A good digital oscilloscope?
in [Design]
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From: Jamie on 7 Dec 2009 20:24 Tim Williams wrote: > I never was too impressed with digital scopes. None of them have nearly > enough buttons, so you spend all your time wading through menus. The Rigol > I've used (don't remember the number) has awful menus, they are not always > quite what they say they are, and they take forever to go away. > > Some digital scopes have better refresh than others. The HP (Agilent??) > 54622D's in all the labs at school here work fairly well, though at least > two button presses are required to reach any given menu option. Refresh is > okay, though still chunky on slower sweeps (>1ms/div). > > My impression of the cheapass Tek TDS's (the thin rectangular ones) is > similar to the Rigol. > > I'm most familiar with my Tek 475, but it would be nice to have storage, > single sweep* and averaging. One of those intermediate scopes, the ones > with analog AND digital, they're perfect for everything. > > *Just because it's an analog scope doesn't mean you don't get storage or > single sweep type readings, it just means it takes more setup. This > photograph was taken with a 10 second exposure, capturing three photoflash > discharges: > http://webpages.charter.net/dawill/Images/Photoflash_Discharge2_sm.jpg > > Tim > My Tek 485 serves me well. I do have a small assortment of digital scopes for portable use to gather basic data and road trip testing how ever, I find that my 485 still gives me nice results at the bench as long as I don't need live digital storage. It's the only scope I have that I can take full advantage of my active Fet probes when I need them.
From: Joerg on 7 Dec 2009 21:12 Jan Panteltje wrote: > On a sunny day (Mon, 07 Dec 2009 15:00:29 -0800) it happened Joerg > <invalid(a)invalid.invalid> wrote in <7o5fogF3lr6q7U1(a)mid.individual.net>: > >> Jan Panteltje wrote: >>> On a sunny day (Mon, 07 Dec 2009 14:44:29 -0800) it happened Joerg >>> <invalid(a)invalid.invalid> wrote in <7o5eqhF3mttuiU1(a)mid.individual.net>: >>> >> [...] >> >>>>> Its a nice scope, good TV trigger, dual channel. >>>>> Graticule is broken... >>>> How did that happen? Grandkids playing too rough? >>> Weller dropped on it, I had the scope vertical on the ground, >>> the Weller dropped (transformer part) on the screen from the table. >>> Now it is 2 halves. >>> I have some acryl plastic, maybe one day will I draw a grid on it... >> >> You may not have to draw. Could you print onto overhead projector film? >> The stuff that executives used instead of PowerPoint back in the >> Neanderthal days. If you put that between the CRT surface and a plastic >> piece it would look nicer than something drawn by hand. > > Yes that could work. > With drawing I ment use sharp knife to make grooves in the acryl, > and then rub some ink into it perhaps. > Yes I have those clear sheets for making PCB layouts on the inkjet printer. > That would indeed be nicer, but it would have to stick onto the acryl somehow. I used to have a set from Tektronix for an old scope. A clear plastic piece for the front and then a stash of thin films with all sorts of graticules on there. All this was exactly the size of the CRT frame so the positions were fixed by just laying them in there. First the film piece, then the plastic protector. IIRC it just slid in from the top. Guess they didn't have MS-Excel in those days and whatever shot you took with the old Polaroid was pretty much it. You couldn't even work with white-out on those, they had to go into the document as is. > Just be studying that diagram, there is an intensity preset pot, good, > maybe that is all I need to tweak, (it is too bright, cannot dim it). > Could accidently have turned that during calibration... Or the wiper could have developed contacting issues. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Joerg on 7 Dec 2009 21:16 John Larkin wrote: > On Mon, 07 Dec 2009 11:56:59 -0800, qrk <SpamTrap(a)spam.net> wrote: > >> On Sun, 06 Dec 2009 20:29:24 -0800, John Larkin >> <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >> >>> On Sun, 6 Dec 2009 22:18:04 -0600, "Tim Williams" >>> <tmoranwms(a)charter.net> wrote: >>> >>>> I never was too impressed with digital scopes. None of them have nearly >>>> enough buttons, so you spend all your time wading through menus. The Rigol >>>> I've used (don't remember the number) has awful menus, they are not always >>>> quite what they say they are, and they take forever to go away. >>>> >>>> Some digital scopes have better refresh than others. The HP (Agilent??) >>>> 54622D's in all the labs at school here work fairly well, though at least >>>> two button presses are required to reach any given menu option. Refresh is >>>> okay, though still chunky on slower sweeps (>1ms/div). >>>> >>>> My impression of the cheapass Tek TDS's (the thin rectangular ones) is >>>> similar to the Rigol. >>>> >>>> I'm most familiar with my Tek 475, but it would be nice to have storage, >>>> single sweep* and averaging. One of those intermediate scopes, the ones >>>> with analog AND digital, they're perfect for everything. >>>> >>>> *Just because it's an analog scope doesn't mean you don't get storage or >>>> single sweep type readings, it just means it takes more setup. This >>>> photograph was taken with a 10 second exposure, capturing three photoflash >>>> discharges: >>>> http://webpages.charter.net/dawill/Images/Photoflash_Discharge2_sm.jpg >>>> >>>> Tim >>> I like my TDS2012. I rarely use an analog scope any more. >>> >>> John >> I find that I use an analog scope (Tek 465) for analog stuff. Can't >> get a feeling for noise issues with a digital scope. For pulse >> amplifier stuff and when you need arithmetic, digital is the way to >> go. > > I find analog scopes confusing. All the traces are the same color. > But the higher end ones with long-delay phosphor glow in the dark. Once I slept here in the lab on a make-shift bed. There was this eerie blue glow from over yonder. Digital ones are easier with the colors, of course. If they just hadn't picked blood red for the FFT and bonbon purple for Ch3 on mine. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: a7yvm109gf5d1 on 7 Dec 2009 22:52 On Dec 7, 12:35 pm, Robert Roland <f...(a)ddress.no> wrote: > > I have an ancient Tektronics analog scope, which has storage and They must have gotten sued by Tektronix. Never heard of 'em.
From: John Larkin on 7 Dec 2009 23:21
On Mon, 07 Dec 2009 18:16:49 -0800, Joerg <invalid(a)invalid.invalid> wrote: >John Larkin wrote: >> On Mon, 07 Dec 2009 11:56:59 -0800, qrk <SpamTrap(a)spam.net> wrote: >> >>> On Sun, 06 Dec 2009 20:29:24 -0800, John Larkin >>> <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>> >>>> On Sun, 6 Dec 2009 22:18:04 -0600, "Tim Williams" >>>> <tmoranwms(a)charter.net> wrote: >>>> >>>>> I never was too impressed with digital scopes. None of them have nearly >>>>> enough buttons, so you spend all your time wading through menus. The Rigol >>>>> I've used (don't remember the number) has awful menus, they are not always >>>>> quite what they say they are, and they take forever to go away. >>>>> >>>>> Some digital scopes have better refresh than others. The HP (Agilent??) >>>>> 54622D's in all the labs at school here work fairly well, though at least >>>>> two button presses are required to reach any given menu option. Refresh is >>>>> okay, though still chunky on slower sweeps (>1ms/div). >>>>> >>>>> My impression of the cheapass Tek TDS's (the thin rectangular ones) is >>>>> similar to the Rigol. >>>>> >>>>> I'm most familiar with my Tek 475, but it would be nice to have storage, >>>>> single sweep* and averaging. One of those intermediate scopes, the ones >>>>> with analog AND digital, they're perfect for everything. >>>>> >>>>> *Just because it's an analog scope doesn't mean you don't get storage or >>>>> single sweep type readings, it just means it takes more setup. This >>>>> photograph was taken with a 10 second exposure, capturing three photoflash >>>>> discharges: >>>>> http://webpages.charter.net/dawill/Images/Photoflash_Discharge2_sm.jpg >>>>> >>>>> Tim >>>> I like my TDS2012. I rarely use an analog scope any more. >>>> >>>> John >>> I find that I use an analog scope (Tek 465) for analog stuff. Can't >>> get a feeling for noise issues with a digital scope. For pulse >>> amplifier stuff and when you need arithmetic, digital is the way to >>> go. >> >> I find analog scopes confusing. All the traces are the same color. >> > >But the higher end ones with long-delay phosphor glow in the dark. Once >I slept here in the lab on a make-shift bed. There was this eerie blue >glow from over yonder. > >Digital ones are easier with the colors, of course. If they just hadn't >picked blood red for the FFT and bonbon purple for Ch3 on mine. This is a 4FP7 airborne radar display tube, ca WWII. It has a fast blue phosphor that excites a slow yellow one. Blasted with electrons (or a flashlight) it will glow for several minutes. ftp://jjlarkin.lmi.net/4FP7.jpg John |