Announcement

Collapse
No announcement yet.

OT: Oscilloscope Purchase

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • J Tiers
    replied
    Originally posted by dian View Post
    what are " fully isolated separate channels" for?
    For instance, looking at the two gate drives of an SMPS which can be several hundred volts different from each other, AND on the mains side.

    While one can actually "do that" with a regular 'scope, it involves a lot of kludges and does not work that well. The upper gate drive on a half bridge SMPS is varying in base level by several hundred volts at the switching rate, and you are looking for a 15V signal superimposed on that.

    Leave a comment:


  • Mcgyver
    replied
    Hard to beat the venerable Tektronix 465b for a few hundred dollars with probes. That stuff was built properly! and if something does go wrong there is a ton of documentation. I bought a "WON" digital scope some years ago. An " acquaintance" brought it back from the States. What a POS, didn't last a year. I think it used it 3 times. Trail was cold though, buddy (asshat really) never gave me a receipt, vendor was out of the country etc. $500 wasted and the China rip off quality fires stoked again lol

    Leave a comment:


  • skunkworks
    replied
    I like my rigol DS1054Z Haven't touch the surface of all it can do...

    and of course - surprised it did oscope music as well as it did for being digital...





    sam

    Leave a comment:


  • dian
    replied
    what are " fully isolated separate channels" for?

    Leave a comment:


  • J Tiers
    replied
    Yowza... I have not used a 545 since the 1970s. I did have an ex-marine corps AN-105A for a long time, but it's been gone for years. Just recently found another plug-in for it, sitting on a top shelf.

    Give the Fluke a look also. Triggering better than the Teks that I used, and ruggedly built. It's a model 196B, 2 channel, inputs isolated to 600VAC, 100mHz. I got mine for a price similar to what you mentioned.

    Leave a comment:


  • Stan Stocker
    replied
    Greetings!

    I purchased a Hantek DSO5102BM in 2015, to replace my much missed Heathkit 20 MHz analog scope that was utterly worn out and had unobtainable transistors throughout. While a great value for the price, my specific lower end scope has a few limiting features to be aware of. I'm guessing that the other equivalent products have similar limitations too.

    The first is the vertical 8 bit resolution. This limits FFT and such functions to about a 60dB dynamic range, so forget using one for audio or critical analog work where you want to do low level distortion assessments. Not something you could do with a vintage Tek 465 either, but when you see FFT you start thinking that it's a sexy feature (it is) that will let you park your other signal analysers (it probably won't...).

    The second is the actual screen resolution. 800 X 480 is enough to cover the 256 values the scope can display for a signal, but it still feels a bit gritty on the eyes.
    The combination of bit depth and screen resolution limitations means you just can't always zoom in on that critical tiny part of a trace, or be certain if the tiny area you want to look at closely is jitter, sampling artifact, or real signal.

    Lastly is the nature of a DSO versus an analog scope. It can be quirky getting triggering and such sorted neatly, and it's not always obvious that the scope is showing more artifact of the acquisition process than actual signal. As you've used scopes for a long time, odds are somewhere along the line you used sampling plugins on older high end scopes. The same "odd" quirks still apply to sampling scopes, just now we mere mortals can buy them :-)

    There are plenty of positives, I don't want to give the idea that I dislike or regret the scope. For most needs it's a turn it on, clip on the probes, and tell it to get busy auto setting everything for a reasonable display. Pretty good, sort of impressive given the price point.

    If I ever get back into the electronics game to the extent I was in it back in the 70's and 80's a scope with 12 or 14 bit resolution and a higher resolution screen will probably replace the Hantek. For my needs these days, the Hantek is sufficient, doesn't have any really bad habits, and works. It doesn't always give me the confidence in the displayed information, or make me smile the way a vintage Tek 465 ot 7000 series mainframe scope did though. Perhaps if I used it every day for hours at a time I'd be just as comfortable with the Hantek.

    Cheers,
    Stan

    Leave a comment:


  • nickel-city-fab
    replied
    Siglent seems good, but quite honestly I prefer used Tek over almost anything else. You can get them down around $200 nowadays for a 2-ch 100mHz digital storage unit that works fine. Just for old times sake, my main scope right now is a 1953 Tek 545 mainframe scope with the vertical amp plug-in. That also works just fine. Good for audio and AM work.

    Leave a comment:


  • loose nut
    replied
    Rigol seems to be OK but stay away from the import "budget" ones they frequently won't perform as advertised. Imagine someone selling something from China the doesn't work like it should, go figure.

    Leave a comment:


  • eKretz
    replied
    I have been eyeing Siglent scopes for a while now, but probably won't buy one. I already have two Tek TDS754 scopes, so the bench slot is pretty well taken care of. Instead I am holding out for a handheld scope of decent quality. The reason for that is that I want to get something with fully isolated separate channels. So I've been watching for a used Fluke 190-502 or -504 or something similar from Tek or AEMC. Eventually one will turn up at a price that works for me.

    Check some of the youtube reviews from Dave at EEVBlog. He knows his way around a scope very well, and is pretty no-nonsense. I would choose a Siglent over the Rigol personally, but I have heard lots of good things about that Micsig tablet scope too (another one I had been eyeing).
    Last edited by eKretz; 04-15-2021, 10:13 AM.

    Leave a comment:


  • J Tiers
    replied
    Do you demand "brand new"?

    Because used ones do offer a far lower price. I bought a Fluke "Scopemeter" portable a few years ago for well within your budget. It is the larger type, with a big screen, digital, with built-in meter, true RMS, the whole nine yards.

    The trigger options on it are better than the equivalent Tek, and it is isolated for up to 600VAC on each channel, depending on the voltage "category" you need.

    Far more oscilloscope than I would otherwise have obtained at that price. Only downside is the screen is not color, so you need to keep better track of which trace is what.

    Leave a comment:


  • Paul Alciatore
    started a topic OT: Oscilloscope Purchase

    OT: Oscilloscope Purchase

    I know it is a bit off the normal here, but I am at a point where I must purchase a new oscilloscope and I would like any comments from others who have bought one recently. I don't need the basics as I have used scopes for over 50 years. What I want is the practical stuff on the current range of low end, but not too low, scopes. My budget is $250 to $500 and I want one that is self contained, not a module that attaches to a laptop. I already have one of that sort and it is OK for some things but I need something more convenient. For basic specs, a two channel will be enough for my needs and 100 Mhz seems to be a reasonable bandwidth to find. Some have a built-in waveform generator and that would be a welcomed plus.

    I know all about the name brands; Tektronix, HP, and others. They simply are out of my budget so spare me those arguments. What I want and need is some sound advise on the lesser, but still somewhat known brands. I have been looking at Siglent, Rigol, Hantek, and similar models. A couple of models that appear interesting are the Rigol DS1202Z-E and the Hantek DSO2D15. Also the Agilent DSO3152A is a possibility, but it seems to lack many of the features of the other two. Siglent has some nice models, but they always seem to be a bit higher in price.

    Any comments about these or other models that I should consider would be appreciated, especially from those who have one.
Working...
X