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Big scope

Discussion in 'Electronic Design' started by Tim Williams, Jun 30, 2013.

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  1. Tim Williams

    Tim Williams Guest

    I thought this was amusing.
    http://seventransistorlabs.com/Images/ScopeBig.jpg
    The arbitrary difficulty was connecting the apparently ancient DE-9 VGA to
    the "modern" DE-15 style. Nothing hard.

    Few scopes have video output these days that I can recall (do any even
    offer DVI or HDMI?).

    I think it's funny that Tek put video only on the green channel (or at
    least, predominantly so). They could've easily driven all three together,
    for a better-visibility white.

    Tim
     
  2. Nico Coesel

    Nico Coesel Guest

    The photo is off. Look how purple that white (?) wall is. I have two
    TDS scopes and they output in b&w or color. Recently I had to do some
    measurements in my garden (some test setups won't fit in my office). I
    put a large monitor on top of the scope so I could read it from
    several yards/meters.
     
  3. What if you tie all three, RGB, together?

    The VGA appear to be training related.

    Cheers
     
  4. Joerg

    Joerg Guest

    That is so yesterday :)

    My (now several years old) Instek GDS-2204 can pipe out to a PC, live,
    and then I can render the scope output in almost any size I want. Since
    I need 1.5x glasses to read instruments but need 5x or so to solder
    this 0402 and 0201 SMT stuff this is very useful. I display the scope
    live on a computer which shows it at least 4x larger. That I can see
    without any glasses and I can simply peak past my 3x glasses or the 5x
    Donegan visor.

    A client's engineer mounted a 55" big screen TV. I haven't gone that far
    yet.
     
  5. Tim Williams

    Tim Williams Guest

    Yes, I did some white correction for the tungsten lighting in here, the
    green doesn't look right either.

    Since tomatoes don't produce much of a signal, might I guess this was an
    EMC related lash-up? (Who needs an anechoic chamber, eliminate the
    'chamber' and there's nothing to echo!)

    Tim
     
  6. Joerg

    Joerg Guest


    Sure, we have one at church but they make too much of a racket and are
    bulky.

    An MS OS in a scope? No way. I had the "pleasure" to use numerous
    Windows-based scopes over the years and now I am 100% positive that I
    don't want one.


    It is, I do all my design work on this PC via a 27" monitor with
    1920*1080 dots.


    Well, I'd rather buy a 55" TV for $1k or so and donate the other $32,000
    to a good cause.

    I prefer PCs and LAN/USB. Keeps it simple, and small.
    Personally I think that's overkill. I am completely happy with 1920*1080.
     
  7. Joerg

    Joerg Guest

    If they must have an OS I prefer a real RTOS.

    Even if I liked them, they are too big for my work space. The Veho USB
    microscope is great. 20x might seem much but once you are down to 0201
    or 01005 it's needed. For brick-sized stuff such as 0402 I use a Donegan 5x.
     
  8. Nico Coesel

    Nico Coesel Guest

    Somehow close. I had to do some testing with ultrasonic gear I
    designed. Its easier to test without echos from the walls and stuff in
    a room :)
     
  9. Tim Williams

    Tim Williams Guest

    They can pry my Trinitron out of my cold, dead hands. :) I can't stand
    using under 1200 vertical height anymore. I can *just* maximize a
    document, full page, and eliminate vertical scrolling at 1200. At 1080,
    it's just barely too little resolution to comfortably read: not enough
    pixels per character. That, and the color -- you have to be perfectly
    centered in front of an LCD to get the right colors, and even then, the
    edges are at enough of an angle (especially on big panels) that you get a
    halo effect. Eugh, no good for drawing.

    My laptop has a 15" or so 1920x1200, which is small, but just as legible
    at lap distance as my 19" 1600x1200 at desk distance.

    What I hate the most about 1920 x 1080 is, it's too short to view a
    document full height -- so, you might say, turn it sideways, most panels
    support rotated format -- ah, well then it's too narrow, plus you're
    trying to scan up and down a huge height, which is an eye and neck strain,
    plus the halo effect is more pronounced: the top, middle and bottom of a
    page don't look the same.

    I should snag a 2048x1536 Trinitron some day. LCDs go up to that
    nowadays, but they aren't nearly as cheap as the glut of consumer HDTV
    panels. Or if they are, they're full of dead pixels (something a CRT will
    never do :) ).

    Tim
     
  10. Fred Abse

    Fred Abse Guest

    You and me, both. Its getting to the point where you can't take a dump
    without Microsoft products.
     
  11. Joerg

    Joerg Guest

    That's indeed a nice little machine. However, it would have to go on the
    opposite side of the lab bench where there are no communications
    connections, certainly not the bazillion USB and RS232 links to lab
    equipment.


    My scope does all that with an RTOS. It does not need a computer, the PC
    is optional and only there to provide a larger display, direct Excel
    linking, et cetera.

    There are many uC-based RTOS'es, and then there is also QNX which in my
    experience is the best OS ever written for a PC. I could not make it
    crash in almost a year, and I am pretty good at crashing software or an
    OS during the "Joerg test". At Endosonics there was once a big
    ultrasound machine with a blue screen. Someone asked what happened to
    it. "Oh, that one has been joerged". I was the ultimate endurance test
    for systems at times. The first thing I usually do when confronted with
    a new design is to rock the circuit breaker back and forth a few times.
    That alone sends a lot of stuff back to the drawing board.

    Most things can be brought to the LAN. Heck, even my multimeter can hop
    onto the LAN and probably even be a "web site". So IMHO that should be
    the standard. USB for smaller more local stuff.


    If everyone was like me almost the complete automotive industry on the
    planet would already have disappeared. But I am not the worst case. The
    worst case was an elderly lady who bought a British sports car in 1961,
    used. Still looked like 1961. A few years ago she said that the car will
    likely survive her. That ought to be Detroit's nightmare.


    Nowadays the buzzwords would be cool or sizzling.


    But then you get guys like me who do not pay attention to advertizing.

    So how about my Boonton megacycle meter? :)

    http://www.ohio.edu/people/postr/bapix/Dip_59.htm
     
  12. whit3rd

    whit3rd Guest

    If this were a CRT, the monochrome image would be high quality (no dots) compared
    to a color image. A hypothetical color CRT has convergence issues, white traces will be
    rendered as RED plus GREEN plus BLUE curves, not necessarily all on top
    of each other.
     
  13. Tim Williams

    Tim Williams Guest

    Since the scan rate is so low and chunky at that resolution, you can see
    the separate scan lines up close; I didn't notice any convergence, but
    with green dominant or alone, obviously I wouldn't expect to (even at
    1600x1200 I only see the narest hint of divergence in one corner :) ).

    It's certainly not an LCD with big blocks for pixels (or better/worse yet,
    interpolated pixels), although that's probably not a bad idea -- a mono
    LCD would work as well as a CRT here; if I could even find a native
    640x480 resolution panel, it would be more crisp than the CRT.

    Tim
     
  14. Charlie E.

    Charlie E. Guest

    Actually, the new Sony 80" 4K HDTV is only $25K!

    (Just priced one, for fun, for a client!)

    Charlie
     
  15. Joerg

    Joerg Guest


    And then send a photo to my clients, with me on the couch :)


    It's the equipment. For example, the old logic analyzer has a very small
    CRT but one can use RS232. Goes into PC, PC display pics -> bingo.

    Today in the pool I had the idea of projecting a pic there, have a small
    margarita mixer on the pool deck, and float around in the water. My wife
    thought that would be decadent :)

    I really don't trust Windows when it comes to realtime.

    My experience with NI is that everything will cost at least $500. So
    I've largely stayed away from them.

    Well, I prefer something that's already natively capable of realtime.
    Such as QNX.

    I priced it out 15 years ago and licensing was quite favorable. Of
    course, there wasn't anything else comparable out there and as far as I
    can see there still isn't.

    "Overheated and not survived" clearly points to serious design flaws. If
    there is a chance of overheating there should always be temp sense and
    graceful shutdown.

    Those are the people you want in quality control :)

    I have a similar trait: Worked in medical ultrasound much of my life but
    I am one of the worst when it comes to ultrasound penetration and
    visibility.

    Too late. This has already been invented and usually comes in the form
    of toner and ink cartridges.
    You'd have to watch a great deal of TV to be exposed to subliminal
    advertizing. And there is the first problem marketeers have in our case.
    We have no cable or dish. Only an antenna and since that dreaded DTV was
    made law, reception falls apart so often that what little TV consumption
    is left has shrunk to a minimum. So the drill is:

    Tape old movies we like, repeat recording as often as needed until you
    luck out and the station won't pixelate out in the middle of it, then
    watch it some time later while skipping all ads via the FFW button.

    TV stations have shot themselves in the foot by two mistakes:

    a. Agreeing to have a working system replaced by a flakey one with
    sub-par RF path error tolerance.

    b. Giving up precious VHF space for less lucrative UHF space. That one
    I'll never understand. It has resulted in numerous stations not reaching
    suburbia anymore. Suburbia -> people with discretionary dough -> no
    longer reached -> drop in ad viewer number -> drop in ad revenue.

    Well, yeah, but only the good ones stick. Volkswagen marketing is
    exceptionally bright there. But will it result in increased sales? Not
    with me and my wife. Or take the repetitive slogan everyone knows: "If
    it fits, it ships". So I took a peek, saw that the prices aren't
    favorable, and to this day I still pack my own box and ship for a buck
    or two less. Sometimes the difference is well over $5.

    Or should work. They fail to work with many people who have lots of
    discretionary income. For example, you can't win much if you convince
    people who live on food stamps.


    I have one, a HD-1250, probably the same one you have. But those easily
    go *PHUT* in a high energy system.


    Au contraire. I had cases where people mumbled things like "That looks
    like voodoo" or "Now he's really off his rocker". Then at lunchtime I
    announced the problem to be found and some jaws dropped.


    In engineering? Who cares?


    No, because it frequently found stuff that their fancy schmantzy $10k+
    analyzer simply did not see.

    They often don't. Classic real-life example: I was called out to a
    client who had internal noise issues in a high-sensitivity chemical
    analysis machine they just developed. I dreaded it because it meant at
    least 3h each way on the freeways, can't fly there plus I needed to
    schlepp tons of gear. And my lower back doesn't like loading all that.
    So I got there, they had a luxurious Stanford Research analyzer set up,
    looked and looked and looked, couldn't find a thing. "Must be software,
    but the guys said it's impossible because the noise is clearly in the
    rwa data". So I tried. Shut the SRS analyzer down within 10 minutes.
    Pulled a laptop and a fairly ugly contraption out of my stuff, people
    cracked jokes about it. By early afternoon we had it, fan-blade induced
    noise that triggered air flow pulsing near a cap which in turn created
    wee microphonics. I showed them a fairly well distinguished 7-8Hz peak
    that was not very stable. On the SRS there was ... nothing. "No, you've
    got to be kidding, that's an artifact or something". Slowed the fan down
    with the palm of my hand, peak moved towards 4Hz. "I'll be darn!"

    Even many boat anchors have never been reached in performance by
    "modern" gear. One is the HP-3577 network analyzer. Same with the
    HP-3585 baseband analyzer. Or the Tek 2565 scopes. And on and on. So if
    you face a difficult analog job chances are that you won't be able to
    deliver your best performance if you only have "modern" gear.
     
  16. Joerg

    Joerg Guest

    I have no idea. It is in wide use but not in consumer applications.
    Well, except for smart phones.

    When we made our decision for QNX and against Windows CE in the 90's the
    reasons were crystal-clear. The QNX support team came across as vastly
    more knowledgeable and the license fees were very modest. Open source
    was not an option because this was med tech where you need 100%
    trackability.


    We were quoted way lower in 1997. $350 is a show stopper for just about
    any product.
    But still, nothing is supposed to die in here. If it does -> back to the
    drawing board. It's the same with automotive, if the water-cooling
    system fails because a hose burst that is not supposed to take out the
    pricey electronics.

    I usually try not to be but that seems to have no impact on the huge
    ultrasound signal losses in my body.


    I sure hope not.
    Ok, but if they worked, why is it that I pretty much never buy any
    products from ads? When I need something I browse for it, but only then.
    Maybe us guys are wired differently than women but I have never felt the
    urge to absolutely have to have something, or even go on a shopping tour
    with no particular needs.

    [...]
     
  17. Tim Williams

    Tim Williams Guest

    The perfect companion for a $50k scope! (you know, the kind with Windows
    :p )

    Tim
     
  18. Jasen Betts

    Jasen Betts Guest

    huh?
    By "trackability" do you mean you need someone to hide behind if the
    shit hts the fan, or do you mean something else, and if so what?
     
  19. What do you think will happen to QNX if something happens to BBRY/RIM?



    Best regards,
    Spehro Pefhany
     
  20. Yes that seemed peculiar to me too. Typically an open source project has
    every line of every commit signed off and "trackable". As opposed to
    some opaque binary blob that you just have to hope works. (And the
    supplier likely explicitly disclaims all warranty on).

    But I assume Joerg is talking more about something like "certified".
     
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