buying first scope, looking for advice

[Boltz]

If you guys were buying an oscilloscope now, what would you buy and why? I'm looking to get something for under $200, can I get a unit which will cover the bulk of the work involved in building and troubleshooting machine tool controls for that price?

-Jim Hart

[Al_The_Man]

I have a Tektronix D.B. 'scope and the Syscomp storage scope, for the most part I use the Syscomp, It save me lugging the (heavy) Tek around to job sites.
Plus it is nice to store screens for future ref etc.
It has a high enough frequency coverage for most CNC related situations.
Also it has the ability to capture on event trigger, so if you are looking for a particular noise pulse to occur you can set it and leave it.
Since I bought mine, I see they have a comprehensive model, several functions in one, $189.00.
http://www.syscompdesign.com/CGR101.html
Al.

[ImanCarrot]

Some of them state they are "Dual Channel", but they only have the capability to display two separate channels. I've found in ceratin circumstances I've needed to combine two different channels to get a lisajou figure (sp?) when I'm trying to tweak the output of my motors' board drivers.

Worth considering.

Also a storage scope is handy (but not essential).

I doubt, however, you'll get a new one for 200 USD, but I'll be pleased to be corrected. Flea Bay might get you there, I've bought a few off them and they worked fine. Got a nice little portable digital scope second hand- neat if you're doing off site maintenance.

[Boltz]

Wow, I admire your skill, Iman, if you can debounce a relay or switch without storage capabilities.

I've looked at the Parallax (about$135), and it doesn't look fast enough.

The 2 leading candidates now are the Syscomp Al mentioned, and the Hantek 2090, both in the $190 range. The Syscomp looks like a geeky adventure, with open-source software that has to be manually installed. On the plus side you can write your own custom display software in "tickle-tock" (Tcl/Tk).

The Hantek has been harder to find out about, although there are hundreds for sale on the Large Auction Site.

-Jim Hart

[Al_The_Man]

Originally Posted by ImanCarrot Some of them state they are "Dual Channel", but they only have the capability to display two separate channels. I've found in ceratin circumstances I've needed to combine two different channels to get a lisajou figure (sp?) when I'm trying to tweak the output of my motors' board drivers.

The XY mode should do it?
http://www.syscompdesign.com/Screens...GR-Screen4.jpg
Al.

[ImanCarrot]

Wow, I admire your skill, Iman, if you can debounce a relay or switch without storage capabilities

Take your point Boltz, but I don't use mine for that, only for calibrating the output of my PMAC board as I move the laser positioning system.

I get two sine waves which are out of phase- if they're combined I get a circle (think it's called a lisajou figure).

The Fluke scope I had was advertised as Dual Channel, it'd display the two channels, one above the other, but couldn't combine them.

I bought a Tektronics whichcould combine them.

Anyway, go with Al's advice... my field is pretty narrow, he knows more.

[Boltz]

I knew I was bound to get a Tek loyalist with an inquiry like this... they are beautiful instruments. Storage and datalogging capabilities are pretty compelling, though.

Hey Al, I've seen some criticism of the Syscomp installer. Did you have any trouble intalling the software?

-Jim Hart

[Al_The_Man]

The only problem I had was initially I installed it on my laptop that had Win98 and it was written for XP at that time, so they sent me a USB driver for it.
Other than that it has been working well on both 98 and XP.
The Tech support was very good.
Al.

[vger]

Jim

Here is my two cents...

I've been using oscilloscopes since the mid 60's and when I look for a new one, one of the first features I look for is storage capability. The second specification is Band Width. If you have a "glitch" you are trying to track down, you want something that is fast. I've used EICO, Phillips, HP, Tektronics, Hickok, Fluke, and others. Even used a sampling digitizer to observe microwave waveshape for radar (X Band 10.4 GHz).

My current scope is a Tektronix 466 100Mhz storage scope. Yeah it's what I call a "luggable" but it performs well and will capture events that would scream right on by a digitizer with a 20Mhz sample rate. If I need documentation of a trace, I take a pic of the screen. Not real elegant I know but it works. I've got a couple of amprobe clamp-on's that allow me to monitor current waveforms. Great for troubleshooting motors, and VFDs.

Just a quick search on ebay netted this one....

http://cgi.ebay.com/Tektronix-468-10...item4151878c63

Hope you enjoy whatever you decide to get.

Steve

[ImanCarrot]

I take a pic of the screen

I thought I wasthe only person that did that! I used aPolaroid scope camera- it looked like a camera with a big square funnul on the end.

[Boltz]

Is it possible to take a useful digital photo of the screen?

As somebody who's never been "hands-on" with a Tek, or any other scope for that matter, the idea of having the scope function comfortably embedded in my PC is pretty appealing.

-Jim Hart

[michaelaneccent]

Have a look at www.uni-trend.com.cn this the scope i use, hand held and also U.S.B. link to the computer if you wish. 8 meg band width. Model UT81B.

I hope this is of some use,Michael an eccentric Englishman city of Nanning China.
Was about $150. in Nanning