down like this, dB = (2) 10 log (V1/V2) which gives us our dB formula for voltage, dB = 20 log (V1/V2)
@PileOfEmptyTapes
13 жыл бұрын
Since it seems to be a common question: dBs in sound are easy. dB SPL (sound pressure level) is dB relative to 20 µPa, a value close to the mid-frequency human hearing threshold. (It's AC, so probably an RMS value.) Now sound pressure is analogous to voltage, and sound particle velocity relates to current in the same way. Hence, it's "voltage dBs". A microphone will usually have a spec'd sensitivity in dBV / 1 Pa = dBV / 94 dB SPL. This directly links the sonic to the electrical side.
@shodanxx
14 жыл бұрын
I think this is really confusing to sometime use 10 log and some other time 20 log I didn't really get the why of that when I learned ham radio I was told that 3 dB is double the power and that was correct and that 30 dB was 1000 time the power I wasn't told about using 20 dB for magnitudes so when someone whatever was 30 dB I though it was 1000 time more intense but if they were talking about a voltage or magnetic field strenght it was only 316 times more .. no wonder people are confused !!
@kchididdy
15 жыл бұрын
Correct me if I'm wrong Dave.... I generally don't like to memorize formulas. I would probably go one step further and state that power is proportional to the square of magnitude. In high school math, we learned that (assume log base 10): log (v^2) = 2 log(v). Since we are dealing with "deci" Bels, we multiply both sides by 10 to yield: 10 log (v^2) = 20 log (v). In other words, dB values are indeed ratios, but it's implied that the ratio is in terms of power/intensity.
@MauroTamm
11 жыл бұрын
its simple like that when u deal with nice numbers ... but it becomes hell if you have .. lets say 174.54 x the power of something. i wonder if u get kicked out... if you go to electronics shop... place 10 diodes on the counter and ask them to give you 15dB of those diodes :D
@RW1701
11 жыл бұрын
You're referencing to 1V, so the number of dB is the ratio between your voltage and your referance voltage. As your numbers are the same (both 1V) then the ratio is 1. log1 = 0, so dBV for 1V = 0dBV Yeah, this concept is fairly simple once you understand it, but really difficult to teach :/
@markuscwatson
6 жыл бұрын
Aaaaaaaaaaahhhhhh.... using the dB scale on a FT allows you to view small and large signals on the same scale: good for seeing the noise floor. I always set the scale to Linear because it’s easier to understand. Now I will keep this video in mind.
@hansen97124
6 жыл бұрын
Not crazy about this video. It would have been better if Dave would have mentioned a few things... First, dB is always a statement of the change in power. It so happens that 6 dB is twice the voltage, but the important part is that 6 dB is 4 times the power. I don't think he ever stated this. Again, dB is a statement of the change in power. This is important because people sometimes measure a voltage "gain" say, through a 1:4 transformer, without realizing that the power "gain" is unity (minus losses). Second, since he's taking the time to explain all of this, reviewing Logarithmic Math, even though it;s generally covered by Freshman level, would be helpful. Third, to say that when you are working with DBV, one must be working with the 20*Log formula as he does at 20:02, is misleading. Sure, you are referencing 1 volt as the starting point, but again, dB is still a statement of the power change. Here's the final exam: What happens to the student when he/she tries to measure the "dB gain" of a 1:4 transformer? Put 1 V on the input. Now express the change from input to output expressed in dB. Try it in dBV. Try it in dBm. I think you will see quickly why it is important to always think of dB in terms of a power ratio.
@fuahuahuatime5196
6 жыл бұрын
Do you mean literal power (P=IV), or the type of power you'd find in power and signal courses? Maybe power gain is unity, but that isn't true for voltage and currents I think.
@PileOfEmptyTapes
13 жыл бұрын
Now if you want something *hairy*, try calculating the voltage and power gain of a unity gain buffer (with an actual source and load). Hint: You can express both in dB, but the value will not be the same. Why?
@sonicelectronic7990
Жыл бұрын
Been "using" dBs for decades and never really understood. Now I get it! Thanks! P.S. I've always said the glass is both half full AND half empty, what does that make me?
@VilleWitt
Жыл бұрын
Bipolar?
@srira7910
Жыл бұрын
Wow, this was really helpful, great perspective. Gifted teacher.
@wilhelmderaufschlitzer8140
8 жыл бұрын
-6dB equal a half of a rabbit hahahhaa you're right.
@xoox870
5 жыл бұрын
The reason why voltage is 20 times the ratio compared to power which is 10 times the ratio; is because the derivative of V^2 (used to calculate power) is 2*V - - - there is significant confusion with dB, dBm, dBw, dBi, dBd, and others if you don't know the 'context of the application', especially with voltages or powers. 6dB is double for voltage , but 3dB is double for power !! it is better to use dBW or dBmW for watts and dBV or dBmV for volts to avoid confusion. - - - decades are relative to 10's of dBs not scales as mentioned. - - - negative decibels are simply the reciprocal of positive decibels. @ 19:45 he has it backwards !! - volts are a power since they are squared and watts are a magnitude since they are NOT squared. this is why for volts there is 20X the log since V^2 is used in power formulas. - - - FYI 555 timers are one of the worst crappy electronic parts there ever invented. - please research monostable multivibrators for much better parts ; at least they can produce a 50 % waveform; a 555 cannot since at 50% both comparators would trigger !!
@josenieves5038
3 жыл бұрын
Question -- Can you do a comparison of SPL meters like you did on the multimeters? Is a cheap meter reliable enough to an expensive meter? Certification standards? I've watched a few of your videos and always learn something. I really loved your Multimeter shootout and actually didn't watch it until after I purchased a Klein MM700 and CL700. I realized a year or so later I really wanted the CL800 for DC current (I had overlooked that difference) which I got and would have purchased originally if I watch your shootout.
@pvbinoyable
13 жыл бұрын
@yeoldeengineer the value will be same. for calculating power in decibel you have to use 10 log (P2/P1) and for voltage 20log(V2/V1) . you might have used same formula for both. thank you
@patrickwall144
7 жыл бұрын
Thanks. all I was looking for was what was being measured in respect dBm. After the last guys video what I had was 10log10 something over .001 = Powerin over Power out and he finally just gives the 6dB 20dB 30dB says thats what it works out to and informs you you understand dBM. I started out knowing the majority of it. found myself a little cobfused and simply wanted to know what I was measuring. I ended up knowing less than I did when I started. You answer the question in the first min. then bring some sanity and structure back to my thinking with the rest. Thank you.
@7urgan
4 жыл бұрын
magnificent old tutorial, but at 20:25 its = 6db_cup, and yea we are engineers ;)
@KostadinIVKostadinov
9 жыл бұрын
Water is closer related to power than voltage. Filling with water requires potential energy, which can be achieved by power (voltage and current over time). According to that, your glass is (approximately) only 3dB down! (discuss)
@sherifnegm9046
7 жыл бұрын
thanks so much. Your tutorials are very useful to high school physics students too xD
@fuahuahuatime5196
6 жыл бұрын
Lol. Doubt you'd learn this in high school physics. You don't even learn it in college physics.
@DasAntiNaziBroetchen
4 жыл бұрын
It's like you're whisper-screaming in this video.
@ddemon4406
11 ай бұрын
very helpful video. felt like you were going to poke my eye out with that marker.
@krish2nasa
8 жыл бұрын
Excellent explanation, Thanks Dave
@aceboogiebooyah4278
4 жыл бұрын
I hope this guy comes knocking on my door one day as a dB salesman, and I can thank him greatly for selling me on dB's long ago, and to sign me up for more! HaHA You rock guy! Power to the people!!! (dB's)
@josediaz85
6 жыл бұрын
Another engineering example: it is common practice to use Decibel scale to represent harmonics signals, for example in power quality when representing the fundamental voltage together with the harmonic content of a signal, normally the fundamental is much much bigger. Thank you Dave for your videos!!!
@plavix221
9 жыл бұрын
thanks. ONe could also use 10 to the power x or - x as a scale. But why make it easy. Because we think intuitively with logarithmic ratios and not orders of magnitudes. XD
@erroneous6447
11 жыл бұрын
I edited my original comment to avoid confusing people. But to answer you question plainly...yes, he is talking about the voltage gain.
@stevetobias4890
4 жыл бұрын
Thanks Dave, loved the explanation. Helped heaps mate! 👨🎓 I can't go by rule of thumb, half of it is amputated, lol
@fardellp
5 жыл бұрын
What an outstanding tutorial. I would say that Dave is unique in his ability to explain electronics. My only concern is for his health. He is so passionate about explaining concepts (especially BS) that I fear he might be heading for a stroke.
@tacettinozbolukozboluk
9 жыл бұрын
How can i calculate maximum distance of rf for example 433MHZ 5V 100mw maximum range of open area
@rockydogsdad
8 жыл бұрын
Different formula called the Friis equation. Forget the voltage, just use power. Depends on receiver sensitivity, (usually in uV, should convert to dBm in this case), and receiver and transmitter antenna gain, too. Will return path loss in dB.
@mikedemoore6670
7 жыл бұрын
Great Dave!!! Perhaps there would be more engineers around if we were taught by people like you?
@diogenes9991
5 жыл бұрын
It's easy to get the idea, but I love the way him explaining. Congratulations and Electronics for all!!!!!!!!
@funugger
8 жыл бұрын
So why does 6dB equal half? I've never heard that explained. Is this just something without a real reason?
@edgerrr
8 жыл бұрын
+Peter Anderson - When referring to voltage (and current), -6dB is the result of the equation shown at 3:05 when V1 (Vout) is half of V2 (Vin). If V1 (Vout) is twice V2 (Vin), the result is +6dB. When talking "Power", half and twice as much is -3dB and +3dB respectively.
@oobihdahboobeeboppah
12 жыл бұрын
Great tutorial on decibels for anyone getting started in technology; highly recommend this video for anyone studying for their Technician Amateur Radio license.
@johnmanzang7272
2 жыл бұрын
Thank you very much for a very good explanation!
@rarbiart
11 жыл бұрын
no, dB are not a complex thing, they are just rational logarithmic! ;-)
@goofyahhslimjackson1942
2 жыл бұрын
Take a shot everytime he says "db" Life insurance ad intensifies
@hintzofcolorconcepts
8 жыл бұрын
How do decibels of sound relate to decibels of electrical power? 10 log 20 log?
@rockydogsdad
8 жыл бұрын
10log
@williammann4485
4 жыл бұрын
This is straight-up patronising. Turned off after 1 minute
@hynekboruvka8346
6 жыл бұрын
Nicely explained, thanks a lot! Longer than other useless explanation videos, but short enough to be able to stay focused whole way.
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