Are consumer electronics starting to become all alike?
Do you have the impression that many consumer electronics are becoming different forms of the same thing? Examples.
- Computers (desktops, laptops) are being replaced by tablets.
- Televisions are becoming "smart TVs" - another name for very large tablets
- Phones - just a small tablet
- GPS units - are just phones with GPS chips
- Still photo cameras and video cameras - just phones
- MP3 players/CD players. and radios - use your phone
The only consumer electronics that haven't changed are stereo amplifiers and big speakers - mind you, even those are being replaced by small cute mp3 speakers and ultra-expensive docking stations (that don't sound nearly as good as a decent amp and speakers).
Question answered by email@example.com
If one judges a book by its cover then yes. Beneath the consumer devices, different technology drives flat screens, plasma which is powered by gases in the screen. Beautiful while it lasts, but once the gases run out of their properties they cannot be fixed. The plasma tv is disposable. Therefore LCD/LED combination is best. Flat screens look a like but they have different blood and bones so to speak. Tablets are separated by the agility of the processor. Kindle isn't as talented as Apple's iPad because the processor isn't even close. Samsung's software isn't as seamless and intuitive as Apple's though Samsung's processors are up there. I point these things out because we are in an age that the consumer has to give up on brand name as the indicator of better and best. We have know choice but to better understand how they work, then clarify the percent of improvement for the spend. I hope this helps.
Television broadcasting power?
From what understand, vhf band transmission is line of sight, meaning the height the antenna is placed above the ground is more important than the wattage of the rf amp.
I guess what I am wondering is, what is the reason that television stations use amplifiers in access of 50kw?
Why is it that a 1kw could not perform as well, and how much of a difference does amplifier power make?
Cb radios make it halfway across the country on just a couple watts, do television signals need more power because they have wider frequency ranges?
Also, would a low definition black and white picture require less power than modern color analogue?
Question answered by Bob D1
Those are some very good questions and ones that most technical broadcast people just take for granted.
Anything above about 100 MHz is considered "line of sight" transmission because transmissions above 100 MHz do not reflect off the ionosphere all that well, and tend to pass right on through it to outer-space. While it is important for good TV reception to have an adequately designed antenna as high as possible, RF power output at the transmitter is important too. RF power level wise, depends a great deal on where the transmitter is located with respect to the viewers, and the directifity and gain of the antenna used. RF signal strength radiated from the antenna falls off in intensity with the square of the distance from the antenna, inverse square law. A 1000 watt RF signal at the transmitting antenna may result in a receiving signal of only a few milliwatts or even microwatts at a distance of only a few miles. So the more RF power output at the broadcasting antenna, the stronger will be the received signal for any given distance.
CB radio is much lower in frequency than say VHF TV broadcasting, and lower frequencies tend to hug the earth's surface more, as well as they tend to bounce back to earth off the upper atmosphere, as skip waves. You do have a good point in that "bandwidth" is related to the amount of RF power output required to communicate information over any given distance. CB radio has a bandwidth of around 10 KHz and most of its RF power is focused in that small bandwidth. Television, on the other hand, operates at a far higher frequency (shorter operating range) with a far greater bandwidth (4.5 MHz to 6.0 MHz) and emits a much more complex signal. TV signals include AM video, FM sound, color burst, and various timing signal information; thus, the signal complexity and large bandwidth demands more operating power from the transmitter. Something else to take note of: a typical TV antenna is maybe 2 or 3 feet wide and 3 or 4 feet long compared to a CB radio antenna of between 9 to 18 feet tall and 9 to 18 feet wide, a far difference is dimensions. TV stations operating at or just below 30 MHz would be able to reach out over greater distances but would require its customers to put huge antennas on their homes and businesses. The bandwidth would be exceedingly large as well, taking up a spectrum of between 25 and 30 MHz. It would be very wasteful.
Yes, you are right. To broadcast a purely black and white TV signal for a given distance and received signal voltage level, would be less than for a color TV signal emitted from the same distance. Extra signal power goes into adding color information to the composite video, such as the 3.58 MHz color burst reference pulses. Because black & white TV doesn't require as large a bandwidth as does color broadcasting, it can be communicated over a slightly greater distance for the same amount of RF power output..
See: Explain that Stuff!
See: Elements of a Television System
Basic TELEVISION and VIDEO SYSTEMS: fifth edition
by Bernard Grob
I have a ATSC tuner. Do I need a receiver? Can I just use an antenna?
Question answered by percival.sweetwater
Just the tuner? Nothing else?
In audio, you need a tuner to pull in radio stations. But you still need an amplifier to feed the radio station to your speakers. Some (most) stereos include a tuner and amp, all in one, called a receiver.
In video, you need a tuner to pull in TV stations. But you still need a monitor to display those stations. Some (most) units include a tuner and monitor, all in one, called a television set.
If you're talking about the receivers provided by a cable company or satellite company, those are just alternatives to using an antenna. You can use THEIR antenna (through their receiver) and gets lots more channels for a price, or you can use your own antenna for only the cost of installation.
Who was the first punk?
Question answered by Bad Brain Punk
I would say Link Wray. He invented the power chord, as I recall, and dressed in black leather and sun glasses like the Ramones ... except he did it in the 1950's. I think I once read that he punched holes in his amp so that the sound would be more distorted. His 1959 instrumental 'Rumble' was actually banned by some radio stations due to its aggressive sound.
IMHO, you can draw a (slightly crooked) line from his music through to the NYC scene (i.e. NYC Bowery bands: New York Dolls, Patti Smith, Talking Heads, Television, Blondie, Heartbreakers, the Cramps, etc.) that spawned the Ramones. The Pistols credit Johnny Rotten with creating their attitude and image, and he is the one who put punk on the map, but they were inspired by the Ramones.
Following that family tree backwards leads to Link Wray and the Wraymen. His music still crops up on occasion, i.e 'The Wild One' was used on the soundtrack of Lock, Stock, and Two Smoking Barrels.
For a longer answer on my take on the history of punk, see this one:
And for the first punk record, see this one:
In regards to april9rockstar, below, Legs McNeil was one of the founders of Punk magazine, but the term was used earlier to describe the music of assorted bands, and perhaps used first in reference to ? and the Mysterians. See: http://en.wikipedia.org/wiki/Punk_rock
Rage Against the Machine - Sleep in Fire?
whats the story behind this, I know they played on wall st.
Question answered by zeleftikam
The song contains lyrics about greed, such as the conquest of Native Americans and U.S. Slavery in the 1800s as well as criticism of actions taken by the US government in wartime, including the bombing of Hiroshima and the use of Agent Orange in the Vietnam War. At the end of the song, there is some sound from a Korean radio station that guitarist Tom Morello picked up on his amp.
The music video for the song was directed by Michael Moore and featured the band playing in front of the New York Stock Exchange, along with scenes from a mock-up of the popular television game show Who Wants to Be a Millionaire which is satirically named "Who Wants to Be Filthy Fucking Rich". During the filming of the video, Moore was detained by police for an hour, and the NYSE closed its doors during mid-day trading because of the crowds that gathered to watch the filming. Quoted at the end of the song is Republican politician Gary Bauer stating that, "a band called 'The Machine Rages On' - er - 'Rage Against the Machine', that band is anti-family and it's pro-terrorist," following an incident outside of fellow Republican Alan Keyes' 2000 primary campaign town hall event, where Keyes jumped into a mosh pit that was playing the music of Rage Against the Machine. There is briefly at the end of the music video, possibly a single frame where a difficult-to-identify figure emerges. Actor Garrett Wang is briefly seen in the video enjoying the music.
The video was nominated at the MTV Video Music Awards for Best Rock Video but lost to Limp Bizkit's "Break Stuff".
What is the best size and quality subwoofer(s)/amplifier for me?
I drive a honda civic
-Looking to spend about $450-550 for some high-quality, loud, thunderous boom with good sound quality (as to say not to have the boom completely drown out the singing/other instruments)
-I will be playing rock as well as rap music
What size sub should I get? should i get 2? specifications?
What amplifier specifications will I need to run that or those subs?
I also hear the term 'headunit' thrown out a lot in my research thus far, will I need one of these? What specifications for that?
Anything else I'm forgetting? I have 2 pioneer 6 inch 30w speakers in the driver and passanger door, as well as two speakers(w.e is in the back of cars, subs?) that say NOM 30 MAX 60) if any of that matters
Will I need to get new speakers to go with he subs and amp?
10 points and my eternal gratitude for the best answer!! Thank you so much
the back speakers are also pioneer. i am not concerned with the brand of sub/amp/speaker as much as the specifications (RMS, ohms or w.e and size) since I will use my consumer reports subscription to pick out the brand
Question answered by jon
ill give you what i can, but you really need to just do some reading on crutchfield or another car audio site.
a head unit is the actual stereo that is installed in the dashboard, it plays CDs, radio stations, iPods, etc. and provides power to the speakers. if you have a stock stereo you can buy a Scosche SLC-4 to wire subs because you NEED rca outputs to hook up a subwoofer amplifier.
a good setup for your application would be a pair of 10s. and i would recomend the Kicker Comp 10s from 2007, alot of places have them on sale right now because kicker released a 2010 model. this is not to say that the 2007 ones are used, just think of it as a television, the old ones go on sale when a new one comes out.
to power those kickers (they are single voice coil, 4 ohm subwoofers that take 150w rms) you will need a two channel amplifier, like the PowerAcoustik BAMF 800/2
to wire up the system you will need a 4 gauge wire kit, these are pretty cheap and a kit will include a power wire to your battery, a ground wire to your car, RCA cables to your SLC-4 adapter, and a remote wire to a switch or to your factory stereo.
crutchfield.com has some great articles and research for all the installation stuff, but if you dont have a clue what youre doing, i would suggest professional installation.
one of the cheapest places to buy car audio is SonicElectronix.com and DealerCostCarAudio.com
What is the meaning of heterodying? What is the function of an RF tuner, Mixer and the local oscillater in the TV receiver section?
Please please help me and also mention the site if referred! I need the info for my class seminar!
Question answered by Bony
** Heterodyning is the mixing of two signals to produce new sum and difference frequencies.
The RF amp takes the input signal at the TV input and amplifies or increases its amplitude.
Tuned circuits here form a simple band pass filter to only allow the required frequencies through.
The local oscillator is a variable frequency oscillator, with a frequency that is related to the RF frequency. This we will see later.
The application of these two signals to the mixer produces sum and difference frequencies at the
mixer output, as well as the original two input frequencies. This is hetrodyning.
For a television, or radio, to be able to select the frequency of one station from the several others
presenting their signals to the aerial or antenna, around five to seven tuned circuits are required.
This presents two problems;
1) To amplify the < mV signal at the aerial, to volts required for the detector, requires an amplification of around 1,000 to 10,000. Risk of feed back a this high gain is likely if the aerial RF frequency
was so amplified at such high gain.
2) Its a simple enough matter tune five to seven stages to ONE frequency, but as we change channel
all these tuned circuits would require re tuning, this would be a difficult tracking operation.
Hetrodying solves both these difficulties, by dividing the amplification over two frequencies.
Firstly amplify at RF and secondly at a lower frequency called IF or intermediate frequency.
The trick is that by keeping a fixed difference between the RF and the Local Oscillator, LO frequencies,
the the IF frequency will always be the same, for TV the IF usually covers around 30MHz to 40MHz.
For FM radio 10.7MHz, for AM radio 455 to 470kHZ IF's.
Two ways to use Hetrodyning;
RF - LO = IF Examples 670MHz - 631MHz = 39MHz IF, 780MHz - 741MHz = 39MHz.
To tune to 670MHz Channel, set LO to 631MHz the IF will be 39MHz
To tune to 780MHz Channel, set LO to 741MHz the IF will be 39MHz
this is repeated for each tuned channel, and IMPORTANTLY NOTE IF will always be 39MHz!
THe LO is always the IF BELOW the RF.
At the mixer output several frequencies are available, but here we chose to select or tune the difference , RF - LO, the others do not get through the IF amplifier.
This allows FIXED tuning for all stages in the IF part of the TV signal amplification. Easy, no problem.
The undesired feedback due to high amplification at a single frequency, has been solved. Any IF getting back to an RF amplification stage will be rejected as its not in the RF bandwidth. Good.
The task reduces to, tuning only the RF for the required TV channel, and tuning the LO to always be
39MHz lower than the TV channel frequency. This will give a stable, relatively easily aligned circuit.
Occasionally, ( for radio) the LO - RF = IF will be used. Here the LO is always the IF ABOVE the RF
Most Mixers share a common transistor which also acts as LO. There is no separate stage.
Hope this helps. Please request clarification if required.