A good digital oscilloscope?
in [Design]
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From: George Herold on 8 Dec 2009 09:13 On Dec 7, 6:28 pm, John Larkin <jjlar...(a)highNOTlandTHIStechnologyPART.com> wrote: > On Mon, 07 Dec 2009 11:56:59 -0800, qrk <SpamT...(a)spam.net> wrote: > >On Sun, 06 Dec 2009 20:29:24 -0800, John Larkin > ><jjlar...(a)highNOTlandTHIStechnologyPART.com> wrote: > > >>On Sun, 6 Dec 2009 22:18:04 -0600, "Tim Williams" > >><tmoran...(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. > > John- Hide quoted text - > > - Show quoted text - Hee Hee, Yeah once they figured out to put colored 'voltage' knobs that match the color on the display I became a digital scope fan. George H.
From: John Larkin on 8 Dec 2009 10:00 On Tue, 08 Dec 2009 12:42:41 GMT, Jan Panteltje <pNaonStpealmtje(a)yahoo.com> wrote: >On a sunny day (Mon, 07 Dec 2009 20:21:56 -0800) it happened John Larkin ><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote in ><upkrh5lpbge5a690oth9tsaqp7san0nnj6(a)4ax.com>: > >>>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 > >Nothing special, my DVD remote does the same: > ftp://panteltje.com/pub/DVD_remote_fluorescent_buttons_img_1676.jpg Try some strontium aluminate. It's something like 10x better a light storage thing than the old ZnS stuff. John
From: Jan Panteltje on 8 Dec 2009 10:54 On a sunny day (Tue, 08 Dec 2009 07:00:51 -0800) it happened John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote in <aeqsh5lt88otd57hp85t72m4o02ig3f6nh(a)4ax.com>: >On Tue, 08 Dec 2009 12:42:41 GMT, Jan Panteltje ><pNaonStpealmtje(a)yahoo.com> wrote: > >>On a sunny day (Mon, 07 Dec 2009 20:21:56 -0800) it happened John Larkin >><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote in >><upkrh5lpbge5a690oth9tsaqp7san0nnj6(a)4ax.com>: >> >>>>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 >> >>Nothing special, my DVD remote does the same: >> ftp://panteltje.com/pub/DVD_remote_fluorescent_buttons_img_1676.jpg > >Try some strontium aluminate. It's something like 10x better a light >storage thing than the old ZnS stuff. > >John The DVD remote in the above link *is* strontium aluminate, I just did the 4 minute test, http://en.wikipedia.org/wiki/Phosphorescence (scroll down) still clearly visible, not adapted eyes, also after 5 minutes. The color also matches tha tbird... They say the ZnS stuff is no longer used... The real 'hot' stuff I remember from my youth was 'radium', radium on watches, clocks, and even on some light switches. That was all no longer allowed at some point.
From: John Larkin on 8 Dec 2009 13:28 On Mon, 7 Dec 2009 22:21:43 -0600, "Tim Williams" <tmoranwms(a)charter.net> wrote: >"Jamie" <jamie_ka1lpa_not_valid_after_ka1lpa_(a)charter.net> wrote in message >news:oFhTm.36236$kY2.31856(a)newsfe01.iad... >> 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. > >486 is on my Wish List. And 2465. Yessss, my preciousss.... > > >Tim I love our TPS2024. 200 MHz, and all four channels and the trigger input are fully floating. Wanna clip the probe ground lead onto the source of a fet that's flailing 400 volts off ground? No problem. John
From: Tim Williams on 8 Dec 2009 13:32
"John Larkin" <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote in message news:oh6th5903d58sogu3cj8vk3er6r6li9m32(a)4ax.com... > I love our TPS2024. 200 MHz, and all four channels and the trigger > input are fully floating. Wanna clip the probe ground lead onto the > source of a fet that's flailing 400 volts off ground? No problem. Tasty. What's C-to-ground like, is it basically a differential input (2 x 1M || 20pF) with a BNC input? Tim -- Deep Friar: a very philosophical monk. Website: http://webpages.charter.net/dawill/tmoranwms |