Jonathan M. Newport <PICLIST@MITVMA.MIT.EDU> wrote:

> I don't really have a lot of experience with them and was wondering
> if all of the analog scopes could capture single events and display
> them.

    Jonathan:

    Only analog STORAGE scopes can capture and display single
    sweeps... With a regular analog scope, the moving finger writes
    and, having writ, moves on.

> and what is the trigger on a scope?  what's a sweep trigger?

    The trigger (or "sweep trigger"; they're the same thing) tells
    the scope when to start a sweep across the face of the screen.

    All scopes allow the trigger to be set for a rising or falling
    edge, a level, and a channel (e.g., you can tell the scope to
    start a sweep when the signal on Channel 1 rises past 3V).

    Some scopes (probably out of your price range) allow more
    complex triggering... Like "Trigger when Channel 1 rises above 3V
    while Channel 2 is below 3V".  A few scopes allow timing
    parameters, too... Like "Trigger when a 5V pulse less than two
    microseconds wide appears on Channel 1 while the signal on
    Channel 2 is below 2V", or "Trigger when a pulse on Channel 1
    DOESN'T happen within 5 milliseconds of a pulse on Channel 2".

> also someone mentioned something about a surplus store or something
> near Columbia MO,  I'm going up there soon and might want to check
> it out.

    There are a lot of companies that sell used test equipment...
    Get a copy of Nuts and Volts, or do a web search for "used test
    equipment".

> does anyone have any company suggestions?  I was thinking about
> ordering from future active which if I buy that tds 210 I get a
> fluke 79 meter for free. The other companies Iv'e called with these
> are the same price (995) but w/o incentive.

    That Fluke meter is pretty nice... Sounds like a good deal.

> I've also looked into some pre-owned scopes....are they safe?

    Depends on who you buy it from.  Personally, I like Pepper
    Systems in Dallas (214 353-0257, ask for Dick Dobson); their
    prices are reasonable and the support is great.

    I paid $2300 for a scope that cost $8000 new, and it arrived with
    a brand-new CRT and fresh calibration.

    When its cooling fan started making noise a couple of months
    after I received it, I called Dick and he not only fixed it, but
    installed a cooling update that Tek recommended AND he paid for
    shipping -- both ways.

> only problem with those is that they all seem to be analog.

    Ask around; most of those guys sell used digital scopes, too.

    -Andy

=== Andrew Warren - fastfwd@ix.netcom.com
=== Fast Forward Engineering - Vista, California
=== http://www.geocities.com/SiliconValley/2499