stunningly stupid Electronics Design article

If there's enough current to keep the transistor turned on during the fall time, sure.

Cheers

Phil Hobbs

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Phil Hobbs
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I'll get you a P500 when the firmware is done. The output stage is one of the best things I've done.

The B+K 4003 fungen is nice, a classic analog generator with a built-in frequency counter. To change the frequency or amplitude, you just grab a knob and turn it.

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I don't use the sweep much, but sweep also makes calibratable period jitter, which can be useful.

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John Larkin         Highland Technology, Inc 
picosecond timing   precision measurement  
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John Larkin

Nope. I used to do some SSB (single side band) radio testing which required two tones and very low intermodulation distortion (IMD) between them in order to see the RF power amplifier IMD products on a spectrum analyzer. Audacity only generates one tone.

There are plenty of PC software tone generators that will generate two tones. The ones I like best are those that output each tone separately to the PC audio left and right channels. If I want low IMD, then I can easily filter harmonics and crud from the sine waves, and combine them externally with a resistive combiner to get a low IMD combined output. The programs that use the Windoze or sound card mixers tend to be (usable), but not as good. Favored program is Visual Analyzer: into a 16 or 24 bit sound card.

For single tone, and most everything else, it's whatever program I have on my PC or Android app on my smartphone or Chromebook. If I'm in my office or at home, whatever generator is on top of the test equipment pile.

I use Audacity for editing my keyboard synthesizer music and for format conversion.

Presumably, the author of the article had access to a computah, tablet, or smartphone when writing the article. With the wealth of software generators available, I'm really surprised that he would choose to use a YouTube 1Khz tone recording.

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Jeff Liebermann     jeffl@cruzio.com 
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Reply to
Jeff Liebermann

The 50 ohm load takes care of that. An R+L can be used too, to keep power down but drive a dinky hi-Z scope.

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John Larkin         Highland Technology, Inc 
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Reply to
John Larkin

Not true. Maybe one tone per track but you can have multiple tracks (don't know what the limit is).

Reply to
krw

Sadly for John Larkin's reputation, Paul Krugman isn't an idiot. Idiots don't get Nobel Prizes for Economics, not that the Nobel Prize for Economics is as impressive as the Nobel Prizes for sciences that have got a bit further.

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Bill Sloman, Sydney
Reply to
bill.sloman

Ok, you're right. I got it to generate two different tones by:

  1. Add a stereo track.
  2. Split the stereo track into two mono tracks.
  3. Select one track. Generate -> Tone -> Pick a freq.
  4. Select other track. Generate -> Tone -> Pick a different freq.
  5. Set levels. View -> Mixer Board.
  6. Play.

If I want to change the frequency, I have to the contents of one track, and add it back from scratch. Not exactly obvious or easy, but it does work. I think I'll stick with Visual Analyzer, which does it better and easier.

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Jeff Liebermann     jeffl@cruzio.com 
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Reply to
Jeff Liebermann

I look forward to ooh'ing and ahh'ing over it. :)

Cheers

Phil Hobbs

Reply to
pcdhobbs

It should be able to do time sweeps, which would be fun. And maybe calibrated jitter.

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John Larkin         Highland Technology, Inc 

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John Larkin

Sure, it may not be the best tool for every job but it does a lot of them. Having a different tool for each task is rather inefficient.

Reply to
krw

I beg to differ here. I don't like Swiss Army knife solutions and prefer a collection of small tools (as was the philosophy of early Unix). In duz-it-all conglomerated programs such as Audacity, there always seems to be one part that doesn't quite do what I want or how I want it to work. That forces me to decide whether I want to live with the problem, dump the entire conglomeration and find a better conglomeration, or hack my own with open source software. All of these choices are sub-optimum. However, if I had started with a collection of smaller programs, which do the few things I need quite well, I have a much better chance of getting them to do what I want in the manner in which I find most useful. I would prefer smaller and more modular tools, but Visual Analyzer is adequate for my purpose.

As for efficiency, I recently purchased a use multi-tool, a Leatherman Wave. It's a tool where I can carry every tool I might need to do repairs in one convenient package. So, I dumped my single blade pocket knife, pocket screwdriver, and small vice grip pliers, and replaced them with the Leatherman Wave. The problems arrived immediately, when I received a nasty bruise on my leg where I carried it in my pocket. It might have worn a hole in my pocket except that I ordered the belt clip option to wear it on my belt. That was better but was clumsy to remove from my belt and started to shred the lining of my jacket. When I tried to use one of the tools, I soon discovered that it was really awkward because everything was attached to everything else and got in the way of the other tools, just like in a duz-it-all program. I'll skip over cutting myself with the knife and breaking the tiny scissors. Within a week, I was back to my small tools approach of a single blade knife, vice grips, and pocket screwdriver.

Also on efficiency, I sometimes wonder about the efficiency of the latest fashion in urban assault vehicles as the crew cab, 4wd, full size bed, diesel powered, pickup truck. It's certainly a conglomeration of everything one could conceivably want in a work vehicle. However, it also seems a bit inefficient to drag everything along for the ride, kinda like that multi-tool, Swiss Army knife, and duz-it-all software.

Think small.

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Jeff Liebermann     jeffl@cruzio.com 
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Jeff Liebermann

If I do a task every day, I'll likely have a tool optimized for that task. If I do a task once a year, no, I'll find some other tool in my toolbox that will also this once-a-year task.

How many times do would you really use a Leatherman if you had one with you. I know I wouldn't at all. I don't even carry a knife - very little use for it, compared to the bother of the lump in my pocket.

Your wording shows your contempt for "urban assault pickup trucks". The rest of the words are superfluous.

Think happy. It's not always in small "packages" but if that's all you have...

Reply to
krw

I almost always have my original leatherman in my pocket. ~4 x 1 x 1/2" a little smaller would be OK.. all the new ones are bigger. (sigh)

George H.

Reply to
George Herold

a
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these are smaller, 3.25" and 2.25"

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Reply to
Lasse Langwadt Christensen

Welcome to geek or nerd high fashion. The original Wave is a heavy beast at 9 oz (255 g). When I took it apart for cleaning (it was filthy when I bought it), I weighed just the frame and other non-functional hardware at about 140 grams or 55% of the total weight. In other words, 55% of the tool was useless dead weight. Newer tools use a better design but they're still quite heavy. Leatherman makes smaller tools, but this one was used, available, and cheap, so I bought it.

This is what I usually carry around with me (unless I'm doing exercise or need to wear a suit): The idea was to get rid of some of the pocket protector tools, knife, and channel locks. It didn't work.

Someone is sure to ask why two sets of keys. I got tired of locking myself out of my car, house, office, and having some visitor drive off with the bathroom key.

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Jeff Liebermann     jeffl@cruzio.com 
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Jeff Liebermann

I have three or four Juice XE6es, which I quite like.

Cheers

Phil Hobbs

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Dr Philip C D Hobbs 
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Phil Hobbs

The Juice XE6 is lighter, but it's not what I need or want.

All the Leatherman products are great tools but all have the same fundamental problem. They all try to satisfy the widest possible range of users and uses, resulting in quite a bit of useless bulk and weight. For example, do I really need to carry a cork screw as found on the Juice XE6? I've been doing repairs and using pocket tools long enough to know what I need. Basically, the small tools should be removable and the large tools (knife, pliers, cutter) need to have a strong handle for maximum leverage. The pliers should be locking like vice grips. The cutter should have inserts for stripping various diameter wires. None of the multitool designs I've seen do it this way, although some come close.

I'm resisting the temptation to build my own multitool by tearing apart a Leatherman for the blades and tools, and reassembling them on a different frame in a manner I think might be useful. There is a sub-culture appearing on YouTube that "mods" Leatherman tools to produce more interesting combinations. Locally, the university has a limit on the length of pocket knife blades that can be carried on campus, which has resulted in a lucurative Leatherman blade shortening service. There's plenty of opportunity to be creative.

I now have access to a CNC mill and have scribbled some ideas that might be worth building. However, the machine is now rather busy making money and I have a grow list of projects that are not getting done. Maybe someone will accidentally do it right so I can buy one.

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Jeff Liebermann     jeffl@cruzio.com 
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Reply to
Jeff Liebermann

How about adding a zip gun for those tough neighbourhoods? ;-)

The football hooligans in the UK came up with a short bladed knife that would inflict scars that never heal up properly. They used a Stanley knife with two blades inserted where there's normally just the one, and separated them a few millimeters by jamming a broken off matchstick between them. So it's not all about length.

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Reply to
Cursitor Doom

lol people in the UK pay to watch some guys kick a ball and get stabbed while they're at it

Reply to
bitrex

It's a tool, not a weapon. I guess any tool could be used as a weapon, but I wouldn't design it that way.

Was that invented to replace the zombie knives after they were banned in UK?

I use the same tool to make long narrow cuts in PCB material for making circuit boards. A matchstick is too thick, but a trimmed zip tie works nicely. Patent pending.

I have a number of different Stanley utility knives (don't ask why): Only a few are wide or sloppy enough to fit more than one blade at a time. I know because I've tried them all.

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Jeff Liebermann     jeffl@cruzio.com 
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Jeff Liebermann

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