RLC bridge

=20

Sevrel opamp manufacturers have app notes on that. The older data sheets used to include test circuits for that test.

?-)

RLC

quite

It is sooo not a visual thing.

?-)

Be careful! Sounding like Martha Stewart..

every day,

Hi Jeorg,

The new R&S RTO scopes are nothing to do with the Hameg line AFAIK. Totally different beasts, different markets. The RTO are in the mid-high end TEK territory (say $20k-$50k).

Hameg do seem to have some reasonably priced test equipment. And not just scopes.

On a sunny day (Thu, 22 Mar 2012 12:25:12 -0700) it happened Joerg wrote in :

every day,

I have no idea, and no time to look up all those specs. If you like Hamag that is your thing, I do not. Religion or scope beliefs (or cars, or whatever, audio editors, text editors, programming languages, operating systems, etc etc), is not something worth fighting about. I just go by my feeling here. The wetware does not use logic in the known sense. hehe :-)

I like my Trio, and the fact that it still works means it is a good design. The best price performance digital scope is of course my PIC scope:

Soy Jorge, pero a veces tienen que leer documentos tecnicos en espanol.

every day,

It's just my gut feel that they didn't only buy Hameg for their product line but also for their engineering team. So you'll likely see new stuff come out and that won't bear the Hameg logo anymore, or even look like Hameg gear.

every day,

It would be an eye-opener. I don't think there is any scope that can compare, certainly not from Asia.

fighting about.

You don't seem to do too much analog stuff, and then you can use almost any scope. Since most engineers are in a similar position there aren't many analog or digital/analog combos out there anymore.

Well, I usually need to meassure stuff that's a lot faster :-)

On a sunny day (Fri, 23 Mar 2012 08:28:56 -0700) it happened Joerg wrote in :

Strange, PMTs, and now my decay experiment. Try it sometime.

Sampling, it can be extended easily. I prefer the analog scope for most things, including digital. The only advantage for a digital is that you can store data and do some math on it. For the rest it is noise, and did I mention noise, aliasing, and you never know if what you see is what you have.

There is also an other type of scope, in the seventies I designed one, it uses a normal 15625 Hz x 50 Hz display (teafee), and 2 window comparators. Imagine a H and V ramp (sawtooth) on the one input of the comparators, and the X and Y signal on the other.

With the correct DC bias on the inputs, if you OR the outputs of the window comparators, you get a square dot on the screen. Its a dot generator, used to be called 'trick box' in the old analog TV days. So the dot can now be moved around on the screen, way cool for huge displays to show students some stuff, slow of course. But if you connect it slightly different you get a 15 kHz sampled input waveform. I did it with some BFY90 transistors and diodes, and it could show a 500 kHz TTL waveform with all the little spikes on a 56 cm screen, and you could record it on tape too. Of course the waveform needed to be in sync, but the RF resolution was phenomenal say 5 MHz.. with just a few transistors. See how that works? Should have patented it,, I have some small PAL/NTSC LCD teafees coming, maybe I will do an other version. Analog, I could teach you a few things, Scopes? If you have a tek maybe my signature is on the calibration or QC. Hello. :-)

Well, and that you can view single-shot events for as long as you want rather than just the sweep duration!

Bah. On a contemporary DSO it's pretty hard to end up with bad data and not know that you're getting it. One could just as readily claim that on an analog scope you can never trust the amplitudes -- they're rolling off, after all, usually with a single-pole or thereabouts response, whereas on most DSOs the response is a more like a brick wall.

The "TV scope" idea sounds neat!

Nah, don't have much use for PMT gear right now. I am more at home in the RF world.

Very useful also if you suspect bus errors of the kind that a logic analyzer won't likely catch.

I experimented with TV scopes as well back then but didn't find it too useful. Too slow. The fact that the usual TV chassis was live didn't help either.

waveform.

record it on tape too.

phenomenal

But my old Hameg of the 70's already had much higher BW than that :-)

version.

Nope, has a red/silver cal sticker from Tek in Oregon.

DSOs have to major drawbacks:

Aliasing. That can especially fool younger folks. I've seen people pulling hair because their circuit spit out s..t. Or so they thought. I reached over, changed the time base and trigger and, voila, out came what they thought should come out. "I'll be darn!" was the typical reaction.

Sporadic low level noise. Sometimes an analog scope will show a wee bit of fuzz on a small sliver of the waveform, and it pulses. I've had cases where a digital scope was completely unable to display that. Just like "FFT-enhanced" spectrum analyzers can completely swallow signals that are clearly there.

Aliasing is a bitch. Which is why you should always buy a digital scope with peak-detect and keep peak-detect on.

Even then it's a bitch. Us older folks know this but nowadays some university professors think it is perfectly ok to let loose freshly minted engineers who have only read about scopes in some textbook footnote.

Quote "Programmable output peak-to-peak excitation voltage to a max frequency of 100 kHz"

That doesn't sound terribly useful.

day:

Well, I've only been in these nice digs for eight months or so, after doing a week a month in Albuquerque for a year and a half. (The place I was working was great, but 17 plane trips in one year is too much for Yours Truly.) They do dirt and rocks really well in New Mexico. ;)

Cheers

Phil Hobbs

On a sunny day (Fri, 23 Mar 2012 11:48:50 -0700) it happened Joerg wrote in :

waveform.

record it on tape too.

phenomenal

But could it store to video tape? I think not.

version.

Heerenveen.

On a sunny day (Fri, 23 Mar 2012 11:29:37 -0700) it happened Joel Koltner wrote in :

Sure single events, and events that happen at a low duty cycle, so you do not have to darken the room. There were good DSOs with storage CRTs for that though.

Yes it was really fun. One of those bright moments.. :-)

Yeah, but most DSOs today at around 5x or more relative to their bandwidth (e.g., 200MHz scope, 1Gsps or faster sampling) -- hence to alias you need to feed in a signal that's at least 2x or so above the scope's frequency range. I think the odds of a newbie doing that are less than the odds of a newbie seeing a, say, 400MHz analog scope, feeding in a 350MHz signal, and not realizing the amplitude is significantly incorrect.

OK, that's a good point -- many a cheap 8-bit DSO doesn't have as good of SNR as a good analog scope.

Yes, but just barely. :-)

---Joel