Beginner scope for repairs? - Page 1
Forum section: electronics / beginners

author: _ar_
author_rank: Contributor
timestamp: July 15, 2018, 07:40:00 am
content: Hi,I'm looking into buying a scope to start to learn how to use one. I am a hobbyist doing retro computer troubleshooting/repairs in my spare time (old pc, commodore stuff). I do not have space for keeping a scope on a desk all the time, so size matters. I do have an ipad/iphone which would be nice to be used as a screen. Using my notebook as a screen would be fine as well (I have a Mac, but I can run WinXP in Virtualbox as well).What would be my best option? Are the Owon/Hantek USB scopes still recommended for beginners? What about those e-design mini handheld scopes? Thanks for your help!

author: BravoV
author_rank: Super Contributor
timestamp: July 15, 2018, 07:48:00 am
content: Budget ? Includes the shipping to your country if you have to import it.

author: _ar_
author_rank: Contributor
timestamp: July 15, 2018, 07:54:44 am
content: I'd rather think long the line of 'what fits my needs best' rather then budget atm. Cheaper is ok if it does not come with annoying limitations in usability. Shipping inside EU or from China (usually free) is of no concern.

author: BravoV
author_rank: Super Contributor
timestamp: July 15, 2018, 08:50:57 am
content: Quote from: _ar_ on July 15, 2018, 07:54:44 amOk, expecting this thread will grow up to multiple pages of recommendations ranging from $50 scope up to 3 or 4 digits priced scope. Good luck.

author: tggzzz
author_rank: Super Contributor
timestamp: July 15, 2018, 09:18:21 am
content: Make sure you understand theprobes, their characteristics and limitations - particularly w.r.t. voltage, frequency, and voltage vs frequency.There are many threads discussing this on this forum.

author: tautech
author_rank: Super Contributor
timestamp: July 15, 2018, 09:19:55 am
content: Quote from: _ar_ on July 15, 2018, 07:54:44 amYour 'needs' seem very basic so I ask why you can't get by with a good DMM and a logic probe ?Tell us why do you think you must have a scope ?

author: _ar_
author_rank: Contributor
timestamp: July 15, 2018, 11:55:30 am
content: Yes, I do think that I'd be ok with a logic probe. However, there are some repair guides I found that even show what waveform I need to see on an oscilloscope when an IC is healthy. Also, do you think that loosing the 'time' information by using a logic probe is not important?

author: Kleinstein
author_rank: Super Contributor
timestamp: July 15, 2018, 12:08:56 pm
content: A scope may really help in some cases for such repairs. If there would not be the space limitation I would guess the low end Rigol DSO (e.g. 1054) would be good enough.Those small handheld ones have a rather limited screen size. So they do have limitations and can not really replace a real scope.The cheaper USB scope may be connected to the computer ground - this could add some noise if the DUT is grounded (e.g. old PC). I am not sure how well those USB scope work in the Virtual Box - definitely a point to check before buying one.Another point to look for the USB/handheld ones it the voltage range. Some are limited at the low or high end.

author: Nitrousoxide
author_rank: Regular Contributor
timestamp: July 15, 2018, 12:12:06 pm
content: With how generic the requirements are. I'd say stay away from the cheap, portable scopes.Go for a Rigol DS1000z, or an equivalent scope (siglent etc) with 4 channels. The extra channels do come in handy quite regularly.Im going to make an assumption that you already have the other essentials i.e. Multi-meter.

author: rstofer
author_rank: Super Contributor
timestamp: July 15, 2018, 04:05:58 pm
content: This topic comes up a couple of times per week. The recommendations are always the same because there simply isn't any new information.If you want a real scope, the Rigol DS1054Z (unlocked, search for Riglol) is one option and the newer Siglent SDS1202X-E (200 MHz 2 Channel) or SDS1104X-E (100 MHz 4 channel) scopes are another. The 1104 can be unlocked to 200 MHz so it is a really attractive choice.A logic analyzer can be a bigger help but it assumes that you have all the signals. The scope helps find out whether the lines wiggle at all. Both are necessary at some point.The Digilent Analog Discovery with the BNC adapter board is another possibility. It works well and it is PC based. It doesn't have near the bandwidth of the Rigol or Siglent offerings. Vintage CPUs don't work at high frequency anyway and I used a 10 MHz scope for years and years. It also has a logic analyzer, a dual channel signal generator, dual channel scope, dual power supplies, pattern generator and so on. I like mine!A full size scope, like the Tektronix 485, can sit upright on the floor and is easily stored under the bench. That's the way I use mine. All of the 4xx series are luggables, intended for transporting to job sites and used in an upright orientation. It takes a pretty deep bench if they are to be used laying down.You can't realistically evaluate scopes without driving a stake in the ground on price. I guarantee you, the Keysight $300,000 scope is going to have better specs than the $350 Rigol. The Keysight is probably out of reach for most hobbyists but it does give you an idea of the range of prices. You really do need to get a handle on how much you want to spend. It doesn't have to be a hard limit but if the number is something like $100 then you are looking at used analog scopes of dubious functionality. For $200, you can get a pretty decent used analog scope. For $350 you can get a new Rigol or perhaps Siglent. For $500, you can get something else (maybe) and when you get to the $1000 or $2000 range you should be able to get a very nice scope (but I don't have a recommendation).For workable entry level scopes, the Rigol or Siglent will do the job.

author: _ar_
author_rank: Contributor
timestamp: July 15, 2018, 04:09:50 pm
content: Thank you all for your input!

author: PA4TIM
author_rank: Super Contributor
timestamp: July 15, 2018, 04:53:26 pm
content: I do repair work and this can involve the same old digi-stuff (but then most times in industrial/automotive stuff and sometimes older measurement/calibration gear)What about a scopemeter ? I have a 60 MHz from Siglent SHS-1062, (isolated but there is also a much cheaper normal version). Although I have 2 scopes on my bench, I use the Siglent more often as I expected when I bought it. (I made a (youtube) review:http://www.pa4tim.nl/?p=5896)I also have a HP logic probe and HP 547 current tracer, the latter is very handy. I only miss the current inserter (So I use a DIY one) I think a logic probe is handy but for me not a scope replacement. I want to see what is going (wr)on(g). But I think for your use it can often replace a scope (In my case it is often a mix of analog and digital circuits)I use 3 logic analysers. The one of my DSO for real time HW trouble shooting, a Tek 1241 for old stuff with a lot of lines to monitor (check if all control lines are active and with a correct timing, and a Zero-plus for decoding (if I really have to good deep). But I could live without them most of the time (but the times I need them I am happy I have them)I also have a meter-scope,a DMM with a simple scope instead of a scoop with a simple DMM like the Siglent. That is my number one meter and most used instrument. A Keithley 7510 (but before you think, that is handy, be sure that you first sit down before you google it because this is not a hobby grade DMM,

author: Gyro
author_rank: Super Contributor
timestamp: July 15, 2018, 04:59:05 pm
content: Quote from: _ar_ on July 15, 2018, 07:40:00 amWithout entering into the undefined budget issue, to answer this specific question from your OP....If thinking about Hantek / Owon USB scopes then the sensible option is the Owon VDS1022I- the USB isolated version. Then you won't have any issues with noise or PC damage due to ground loops (accidental or not). The S/W works from Win XP to Win10. Not sure how well it would work in virtualbox. If you look at the later pages of the teardown thread then you will see that some folks have been doing investigation in that area.https://www.eevblog.com/forum/testgear/owon-vds1022i-quick-teardown-(versus-the-hantek-6022be)/Now to continue the discussion on what scope actually suits your needs...

author: Jwillis
author_rank: Super Contributor
timestamp: July 16, 2018, 04:41:44 am
content: Commodores typically ran from 1Mhz to 4Mhz .Even the VIC ran at systems clock ,around 1 Mhz for NTSC and if I remember 980Khz for PAL.So a 20Mhz oscilloscope is plenty .You don't need the most powerful scope on the market.Even a used analog 20Mhz would do just fine .It all depends on your budget.

author: tggzzz
author_rank: Super Contributor
timestamp: November 16, 2018, 09:31:51 am
content: Quote from: KissAnalog.com on November 16, 2018, 09:07:03 amSorry, I'm not going towastespend 25 minutes of my remaining life to find out what you could state with 2 mins typing and all of us could read in 30 seconds.

author: james_s
author_rank: Super Contributor
timestamp: November 16, 2018, 05:20:25 pm
content: You'll definitely want a DSO for this sort of work, people got by for years with analog scopes but this is the sort of thing where DSOs really shine. If it's within your budget, I'd say grab the Rigol or one of the similar popular scopes in that price bracket. They're compact, (relatively) inexpensive and will do what you need.