[time-nuts] A little quick advice, please

Sun Oct 31 19:19:45 UTC 2010

Like hammers, every tool has it's place and if you only have one
hammer, everything looks like a 10penny nail.

As a guy with an unfortunate affliction to test equipment, (as do many
of you, I'm sure) I've got a 7000 series analog scope which I love, a
tek 2236 portable, a DS602 digital, and a parallel port PC based
digital. Each has it's place.

Nothing beats the Tek 7000 series for flexibility and bang for your
buck. From simple, low speed time bases and vertical amplifiers,
through the various digital plugins such as counters and logic
analyzers, the spectrum analyzer plugins, through the very high speed
time bases and plug ins. The joy is that it allows you to start with
something that works for your early needs and a wide range of upgrade
paths. Plugins are plentiful and relatively inexpensive. Between a
large box of plug ins and the mainframe itself, I think I might have
$500 invested. The spectrum analyzer was another $400.

The DSA602 was an impulse purchase that I think I probably could have
lived without. The 1Ghz bandwidth plugins are not easily found, but
the FFT function is very handy. My biggest complaint is that it takes
too long to boot up! Again, an inexpensive option for a scope, good
into the ghz range for a few hundred dollars.

The older PC based scopes are just too slow for most of what I do
anymore, though they are handy logic analyzers if you only need a few
channels. For many channels, an Tek 1240 or 1241 is tough to beat.
Less than $100, $50 if you search for up to 32 channels just makes
doing that job simple.

Your worries about warrantee are quite valid. But if I can get a used
scope or bit of test equipment for less than $0.50 on the dollar of a
new one, it's a pretty good bargain for home use. If it is for work,
whole different story. That's where the 2236 came in. I was making a
living on the road doing field service. It couldn't break or I'd be in
deep sneakers. So it arrived new in a box. Of course that was many
many moons ago.

Bob
KI2L

On Sun, Oct 31, 2010 at 2:42 PM, Robert Darlington
<rdarlington at gmail.com> wrote:
> Hi Alan,
>
> My $200 Tek 7854 mainframe with the 7S11/7T11 combo take my old scope up
> high enough to look at 13-14GHz repetitive signals.  I don't think it can
> take a screen shot or do much if any analysis with these plugins though but
> they're still handy for a lot of things.  I love the digital storage analog
> scopes of the 80s but the modern digital scopes have their place too.
>
> -Bob
>
> On Sun, Oct 31, 2010 at 12:13 PM, Alan Melia <alan.melia at btinternet.com>wrote:
>
>> Sampling scopes will display repetative signals above the sampling
>> frequency
>> if the repetition rate of the signals and sampling rate are not
>> related....there were GHz bandwidth scopes in the 60s using this method.
>> Not
>> a lot of good on single shot though. PC scopes are quite good for
>> repetative
>> slow signal and single shot within their sampling rate. i have a Pico Tech
>> 50Ms/s which works well with a simple old laptop.....it requires a parallel
>> port so was quite cheap on that auction site we love to hate.
>>
>> It is a case with ALL measuring equipment you been to know HOW it works to
>> interpret what it telling you.
>>
>> Alan G3NYK
>>
>> ----- Original Message -----
>> From: "William H. Fite" <omniryx at gmail.com>
>> To: "Discussion of precise time and frequency measurement"
>> <time-nuts at febo.com>
>> Sent: Sunday, October 31, 2010 5:06 PM
>> Subject: Re: [time-nuts] A little quick advice, please
>>
>>
>> > Robert said;
>> > Bitscope headlines "100MHz analog bandwidth" but you have to big a bit
>> > deeper to find "up to 40Ms/s". Seems like they are wasting most of the
>> > bandwidth if the have an anti-alising filter. This is really only usable
>> to
>> > 20MHz single shot.
>> >
>> > Yes, I noticed that, too.  Almost sounds like deceptive advertising.
>> >
>> >
>> >
>> >
>> > On Sun, Oct 31, 2010 at 11:28 AM, Robert Atkinson
>> <robert8rpi at yahoo.co.uk>wrote:
>> >
>> > > Hi Bill,
>> > > It depends what you need/want. There are issues with the PC based
>> 'scopes.
>> > > Most obvious to the user is response time. It can be fustrating to have
>> the
>> > > screen change a second after the event happened! Other issues are
>> sample
>> > > rate and input voltage range. The Bitscope headlines "100MHz analog
>> > > bandwidth" but you have to big a bit deeper to find "up to 40Ms/s".
>> Seems
>> > > like they are wasting most of the bandwidth if the have an anti-alising
>> > > filter. This is really only usable to 20MHz single shot.
>> > >  I could not find the input sensitivity and ranges. I looked at the
>> > > BitScope a while ago and decided it was overpriced at $600. I was lucky
>> to
>> > > find an HP 54645D for the same money. Unless you need the PC
>> connnectivty
>> > > and simple logic analyser (the 54645D gives both ;-), I'd look at a
>> > > conventional 'scope. As you are considering a PC 'scope, have a look at
>> the
>> > > Pico Technolgy range,
>> > > http://www.picotech.com/oscilloscope-specifications.html Their
>> bandwith
>> /
>> > > sample rates make more sense. I've used their products and they work
>> very
>> > > well.
>> > >
>> > > Robert G8RPI.
>> > >
>> > > --- On Sun, 31/10/10, William H. Fite <omniryx at gmail.com> wrote:
>> > >
>> > > From: William H. Fite <omniryx at gmail.com>
>> > > Subject: [time-nuts] A little quick advice, please
>> > > To: "PC Oscilloscope" <time-nuts at febo.com>
>> > > Date: Sunday, 31 October, 2010, 13:35
>> > >
>> > > 'morning, folks,
>> > >
>> > > I was just on a verge of purchasing a Tek TDS1012 scope when a friend
>> > > suggested that I could save a chunk of change by buying a BitScope.
>> > > Although
>> > > I've been aware of PC scopes, I never really looked into them.  The
>> specs
>> > > look pretty good (the fact that I was looking at an entry-level Tek
>> will
>> > > give you some idea of my needs).
>> > >
>> > > Anyone have any experience with BitScope or other of the low-end PC
>> scopes?
>> > >
>> > > Thanks,
>> > >
>> > > Bill
>> > >
>> > > _______________________________________________
>> > > > time-nuts mailing list -- time-nuts at febo.com
>> > > > To unsubscribe, go to
>> > > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>> > > > and follow the instructions there.
>> > > >
>> > > _______________________________________________
>> > > time-nuts mailing list -- time-nuts at febo.com
>> > > To unsubscribe, go to
>> > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>> > > and follow the instructions there.
>> > >
>> > >
>> > >
>> > >
>> > > _______________________________________________
>> > > time-nuts mailing list -- time-nuts at febo.com
>> > > To unsubscribe, go to
>> > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>> > > and follow the instructions there.
>> > >
>> > _______________________________________________
>> > time-nuts mailing list -- time-nuts at febo.com
>> > To unsubscribe, go to
>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>> > and follow the instructions there.
>>
>>
>> _______________________________________________
>> time-nuts mailing list -- time-nuts at febo.com
>> To unsubscribe, go to
>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>> and follow the instructions there.
>>
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>