MSO or logic analyzer - Page 1
Forum section: electronics / beginners

author: clkaczor
author_rank: Contributor
timestamp: February 03, 2015, 04:55:21 pm
content: Do you think it is important or beneficial to buy an MSO scope with a built in logic analyzer or just buy a separate logic analyzer? Is it important to correlate the timing of any analog signals with your digital signals? I am curious to know because I am considering purchasing an MSO or a DSO and then getting a separate logic analyzer. How often would an 8 channel analyzer be sufficient or would 16 channels be more useful? I am a beginner but, when I purchase a scope I would like all the features to be adequate for several years to come without having to purchase another one. I think I may be interested in getting into radio, some microcontrollers and hobby robot kits.Any advice would be much appreciatedThank you

author: Howardlong
author_rank: Super Contributor
timestamp: February 03, 2015, 05:19:51 pm
content: At the stage you're at I'm not sure I'd even bother with an MSO or an LA, get a DS1054Z and apply the hacks. A four channel scope these days is sufficient for almost all microcontroller work. It's pretty rare to use wide parallel busses these days, it's mostly SPI and I2C.I have three MSOs and three LAs here, and I almost never use the digital section of the MSOs or the LAs.

author: clkaczor
author_rank: Contributor
timestamp: February 08, 2015, 04:29:56 am
content: I am just not sure of the advantage of having the logic analyzer integrated in your scope. I also wonder how often does a person need more than 8 channels?

author: rx8pilot
author_rank: Super Contributor
timestamp: February 08, 2015, 04:41:59 am
content: If you are ok with the cost, an MSO is fantastic way to learn. In my learning experiences, having the right tools from the beginning means that your educational efforts are focused on the lessons and not fighting the low-budget test equipment. I have almost always been rewarded by buying more than I need.There is such a good chance that you will outgrow a beginner scope quickly but will suffer through the limitations and not know what you are missing until a couple of years later when you finally break down and replace it. At that time, you will plant your face in your palm wonder why you were fighting the entry level box for so long.Don't spend so much that you cant afford solder, but you will forget how much you paid for the scope when you progress very quickly without immediately being limited by your scope.

author: LabSpokane
author_rank: Super Contributor
timestamp: February 08, 2015, 05:59:59 am
content: Get a 4 channel DSO with a decode package. Used 200 MHz Agilent 2k series DSOs show up occasionally for cheap. And their serial decode is fast. It's a not so good a choice for logging reams and reams of decoded serial info, but you'll know when you need that, and Salae or similar solution is pretty reasonably priced for that purpose. As noted, 8 channels is plenty of logic analyzer for most folks.Tek is running their software bundle specials again, so Keysight isn't far behind.I know every says get the Rigol and hack it. Just suggesting a different path that may be more usable and grow with you for a bit.And try to afford a 200MHz scope. That bandwidth is well within utility for a beginner.

author: rx8pilot
author_rank: Super Contributor
timestamp: February 08, 2015, 06:07:44 am
content: if you can skip Rigol, I would. I have one on my bench that never gets turned on. It is totally upstaged by a 16 year old Tek TDS754C that I got on eBay.

author: clkaczor
author_rank: Contributor
timestamp: February 08, 2015, 06:31:25 am
content: Thank you I appreciate the advice.I do like the Agilents and if they do run specials on software bundles it would make it more reasonable. I do notice that all Rigol MSO's seem to have 16 channels, how often does someone use more than 8 channels or is it mostly I2C and SPI that you could use your analog channels for like others had mentioned. I am not familiar with logic channels but, would like to have them for future use and learning.As far as the Rigols, buying a less expensive version and hacking it I probably could not just take them, I would probably have to pay them for those options. After paying for those upgrades and options an MSO1104Z would cost around $1400 or more.Also when using 4 channels, you only get 250Ms/s, if testing anything close to 100Mhz you really run the possibility of aliasing.Does that sound right.I am really interested to know though how often anyone does use more than 8 logic channels at once.

author: rx8pilot
author_rank: Super Contributor
timestamp: February 08, 2015, 06:52:47 am
content: Quote from: clkaczor on February 08, 2015, 06:31:25 amFor microcontroller work, not often. You can monitor SPI and TWI (i2c) at the same time. I also use them for the various I/O pins to verify timing on signals that have nothing to do with communication. In general, I don't use more than 8 at a time. I will take the development in chunks to make things easier anyway.