A good digital oscilloscope?

So, you're saying that you no longer fit into your wife's wedding dress... Perhaps it's all for the best :-)

"Tim Williams" wrote in news:hg3cc5$9r7$ snipped-for-privacy@news.eternal-september.org:

with triggered sweep,you also need holdoff,to block triggers until the sweep generator has stabilized. then you have end-of-sweep comparator,to tell the sweep logic the sweep has ramped all the way,so you don't get short sweeps.

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Jim Yanik
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"Tim Williams" wrote in news:hg3eqf$i8$ snipped-for-privacy@news.eternal-september.org:

It was just the natural progression to solid state,as transistors in those early days could not handle some of the voltages or fast speeds.

After all,the CRT was still a "tube",for a long time. now many scopes use LCD displays.

21.5 years at TEK field service centers,repairing and calibrating TEK scopes and TV test equipment.

--
Jim Yanik
jyanik
at
localnet
dot com

"Tim Williams" wrote in news:hg3l20$kf0$ snipped-for-privacy@news.eternal-september.org:

well,those tube monsters had REAL switches in them!

to use a scope these days,you have to go through menus.

Pretty soon,all TEK scopes will be made in China. (they're moving production there)

--
Jim Yanik
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Yeah, they put them in bizarre places, like double cascodes... the transistor has "no" voltage across it, so it can do fairly good bandwidth, while somehow amplifying the signal below it (in voltage terms I suppose). And other circuits altogether weirderer.

"No" voltage is a lie, of course, because tubes have far less transconductance than BJTs. A tube cascode is rather squishy, so the transistor would still have some ways to go in terms of voltage gain. It might operate on a fairly adequate loadline as far as making real power (delta V * delta I).

I like how the late model plugins ran from the same +/-150V or whatever supply they gave them, but almost all of that was pure resistor: they ran ~15V zener regulators off them instead. The equivalent transistor circuit used exactly as much current, with a tenth the voltage, and gave at least as much bandwidth. It's interesting how tubes operate with similar impedances and capacitances as transistors (within an order of magnitude), with less gain and about 10 times the voltage wasted.

Tim

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Deep Friar: a very philosophical monk.
Website: http://webpages.charter.net/dawill/tmoranwms

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What in tarnation is wrong with you? That front panel layout is entirely= =20 sensible for the design constraints. So is the SS/tube hybrid circuitry = for=20 the era. Yesteryears transistors are not today's transistors.

No probes, but yes it does have option 1M.

A picture as well, if you're interested:

You can email me at 66gtojayw AT comcast.net

On a sunny day (Mon, 14 Dec 2009 11:13:37 -0500) it happened JW wrote in :

What a piece of shit. Colored knobs were probably too expensive. the labeling is hardly readable. The waveforms look bad.

is past

Thing is, sync-scopes typically do not have any trigger signal fishing circuitry. They were budget scopes where that would have been too expensive. However, I've repaired tons of TV sets with mine. And ham radio gear, and class mate's digital circuits, and so on. Lo and behold the old scope still works.

My Hameg is fully "transistorizated" :-)

--
Regards, Joerg

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On a sunny day (Mon, 14 Dec 2009 09:27:13 -0800) it happened Joerg wrote in :

Was Hameg a sync scope? I have seen them, but did not like them. I designed and build my second scope in the end of the sixties, it had RTL logic, a delayed timebase, full trigger, but of course the bandwidth was limited. All solid state of course, Think I gave it away, just before I started travelling the world...

I do remember it used a 710 comparator for the TV trigger... TV video output transistors for the deflection, nice 10 turn pot for the timebase delay. You needed dual timebase to get a good look at the vertical TV interval, especially when doing things with video recorders. The whole thing was on one 10ox160 mm Eurocard...

Also build a transitor TV one such eurocard in those days...

Those are actually pretty good scopes. What good does a colored knob do? The knobs on mine are all gray and I'm happy with that. As for the labeling maybe you need to see the optometrist for some new glasses, or maybe it was the Beerenburger :-)

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Regards, Joerg

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I've use the scope. Seems fine to me. I have to laugh about the complaint of bench top space it uses. I don't own anything that compact. ;-)

I'm not sure if this is still the case, but IIRC, didn't Tek mux their ADC, while HP had an ADC per channel? So you use 2 channels, you get half the bandwidth.

Not sure but most scopes do that. That's ok with me because if you really need to measure a signal in great details it is very rare that it can't be done in single-channel mode. It's like with laptops, when do you really, really need the horsepower of that dual-core?

And no, games don't count :-)

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Regards, Joerg

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The way MS windows operates, I don't think any one gets efficient use of it anyways.. I have seen other OS'es really benefit from multicores.

Not so sure. On this PC the processor shows up as two processors in the control panel. When I run SPICE and then start something hefty in another window the sim doesn't slow down. On the non-dual PC it does, big time.

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Regards, Joerg

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You're seeing CPUs go to multiple cores because the ability to just keep cranking the clock rate has largely petered out. Hence you might as well ask, "When do you really need the horsepower of a 1GHz CPU?" :-)

I'd say that any simulation you run today that takes more than a few seconds can benefit significantly from multiple cores -- if they can be made inexpensively enough, of course. I like John's idea that eventually we might have, e.g., a 1000 core CPU that would be fast enough to let you tweak component parameters and end up with a complete SPICE simulation including monte carlo analysis done in effectively real-time.

---Joel