Advice on low cost handheld OSC ? - Page 1
Forum section: electronics / testgear

author: argile_tile
author_rank: Contributor
timestamp: March 02, 2023, 01:15:26 pm
content: Asking if handheld are "(better) to own as one's only-good-scope" than bench scopes are (given choice between two).I know bench require Differential Probes (diff probe are expensive, difficult to design an op-amp based probe per measurement). Handheld can be used INSTEAD of diff. probe - have a few minus points.EEVBLOG review a few handheld but has not yet reviewed the new Hantek TO1154D. I did already see EEVBLOG Hantek reviews. Mainly I'm wondering if this is because it's absolutely new or because it's basically the Bench model already reviewed.Any comments on advantages of handheld over bench as "one's only good scope" would be appreciated.I think "an acceptable low cost disposable handheld ($200 to $400)" hasn't appeared - too new just released an dall. I don't think I can afford handheld "good enough to diagnose PC power supplies" or what. I can afford a (ie simply smart $600 tablet) if it lasts: but if it dies early and I have to spend $600 over and over - I can't afford that. I'm thinking I'll just wait._____________________* FNIRSIA useful reply in this thread* reminded me of a Tek pdf I read and I re-read it more carefully; I'm becoming more interested in Handheld than Bench.*https://www.eevblog.com/forum/testgear/recent-experience-shopping-for-hobby-scope-in-todays-market-tek-rigol/

author: nctnico
author_rank: Super Contributor
timestamp: March 02, 2023, 01:22:02 pm
content: Quote from: argile_tile on March 02, 2023, 01:15:26 pmWhy do you need a differential probe? If you want to measure mains, using a cheap battery operated oscilloscope won't do you much good because it won't be safe to use. If you want to measure mains you either need to use a CAT rated differential probe OR a scope with CAT rated isolated inputs. Either way, it is expensive.

author: shapirus
author_rank: Super Contributor
timestamp: March 02, 2023, 01:38:23 pm
content: Finally an interesting handheld scope which might justify upgrading my good old JDS6052s. I hate the idea of having to touch the screen with my fingers and much prefer physical controls, though, but I guess it's the necessary sacrifice in this case. If a buggy and/or badly designed UI doesn't ruin it, it may probably be usable.I wonder if this model can simulate phosphor (when the signal trace slowly fades away, as on CRT screens, don't remember the proper word for it). Some of the pictures on the selling pages suggest that it probably can.

author: Fungus
author_rank: Super Contributor
timestamp: March 02, 2023, 01:42:09 pm
content: Quote from: argile_tile on March 02, 2023, 01:15:26 pmNo.Quote from: argile_tile on March 02, 2023, 01:15:26 pmMost bench 'scopes can be used as differential probes using their "math" channels. What you do is connect two probes to the thing under test then subtract one from the other and display the difference on screen.Quote from: argile_tile on March 02, 2023, 01:15:26 pmThe difference between that FNIRSI and a basic Rigol/Siglent is about two orders of magnitude.

author: nctnico
author_rank: Super Contributor
timestamp: March 02, 2023, 02:45:10 pm
content: Still, one of those cheap handhelds is way better than some old 20MHz analog scope. IMHO you can't go wrong when spending up to around US $125 where it comes to cheap equipment.

author: shakalnokturn
author_rank: Super Contributor
timestamp: March 02, 2023, 04:23:14 pm
content: Quote from: argile_tile on March 02, 2023, 01:15:26 pmIMHO no. Although it all depends on your intended use.Even if you're going to be repairing mainly PC PSU's how often do you need to probe the primary side?Is it often enough to sacrifice the usability you'd get from a bench scope's U.I. ?Can't you get away with a 4 channel bench model with the differential probing method mentioned by Fungus, or 2 channel + isolation transformer and/or differential probe when needed?Having both types of scope I'd only recommend the portable fully isolated (i.e.: Not fluke 123) scopes if you're going to be doing mainly field work with live equipment.

author: tautech
author_rank: Super Contributor
timestamp: March 02, 2023, 07:16:12 pm
content: Quote from: argile_tile on March 02, 2023, 01:15:26 pmCertainly not !Common failings of many HH DSO'sPitiful sensitivityLimited feature set and overall capability.

author: Fungus
author_rank: Super Contributor
timestamp: March 02, 2023, 07:27:21 pm
content: Quote from: shakalnokturn on March 02, 2023, 04:23:14 pmAnd we don't know that.(which is completely normal when people ask "what should I buy" questions...)