I made that mistake once, assuming that an ac-coupled emitter follower would drive a speaker. Of course, I was 11 years old.
-- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
That's Winfield's fault. Since AoE appeared many moons ago, that had most tricks of the trade in there that engineers usually need.
I am wondering how some of the newspapers with more class do it. I had the Wall Street Journal for a while and now the Financial Times. Both contain very little advertising but excellent journalistic work, and tons of it. It usually takes me more than 1h to read through at night,
2-3h for the weekend editions. They seem to struggle much less than local papers (I abandoned ours after decades because of excessive political slant).-- Regards, Joerg http://www.analogconsultants.com/
Or perhaps only one was able to dumb down his explanation to the point where John Larkin could follow it.
-- Bill Sloman, Sydney
Do you mean this comment? In addition, for the input stimulus to the circuits, a 1-kHz waveform will be used which will be generated from YouTube and applied to the circuit through an AUX cable breakout circuit.
I don't believe he intended that sentence to be in the article. The LTSpice schematic shows what looks like a proper sine wave generator so he didn't such a generator. I would suspect that the YouTube thing was some idea that he was playing with while throwing together the article, and simply forgot to delete it when it wasn't used: Why he needed .TRAN 10m, which does a transient analysis, and why he had both 10K loads connected at the same time (instead of one at a time for common emitter and emitter follower models), is unknown.
I skimmed through some of the other ED articles by the author: and found them to be somewhat better written than this mess. However, most of the other articles are short technology surveys and short applications articles, and are not about circuit design. While I don't particularly like the other articles, they are adequate for giving someone a quick look at some new or emerging technology, without slogging through data sheets and research reports. His articles are also top heavy with large photographs, but that's also excusable as such photos often convey more basic information than the accompanying text.
I have no idea what actually went wrong. My guess(tm) is he may have wandered outside of his area of expertise to produce something printable in haste.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
I think he really loaded a sine wave from Youtube.
Of course, he had to do his testing quickly, because the tone only lasts an hour.
-- John Larkin Highland Technology, Inc lunatic fringe electronics
Egads, perhaps you're right. I didn't know that 1KHz tone "video" was available on YouTube. I guess(tm) he doesn't own an audio or function generator. There are tone generators available as web apps, as Android apps, and as a Windoze/Mac/Linux downloadable program, but he uses a YouTube recording? Yech. Most of the software oscillosope programs that I use also include a software function generator. Perhaps he uses his computer as audio test equipment? However, that would not explain him using a YouTube tone generator.
Much as I like to assume that someone is innocent before I unleash my wrath, methinks I may have been a little too generous this time.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
The folks who solicit this kind of content get ticked if you use too many words and not enough pictures. They have their read-time targets in mind and too many words tends to make short Internet attention-spans close the window which is bad for earning Adsense revenue
"Content" nowadays tends to giant artistic fonts and pictures to fill up square feet of magazine space.
Speaking of pictures, there ought to be conventions/laws about identifying edited pictures and artists' conceptions.
Even NASA is bad about this.
I suggest some distinct icon in the lower-right of fake images.
-- John Larkin Highland Technology, Inc lunatic fringe electronics
it may be weird but it doesn't invalidate anything.
NT
Why? I don't drive speakers with them, obviously, but they're dead useful for lots of things.
Cheers
Phil Hobbs
Doesn't everyone use Audacity for this sort of thing?
Some tech dudez I know enjoyed having a laugh at this old Paul Krugman piece about how the Internet wouldn't be as big a deal as it was made out to be:
"As the rate of technological change in computing slows, the number of jobs for IT specialists will decelerate, then actually turn down; ten years from now, the phrase information economy will sound silly."
"It is difficult to make predictions, especially about the future."
That goes double for idiots like Paul Krugman.
-- John Larkin Highland Technology, Inc lunatic fringe electronics
The phrase "information economy" did peak in popularity in 2004 as the graph shows, never to return. If you account for all the employee hours that have been wasted on e.g. social media vs. the money the Internet has made for tech companies in the social media business it's probably about break even. The fax machine by comparison was undoubtedly a net win.
the bare-bones resistor-loaded one isn't too hot, usually when you build a current amplifier with a low output impedance you like want it to actually move current. which the resistor-loaded one can't really do very well for large signals. Like that floating inductor Bob Pease sketched up that's equivalent to 1 Henry but can only push microamperes like why, what's the point.
An extra transistor or two makes it a lot better at very little cost!
Better for many purposes, sure, but not all. Followers are good for driving later stages, Gilbert cells, and such stuff. I'd be unlikely to drive a connector with one.
Cheers
Phil Hobbs
Boggle!
I favour Daqarta - although the full version does a lot more than that but the signal generator part is free gratis and for nothing forever.
It is almost perfect for much simple audio stuff and demos.
Audacity is more useful for editing audio streams. YMMV
-- Regards, Martin Brown
I use a B+K function generator.
-- John Larkin Highland Technology, Inc lunatic fringe electronics
Followers are great for driving connectors, especially for positive pulses, like from photodiodes looking at lasers. A lot cheaper than fast opamps.
-- John Larkin Highland Technology, Inc lunatic fringe electronics
I generally use an HP 3325A or a Highland P400. ;)
Cheers
Phil Hobbs
-- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net https://hobbs-eo.com
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