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I am planning on purchasing my first new oscilloscope since the Heathkit one I built back in the 70's. I'm looking for recommendations and suggestions. My price range is somewhere around $500. I was thinking that a color LCD one would be a good choice.

You didn't mention bandwidth figures, but assuming you are looking for a digital
scope, in
that price range, look at the Rigol DS1052E:



$399, 50Mhz

or the Instek DS-1062A (the A suffix is important):



$415, 60Mhz

I have the Rigol scope and love it, although I ordered it from an Ebay seller
in China, rather than domestically.

Scott




________________________________
From: The Fool <unmitigated_fool@...>
To: NEONIXIE-L@...
Sent: Mon, July 5, 2010 1:38:50 PM
Subject: [NEONIXIE-L] First Oscilloscope

I am planning on purchasing my first new oscilloscope since the Heathkit one I
built back in the 70's. I'm looking for recommendations and suggestions. My
price range is somewhere around $500. I was thinking that a color LCD one would
be a good choice.

On Mon, Jul 5, 2010 at 4:38 PM, The Fool <unmitigated_fool@...> wrote:

I am planning on purchasing my first new oscilloscope since the Heathkit
one I built back in the 70's. I'm looking for recommendations and
suggestions. My price range is somewhere around $500. I was thinking that a
color LCD one would be a good choice.

I'll also nominate the Rigol DS1052E FTW.

Love mine. Around 400 bucks American. You can find it on Amazon.com.

--
carl
--------------------------------------------------------
Henry Carl Ott N2RVQ hcarlott@...

On Mon, 5 Jul 2010 19:09:56 -0400, you wrote:

On Mon, Jul 5, 2010 at 4:38 PM, The Fool <unmitigated_fool@...> wrote:

I am planning on purchasing my first new oscilloscope since the Heathkit
one I built back in the 70's. I'm looking for recommendations and
suggestions. My price range is somewhere around $500. I was thinking that a
color LCD one would be a good choice.

I'll also nominate the Rigol DS1052E FTW.

Love mine. Around 400 bucks American. You can find it on Amazon.com.

And you can hack it to make it 100MHz....

--- In NEONIXIE-L@..., Scott Burris <electroscott@...> wrote:

________________________________
From: The Fool <unmitigated_fool@...>

I am planning on purchasing my first new oscilloscope since the Heathkit one I
built back in the 70's. I'm looking for recommendations and suggestions. My
price range is somewhere around $500. I was thinking that a color LCD one would
be a good choice.
________________________________

You didn't mention bandwidth figures, but assuming you are looking for a digital
scope, in
that price range, look at the Rigol DS1052E:



$399, 50Mhz

or the Instek DS-1062A (the A suffix is important):



$415, 60Mhz

I have the Rigol scope and love it, although I ordered it from an Ebay seller
in China, rather than domestically.

That's a good point. Since almost all of what I'll be measuring is microprocessors in the 5 MHz to 10 MHz range, what bandwidth would be workable. I had been thinking the lowest I could find around 20 MHz. Is that too low to be thinking of? Should I be looking at something higher?

Thanks for the suggestions so far. I've added them to my list to look at.

I am planning on purchasing my first new oscilloscope since the

Heathkit

one I built back in the 70's. I'm looking for recommendations and
suggestions. My price range is somewhere around $500. I was

thinking that a

color LCD one would be a good choice.

If you are doing a lot of logic circuits then I would consider
purchasing a Rigol scope with "D" prefix (I have the DS1022CD
) with a built-in logic
analyzer module. It is not the best analyzer, but quite useful
nevertheless.

Best regards,
Jens

On 7/5/2010 8:32 PM, The Fool wrote:

That's a good point. Since almost all of what I'll be measuring is microprocessors
in the 5 MHz to 10 MHz range, what bandwidth would be workable. I had been thinking
the lowest I could find around 20 MHz. Is that too low to be thinking of? Should I
be looking at something higher?

Thanks for the suggestions so far. I've added them to my list to look at.

Scope bandwidth should be ~10x higher frequency than the signals you're looking at, if these signals are digital. Otherwise you'll see sine waves where you expect square waves.

Also, I doubt that the Chinese scope bandwidth ratings are anywhere as conservative as the ones that Tektronix published in the Good Old Days.

I have a 200 MHz Tektronix scope from the 1970s on my workbench. It's an R7704 with a couple 7A26 plugin amplifiers. These things are very low cost on ebay these days, and they are much higher quality than the stuff made nowadays.

The only problem is that you might have to learn oscilloscope repair.

--
David Forbes, Tucson, AZ

And I would need a MUCH larger bench :)

For digital scopes, figure roughly you need to sample at 10X the rate of the
signal you
want to observe. Yes, I know Nyquist says only 2X, but that's true only if you
want to
look at sine waves. Any other signal will have higher order harmonics which
will get
distorted badly if only sampled at 2X.

And yes, you can cheat somewhat if the waveform is absolutely repetitive,
"equivalent time sampling" in DSO parlance, but I'd argue most interesting
waveforms
aren't strictly repetitive.

So for micros in the 5 to 10Mhz range, you should look at DSO's in the 50 to
100Mhz
range.

Since you already have a Heathkit analog scope, if you really are just
interested in logic
level microprocessor stuff, have you considered a logic analyzer instead?

Some ideas to look at:

Saleae Logic: $149:
USBee SX for $169:

I've got my eye on this unit from Intronix for $389:
I've not tried it,
but I keep hearing good things about it.

Scott






________________________________
From: The Fool <unmitigated_fool@...>
To: NEONIXIE-L@...

That's a good point. Since almost all of what I'll be measuring is
microprocessors in the 5 MHz to 10 MHz range, what bandwidth would be workable.
I had been thinking the lowest I could find around 20 MHz. Is that too low to
be thinking of? Should I be looking at something higher?

Thanks for the suggestions so far. I've added them to my list to look at.

Scott Burris <electroscott@...> wrote:

For digital scopes, figure roughly you need to sample at
10X the rate of the signal you want to observe. Yes, I know
Nyquist says only 2X, ...

Actually, that 2x is the minimum sampling rate, and applies to sampling theory:




Which also applies to DSOs, since that's how the data gets digitized, time wise. To get that 10x component, of your signal, you need 2x of it, or 20x sampling (10 x 2) of the highest signal you wish to observe. For a 1MHz, signal that's 20M samples/second.

If you don't, and the scope has no anti-aliasing filter (a high order low pass filter, set just under half the sampling rate), you'll see signals at frequencies where there really isn't anything:



For example, if you sample a 800Hz sinewave at 1KHz, the data points when plotted will make a 300Hz sinewave, since 800Hz is 300Hz over the Nyquist limit of 500Hz (for 1KHz sampling rate). The signal is said to foldback about the 500Hz.

I see this on the Velleman scope that I own:



Its specifies a 10MHz sampling rate, with a 2MHz bandwidth. It may actually have a good anti-aliasing filter, and the data may be collected properly, but only selective points are displayed dependent on time scale. If that's not done properly, then the aliasing effect will creep back in, which it does.

Even though it has limited bandwidth, I still find it useful, plus I have a couple of old Tek scopes available, when needed. My First scope was, and is (I still have it) a Dumont 304R. It only has a 30KHz bandwidth, and I got a lot of use out of it. Don't use it anymore, but it still works.

For example, if you sample a 800Hz sinewave at 1KHz, the data
points when plotted will make a 300Hz sinewave, since 800Hz is
300Hz over the Nyquist limit of 500Hz (for 1KHz sampling rate).
The signal is said to foldback about the 500Hz.

Oops, that's 200Hz (not 300Hz). I took higher math in college, I swear !

--- In NEONIXIE-L@..., "The Fool" <unmitigated_fool@...> wrote:

And I would need a MUCH larger bench :)

--- In NEONIXIE-L@..., David Forbes <dforbes@> wrote:

I have a 200 MHz Tektronix scope from the 1970s on my workbench. It's an R7704
with a couple 7A26 plugin amplifiers. These things are very low cost on ebay
these days, and they are much higher quality than the stuff made nowadays.

The only problem is that you might have to learn oscilloscope repair.

I had a 7904A - it was a dream 'scope - when I had my first EE job as a student in the '70s (with STL - part of ITT), I had a 7000-series 'scope on my bench - loved them ever since...

When it eventually developed "the tick of death", it was time for it to go - it went to a local FE college along with all my plug-ins...

Now my favourite is a 2465A... just had to replace one of the channel attenuators, but otherwise a truly wonderful 'scope... Also still have a 2403A but hardly ever use that, and a TDS 244 on another bench.

I'll always vote for an analogue 'scope - never know what you're missing otherwise...

Nick

Nick said:

I'll always vote for an analogue 'scope - never know what you're missing

otherwise...

As it happened I was speaking to an engineer a few months ago about vintage
display devices (of which more in a later post) and the subject of digital
scopes came up. He said :

...There are lies, there are damn lies, there are statistics, there are used
car and real estate sales talk and there are even politicians' promises; and
last on that list are what you might see on a digital scope...

(or words to that effect).

As a long time Tektronix analogue scope user, it was music to my ears.

Morris

The Fool wrote:

I am planning on purchasing my first new oscilloscope since the Heathkit one I built back in the 70's. I'm looking for recommendations and suggestions. My price range is somewhere around $500. I was thinking that a color LCD one would be a good choice.

and received lots of advice that looks pretty good. I have a couple of
old analog scopes, a 7704A and a SC501. The 7704 works well and has
reasonable bandwidth, but is really outrageously large and heavy. The
SC503 is fine for its 11 MHz BW. Storage is no longer functional, and
analog storage scopes aren't that great even when they work.

But old as I am, I'm going to stick up for digital scopes. They can do
things the analog ones just can't do. I appreciate the information on
the Rigol products, may have to invest in one. The comments about the
front-end are of course well taken, but that's the same for analog or
digital. My son had one of the Parallax things in high school and it
really isn't useful for much beyond looking at well behaved audio.

And while the USB scopes may not be worthwhile, I've gotten a lot of
mileage out of my Intronix USB logic analyzer. Not as good as the
GoLogic I have at work, but at 1/10 the cost well worth it.


- Rick

The Intronix is on my short list of modern logic analyzers.
Have you had problems with the limited memory? I know they
do compression so it's supposed to go farther than you would
think. Has it worked out for you?

I've got both Tektronix 1240 and Tektronix 3001GPX
logic analyzers (with probes!), but for most uses I'm looking
for something less bulky with UART, I2C, and SPI decoding.
Has to have at least 16 bits, with adjustable voltage thresholds.

Oh, and be reasonably priced. So far, only the Intronix unit seems
to fit all of that. I've looked at the Zero Plus Logic Cube, but their
revenue model seems to be to gouge you for protocol decoding.

Scott



________________________________
From: Rick <rc@...>
To: NEONIXIE-L@...
Sent: Thu, July 8, 2010 6:28:10 PM
Subject: Re: [NEONIXIE-L] First Oscilloscope


And while the USB scopes may not be worthwhile, I've gotten a lot of
mileage out of my Intronix USB logic analyzer. Not as good as the
GoLogic I have at work, but at 1/10 the cost well worth it.

--- In NEONIXIE-L@..., "The Fool" <unmitigated_fool@...> wrote:

I am planning on purchasing my first new oscilloscope since the Heathkit one I built back in the 70's. I'm looking for recommendations and suggestions. My price range is somewhere around $500. I was thinking that a color LCD one would be a good choice.

You've heard a lot of opinions, many from professional engineers with years of experience. However, what they/we like and what you need may be worlds apart.

I suggest you read Tektronix's "XYZ of Oscilloscopes" at .

This is a really good introduction to what scopes can and cannot do, and the differences between analogue & digital versions. It's really a "must read".

Cheers

Nick

Thank you for the link. Looks like I have some reading to do before I make a decision.

--- In NEONIXIE-L@..., "Morris Odell" <vilgotch@...> wrote:

Nick said:

I'll always vote for an analogue 'scope - never know what you're missing

otherwise...

As it happened I was speaking to an engineer a few months ago about vintage
display devices (of which more in a later post) and the subject of digital
scopes came up. He said :

...There are lies, there are damn lies, there are statistics, there are used
car and real estate sales talk and there are even politicians' promises; and
last on that list are what you might see on a digital scope...

(or words to that effect).

As a long time Tektronix analogue scope user, it was music to my ears.

Morris

I have both an analog scope (Tek 465) and a DSO (Bitscope) and they both have advantages and disadvantages. I like the "real" aspect of the analog scope. The CRT responds in real time to whatever is on the input. On the other hand, the DSO is able to capture a portion of a complex waveform where it can then be studied in detail. I tend to use the analog scope when I'm first poking around, and the digital scope when I want a close look at something like a serial data stream or transient event.

--- In NEONIXIE-L@..., "James" <jamesrsweet@...> wrote:

...There are lies, there are damn lies, there are statistics, there are used
car and real estate sales talk and there are even politicians' promises; and
last on that list are what you might see on a digital scope...

I have both an analog scope (Tek 465) and a DSO (Bitscope) and they both have advantages and disadvantages. I like the "real" aspect of the analog scope. The CRT responds in real time to whatever is on the input. On the other hand, the DSO is able to capture a portion of a complex waveform where it can then be studied in detail. I tend to use the analog scope when I'm first poking around, and the digital scope when I want a close look at something like a serial data stream or transient event.

The answer to that?
Why! A Tek 464 / 466 of course! I know Storage CRTs have pitfalls of their own, the least of them being that the tubes are made of an unobtanium isotope, but that what even quantities were made for! (I have 2, and specifically bought that model as many in the group have confessed, out of the "first love" experience).
I have also worked with DSOs in the past, old ones but DSOs anyway and not toys. They do allow detailed analysis, plus have some other functions that analog scopes don't even dream to have.
But similar things go together so for the digital realm, DSOs seem to be good, however if I suspect a d*rned fast glitch in a digital bus, I won't change my analog scope for anything in the world. After all, at today's switching speeds, square waves simply don't exist.