[WTB] oscilloscope for beginner - Page 1
Forum section: electronics / general

author: nickn4
author_rank: Contributor
timestamp: June 02, 2015, 08:03:28 pm
content: Hello everyone,Im nick 21 mechatronics- student and hobyist and come from the Netherlands. my full introduction can be found in the "new member introduce yourself here" tread here:https://www.eevblog.com/forum/chat/new-member-please-introduce-yourself/msg685512/#msg685512Long StoryI am looking for an 2nd hand oscilloscope. Dave pointed out in one of his video's to look on eBay, so i have been looking around on ebay for some 2nd hand analog scope 20mhz dual channel. i have no problem finding them but i cannot seem to find a trustworthy add, either it says "powers on, not tested and sold as is" or something similar, or its it says "repair, or parts". and as i am new to oscilloscopes i don't want to need to do tweaking on them. i have a low budget about 50 euro, can pay with ideal and Paypal. i would be happy to hear your advice on what i should look out for and where to look at. to me it would maybe even be better if i could get one from you folks if you have something old laying around that i can still use to get experience from.Short storyI'm looking for a 2nd hand 20mhz oscilloscope for my projects. budget 50 euro (including shipment?)i can use ideal and paypal.i need a little advice where to look and what to look out for (never used ebay before and i don'tYettrust it), if you have something laying around i could use that would be awesome!have a nice daynick janse

author: Wh1sper
author_rank: Regular Contributor
timestamp: June 02, 2015, 08:25:30 pm
content: athttp://www.marktplaats.nl/z/oscilloscoop.html?query=oscilloscoop&sortBy=price&sortOrder=increasingis nothing?look for it, go for it, test it and then buy it

author: PA0PBZ
author_rank: Super Contributor
timestamp: June 02, 2015, 08:42:01 pm
content: Hi Nick,I have a few analog scopes that I wouldn't mind parting from for € 50,-One is a Hitachi V422, the other one a Philips PM3240X.Do some googling and if you are interested let me know, I live close to Amsterdam.(Not sure about probes, I have to do some digging)Paul

author: Isad
author_rank: Frequent Contributor
timestamp: June 02, 2015, 08:42:27 pm
content: Use ebay got mine for about 40$ with the current convert rate.Try and search for a Hameg Hm sereis in the German ebay theyhave some nice prices if you wait for a bit and the auctioncan go really down if nothing pops up with Hameg just try oscilloscope.Hope this helps.I really cant do anything else but if i see somthing reasonable i willlet you know.

author: nickn4
author_rank: Contributor
timestamp: June 02, 2015, 10:08:56 pm
content: thank you all for the fast responses.@Wh1spermarktplaats has a low amount of osciloscopes, could only found 2 within my budget and they dont supply much info. i dont like the brand name either, hung chung or something and its missing probes(sounds chineese cheap quality). and another one that is all red painted from handykit. anyway, they dont attract me at all.. and thats basicly it for marktplaats.nl@PA0PBZHello Paul, i have looked up both models and the Hitachi V422 looks nice and has good reputation. im not sure about that other models though, can you tell me about them in comparison?Even if i might buy one of you, can you give me some more time to do proper research so that i dont act on a impulse?@Isadi have scouted ebay just before creating this thread, i am just not sure at all about those scopes and also not familiar with ebay shipment methods.how do these look to you guys?Tektronix AN/USM-488 2235 100MHz OscilloscopeTektronix 2213 Scope with power cord and one test probeBK PRECISION MODEL 1541B OSCILLOSCOPE 40MHZ POWERS ONLeader LBO-525L Oscilloscope tester Please ReadHitachi V-355 35 MHz oscilloscopeTEKTRONIX 2236 100-MHz OSCILLOSCOPE COUNTER TIMER MULTIMETERTEKTRONIX 2236 100-MHz OSCILLOSCOPE COUNTER TIMER MULTIMETERTEKTRONIX 2236 100-MHz OSCILLOSCOPE COUNTER,TIMER,MULTIMETERThanks alot for your time!nick

author: GreyWoolfe
author_rank: Unknown
timestamp: June 02, 2015, 11:01:10 pm
content: I have a Tek 2235 here and I like the scope. I am afraid that shipping might be very expensive to the Netherlands, though. You won't go wrong with the Hitachi or the Phillips that Paul is offering you. Do yourself a favor and don't overthink it. If you keep hunting for that elusive bargain, you will never find it. Sounds like either of those scopes will get you going. The Phillips has a little more bandwidth, 50 MHz compared to 40 MHz. If Paul can't find probes, they are cheap enough off of eBay to get you started. You have been offered a solid, firm price. The Tektronics scopes will not sell for the current bids, they will go higher.

author: nickn4
author_rank: Contributor
timestamp: June 02, 2015, 11:54:00 pm
content: @graywoolfeyes i kind of figured that much, just needed some confirmation, thanks allot!

author: PA0PBZ
author_rank: Super Contributor
timestamp: June 03, 2015, 07:33:38 am
content: Nick,Take all the time you want, they are not going anywhere soon. I don't have any Tek analog models, the ones I have are either a combination analog/digital or purely digital and a bit more expensive. The Hitachi has always been my own scope (first owner) and the Philips one has a brand new CRT and a very nice NOS (Dutch broadcast corporation) sticker

author: Isad
author_rank: Frequent Contributor
timestamp: June 03, 2015, 03:13:03 pm
content: The Tek are nice and all but shipping from the US is gonacost you soem money.As GreyWoolfe said do your self a favor andget the Philips and you will not go wrong.Probes are easy to finde on ebayand are really cheap.

author: nickn4
author_rank: Contributor
timestamp: June 03, 2015, 04:17:49 pm
content: Thanks for sharing the info Isad, i already have contact with Paul to buy his Hitachi scope. he needs some time to check on the probes, and well if he cant find them of course i will check out ebaybeen studdying all about scopes now. you have some nice videos here on the forums that explain really well, thanks allot to all contributors

author: Isad
author_rank: Frequent Contributor
timestamp: June 03, 2015, 04:55:50 pm
content: Quote from: nickn4 on June 03, 2015, 04:17:49 pmLol yep there are some really nice video about scopes here.Fun fact i got a rigol ds1074z and didnt know how to use after amonth or so had pased i kinda got the hang of it and still to this day idksome stuff on that scope still learning.Hope you get yours as fast as possible.

author: miguelvp
author_rank: Super Contributor
timestamp: June 03, 2015, 06:32:34 pm
content: Forum member KJDS has some interesting offers for UK/EU:https://www.eevblog.com/forum/buysellwanted/fs-uk-eu-scopes-and-psus-etc/Not gems but cheap

author: nickn4
author_rank: Contributor
timestamp: June 04, 2015, 01:10:41 am
content: Yep those are some nice prices, unfortunately i will have to build up a budget before i can start looking for other gear i need such a power supply, however i might try to build something myself firstThanks for the support Isad! you really got me motivated hahahanick

author: Isad
author_rank: Frequent Contributor
timestamp: June 04, 2015, 10:08:08 am
content: Quote from: nickn4 on June 04, 2015, 01:10:41 amLol np bud.If u are lookign for a power supply there are soem niceCV and CC power supply that go up to about 3 amp really cheap and really tinylitl thing works great have won for about 5 month and hasnt let me down and i probably haverekt it by overloading it with 4 amp or more.

author: nickn4
author_rank: Contributor
timestamp: June 09, 2015, 09:43:50 pm
content: I have recieved the Hitachi v422 today. my very first scope ever and also Paul's first scope! Thanks Paul (PA0PBZ)!!!I took pictures from of my very first results i ever got from any oscilloscope check out the attachments if you want to see them.I am having difficulties with the units per division. i suspect i might have turned on some pot what i should not have done?one square on the scope should be the unit you set on the interface right? so if i set 5V/div i should see one square height for a 5V from my arduino?Channel one and two showed different Amplitude's for the same hook up's. i tried correcting it by the red pot's on the volt/div by pulling both until the lines matched up in position.. still don't think the volt/div are correct now thoughpackaging was real top notch btw! 5/5 stars forPaulhmm will look it up myself but if any info can be given personally regardless, that would be great!All tips welcome!nickAttatchments (uploaded to 3rd party, due to big file sizes)Quote

author: Pinkus
author_rank: Frequent Contributor
timestamp: June 09, 2015, 09:55:45 pm
content: Nick,please try to make a photo from the front panel so we can see what settings you are exactly using (e.g. the vertical settings are not visible from the angle the photo was made of).Also it is always better to attach pictures here and not to use an external storage. Why: because then they are always visible, even in 2 years when somebody stumbles upon this.I hate it (and this is not me) if I find forum entries where pictures are gone after a while because somebody deleted them or the service is not available anymore.If you resize the pictures to 1200 or 1600 pixels horizontal size they are usually small enough.

author: nickn4
author_rank: Contributor
timestamp: June 09, 2015, 10:43:10 pm
content: ok, will make a new pair of readings including the settings, will rezise apropriatly (failed last time, files where still too big). and remove pictures from previous post redirecting to this my next comming post. wow that was some sentence there lol.nick

author: Deathwish
author_rank: Unknown
timestamp: June 09, 2015, 10:51:44 pm
content: Looks to me as if you have both traces overlapping each other, are they seperated ?ignore that, it looks like you said you did it deliberately to compare .. sorry

author: rolycat
author_rank: Super Contributor
timestamp: June 09, 2015, 10:54:28 pm
content: Quote from: Pinkus on June 09, 2015, 09:55:45 pmThere are advantages and disadvantages; it is not "always better".Dave has said before that it would be a problem if everyone did as you suggest, and the issue is currently being discussed inthisthread.

author: alsetalokin4017
author_rank: Super Contributor
timestamp: June 10, 2015, 12:10:24 am
content: @Nickn4, congratulations on your scope!It looks to me like your probes need to have their compensations adjusted. If you connect the probes to the scope's Calibrator output (bottom left of control panel next to the CH1 input connector), you should see a nice square wave. The probes will have tiny adjustment caps in the probe itself or the BNC connector; use a small screwdriver to adjust this cap until the square wave from the Calibrator is as "perfect" as possible.If you _know_ you have a 5V signal you can use the Red knobs on the horizontal scale knobs to "fine tune" the display so that it matches the screen graticule divisions as you expect for the V/div setting of the main knobs. You can use a power supply to provide a DC signal of known voltage, or measure a battery with your DMM and then the scope, and set the Red knobs to make the trace show up where it is supposed to wrt the graticule divisions. A fully factory-calibrated scope should read correctly when the Red knobs are turned fully clockwise to the "CAL" detent or mark, but it's not really reasonable to expect an old, used unit to be "perfect" in this regard.

author: nickn4
author_rank: Contributor
timestamp: June 10, 2015, 02:02:05 am
content: Hey thanks everyone for helping me out!I have re- setup everything from previous attempt, using the same schematic.even though i have pictures now, i would like to post my settings and the steps i took to get what you see now.- I have probed Channel ONE parallel over only the LED and the Capacitor and Channel TWO is probed parallel over all components, resistor, LED and capacitor.- I change Volt/Div to .1V/div for BOTH channels, one and two. and change the Time/Div to .5mS/d, so that i can see the oscillation happening. and both volt/d to same amount to compare them.- Now i want to level them out to both have the same 0V reference. i couple both channels to GND and position them on the 0% line.- i change to CHOP mode + Vert mode int trigger to (trigger? is the term) not let the oscillation race around the screen, and still be able to switch any channel to gnd and keep trigger(side note; steps i took are not exactly in this order Btw)- i couple both channels to DC and that is what you can see on the pictures where both lines oscillate.- i took for both channel 1 and channel 2 a picture where to other channel is GND coupledsome questions;1 are my readings on the scope correct now?2 is probing scopes similar to volt meters. However, you cant change polarity when dual channel. and its the same symbols in schematics?3 any tips, warnings or corrections are welcome@Alsetalokin4017;will try and let you know.2 More post for pictures (because of total 2 Mb restriction)thanks for your time!nick

author: nickn4
author_rank: Contributor
timestamp: June 10, 2015, 02:03:48 am
content: 1 More post for pictures (because of total 2 Mb restriction)nick

author: nickn4
author_rank: Contributor
timestamp: June 10, 2015, 02:05:03 am
content: There you have itthis is going really of-topic isn't? perhaps i should port it to the beginner's section?nick

author: nickn4
author_rank: Contributor
timestamp: June 10, 2015, 05:24:41 am
content: @Alsetalokin4017;i did get a square, but the lines where curving up and down a bit, so i leveled it out to be as calibrated as i could get it to be.i compared the results and i definitely see some difference. the curving is disappeared out of my previous signal!thanksnick

author: PA0PBZ
author_rank: Super Contributor
timestamp: June 10, 2015, 07:01:39 am
content: Quote from: nickn4 on June 09, 2015, 09:43:50 pmNick, don't forget that one probe is always x10 and the other one is switchable between x1 and x10. x10 means that the signal is attenuated 10 times, so when you set the v/div at .1v you will get 1v/div on the screen. Leave the switchable probe at x10 and the result on both channels should be the same.I checked the scope before shipping and everything looked correct.

author: nickn4
author_rank: Contributor
timestamp: June 11, 2015, 01:22:25 am
content: Quoteyep thanks alot! have been testing all sorts of stuff and i was confused because of the 10 times magnitude. have progressed a lot in learning how to handle the scope.and yep everything is still good, only thing i notice is the traces slightly bend/curve down at the end of the screen.one more thing: why would it be useful for me to use the x10 probe against the times x1 setting?nick

author: rolycat
author_rank: Super Contributor
timestamp: June 11, 2015, 08:15:49 am
content: Quote from: nickn4 on June 11, 2015, 01:22:25 amTry tweaking the trace rotation preset immediately under the power switch.QuoteTake a look at Dave's vblog on this subject:http://www.eevblog.com/2013/04/13/eevblog-453-mysteries-of-x1-oscilloscope-probes-revealed/

author: nickn4
author_rank: Contributor
timestamp: June 11, 2015, 09:13:15 am
content: Wont be able to try that right a way, will let you know the results.