How much scope for these projects - Page 1
Forum section: electronics / testgear

author: ElectroNub
author_rank: Contributor
timestamp: June 08, 2015, 12:38:42 am
content: I'm starting to learn about scope features and specs and it is a lot to take in. I figure the best way to start is to tell what I want to to work on and ask for direction.I like POWER! I would like to convert a car to electric some day.I like to mess around with power supplies. I would like to build my own 'high end' micro-controller power supply.I like robotics and CNC control. I have a CNC mill and enough parts to convert my lathe to CNC. My mill is more or less a retro-fit kit. My lathe will be modified with my own work and I would like to do my own pcb for the controllers. MORE POWER!!!I would like to mess around with bluetooth and other wireless control. I love all these arduino projects and stuff like that. It almost looks easy to control a CNC machine from android. I also plan to build a laser cutting table in the future. A BIG ONE WITH LOTS OF POWER RAWR!I just like to build things. It's about learning. Knowledge is power. If I can figure out how to build something better than what is already available then I' am going to get richSo, my question is, how big of a scope am I going to need for these types of projects? I'm guessing I will need to plop down a few extra bucks over a 'starter' model. I would like to make this purchase one time only and make it last until I die and pass down to my kids and/or grandchildren. But my budget is not huge either. I have $300 and I may be able to scrape up $400. I don't need a new one. A good used one is well burned inA little help figuring out what I want is appreciated.

author: tautech
author_rank: Super Contributor
timestamp: June 08, 2015, 12:49:10 am
content: Get a DSO, nothing else.With your budget and needs, a 100 MHz unit will be suitable.Your power electronic requirements will probably require a 100:1 probe, maybe a Differential probe and Current probe.These last two will exceed what you have to spend on their own.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: June 08, 2015, 05:24:42 am
content: Quote from: ElectroNub on June 08, 2015, 12:38:42 amThat's a sensible approach.QuoteIf you work with Switch-Mode Power Supplies then you should aim for a 4ch scope that offers power measurements/analysis, which is tremendously helpful to analyze the various interconnected parameters and operating states in a moderate complex SMPS or any other piece of power electronics.Also, don't underestimate the bandwidth necessary when working on power electronics. I'd get a scope with at least 350MHz to 500MHz bandwidth.QuoteAgain, this sounds like a task for a scope with power analysis. Logic analysis would certainly be helpful, so I'd opt for a MSO (scope with built-in logic analyzer), or alternatively some USB logic analyzer that connects to a Windows PC.QuoteYour budget is a problem, as even second hand $400 doesn't buy you that much. There's of course the obvious Rigol DS1054z, which can be hacked to 100MHz (200MHz?) bandwidth, but that's still a very simple scope with limited specs. Some Rigol and Siglent scopes now also offer power analysis, but it's very limited and in my opinion not very useful.As to a second hand scope, you could search for an old LeCroy 9354 or LC300/500 Series scope. These are older but offer advanced power analysis, high bandwidths, advanced FFT and a wealth of other goodies (of which many are still absent even from many newer scopes). The 9354 is a 500MHz 4Ch scope with monochrome CRT, though, and the LC300/500 Series are 500MHz and up scopes with color CRT. Both are from the mid/end of the 90's. though, however with some patience you might get a working one close to your budget.But that's around the cheapest alternative I can think of.At the end of the day, you can do a lot of what you want to do even with a Rigol DS1054z, however you will miss a lot of useful information.QuoteFrankly, I think what really would help is a bigger budget