Portable scopes / hand held scopes who uses them and why - Page 1
Forum section: electronics / testgear

author: R_G_B_
author_rank: Frequent Contributor
timestamp: August 30, 2015, 03:04:12 pm
content: Not sure if this belongs in this forum.Having been a member of EEVblog for 3 years I have found it very helpful in re-engaging me with my profession. I became severely ill a while back and lost my way. My background was or is electronics engineering and communications engineering.Anyway I Just wanted to know how you guys use your portable oscilloscope scope e.g Field service Automotive etc.What kind of scenarios have you faced with your portable scope. Also what kinds of professions are you guys from.I see a lot of post about people saying you should get a real oscilloscope but does this not depend on the job you are doingand what is your definition of a real oscilloscope vs a toy.Portable scopes can be useful especially for electro mechanical work where the frequencies are much lower and higher voltages.If you wanted to do floating measurements or you wanted to make measurements at both sides of a transformer i guess a portable scope with isolated channels makes sense for this scenario.I am using a fluke 125 it has many features such as power measurements, testing communication protocols, built in data logger and oscilloscope. Pretty good device providing you can use all its features.Interesting to see the measured power of a wall wart 4watts of power dissipated to provide 30 milliamps at 5V to a smart phone.I also used the trend plot function to look at the PWM duty cycle of a fuel metering valve vs fuel pressure.This way you can see the relationship between duty cycle and rail pressure.Using a current clamp you can also analyse the number of commutators on a D.C motor.Anyway here are some uses for a portable labscope:http://www.autolabscopediagnostics.com/Thanks for reading i look forward to reading your repliesR_G_B

author: tautech
author_rank: Super Contributor
timestamp: August 30, 2015, 08:38:04 pm
content: The only need I've had is for reasons of real portability.Siglent make both isolated and non isolated models, both have DMM functionality and logging capability:http://www.siglentamerica.com/pd.aspx?tid=2&T=1

author: MagicSmoker
author_rank: Super Contributor
timestamp: August 30, 2015, 08:52:42 pm
content: I use portable scopes with isolated & floating inputs because I design high power switchmode converters. My all-time favorite is my ancient Tek THS720P but I more recently bought a Chauvin Arnoux (aka Metrix, aka AEMC) OX7104 because the Tek is downright elderly at 20 years old (still working fine, though on its 4th custom ni-cd battery).The OX7104 has a color touch screen, 4 channels and a lot more built-in math functions (FFT, power factor, THD, etc.). It can also store waveforms in data format, not just a screenshot, to a micro-SD card. It performs well - triggering is especially good, for example - but there are enough annoyances with it like the cursors are total crap and the non-standard "smart" probes are flaky (and very expensive!) that I tend to use the THS720P on a daily basis and only pull the OX7104 out when I really need more than 2 channels and/or to store a waveform for later review.

author: McBryce
author_rank: Super Contributor
timestamp: August 30, 2015, 09:02:25 pm
content: I work in automotive electronics. It's rare that we would need a portable scope. Most scope work is done outside the vehicle. If it has to be done in-vehicle, then the car is usually static anyway and a decent normal scope will be used. In moving vehicles most measurements will only require datalogging.McBryce.

author: Joule Thief
author_rank: Regular Contributor
timestamp: August 30, 2015, 09:03:46 pm
content: Even the "nano" scopes can be a great aid in automotive field diagnostics.I have used the nano scopes to differentiate between primary and secondary side ignition issues while standing in 3 feet of snow.The information is not as detailed as a Pico scope can provide but for $60, I rather have one in my kit.

author: HighVoltage
author_rank: Super Contributor
timestamp: August 30, 2015, 09:16:07 pm
content: Well, I also love the Tektronix THS720P and have several of them. I also have clients in the automotive field and sometimes we need to test systems inside the vehicles for all kinds of reasons. One new 5 cylinder, 10 l engine at a large OEM hat huge problems and it was solved with 5 x THS720P, while driving the large vehicle in a mountain range.

author: alsetalokin4017
author_rank: Super Contributor
timestamp: August 31, 2015, 09:24:34 am
content: I've used Fluke 123 and 199 ScopeMeters and also Tek THS720P. They all belonged to my employers, though. I wish I owned a THS720P....The main advantage, other than portability, of the Flukes was the isolated inputs which allow the use of different "ground" references for each channel (up to 600V difference IIRC.) I don't remember if the Tek has isolated inputs.When you need a portable scope... you need one, and especially when you need to be isolated from mains ground and perhaps also isolated channel references.

author: McBryce
author_rank: Super Contributor
timestamp: August 31, 2015, 09:36:16 am
content: I was just down in our lab and the guys tell me they have two Tektronix portable scopes, but they are both still in their original boxes and have extremely rarely been used. Probably because we have the luxury of having a "rolling-road" inside the lab. We also have a "Frame" (19in rack that get's installed where the passanger seat would normaly be located) and this has a non-portable scope installed.McBryce.

author: BravoV
author_rank: Super Contributor
timestamp: August 31, 2015, 09:40:24 am
content: Quote from: alsetalokin4017 on August 31, 2015, 09:24:34 amTek THS7XX series do have complete inputs isolation.

author: R_G_B_
author_rank: Frequent Contributor
timestamp: August 31, 2015, 06:03:15 pm
content: nteresting reading your replys. There seems to be a lot of people using portable oscilloscopes for automotive use. they are a indeed a very valuble tool in this respect.Also the fact the DSO are so small and portable you can carry them in your pocket. I also think a good thing is having the ability to have the oscilloscope to hand when needed. I guess the only problem is the hardware limitation may be down to the size however there will be a point in time where you be able to contain a lot of functionality into a small hand held oscilloscope. The analogue discovery although a PC oscilloscope has a lot of functionality so I guess it can be done its just a matter of time.R_G_B

author: SeanB
author_rank: Super Contributor
timestamp: August 31, 2015, 06:16:22 pm
content: Portable scope is good for many things, I have used my one up a ladder to check a power supply for a camera to see if it was working, or if the camera was actually producing video. Saves half the trouble shooting to see there is video at the camera end and then go along the cable to see where it stops. Plus you can see where you are getting noise in as well, or if the PSU capacitors are past prime.

author: commongrounder
author_rank: Frequent Contributor
timestamp: August 31, 2015, 06:40:11 pm
content: I have a Fluke 199C with a Hantek DSO1122S as a backup. My main application is testing large bridged audio power amplifier installations in the field. The isolated inputs let me test more than one channel at a time without causing problems with the bridged configuration, or do transfer function checks. I can also safely check on mains power with the Fluke (don't trust the Cat. rating on the Hantek). Of course, when one needs to make service calls, anything that can be done to reduce the weight of the gear you need to carry is good!