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For about a week, just after the most recent Firefox update, I've experienced hangs and slow-loading on some sites. So I opened the No-Script dialogue and killed everything "google" or "rubiconproject". Now quite fast and very few ads of any kind. ...Jim Thompson

Oh, and it's sold as a 200 MHz scope, but it really isn't.

What's a good ANALOG scope now-a-days? 100-200MHz is adequate for my G-job needs. My old Leader LBO-325 has lost its focus and, at 29 years old, it'd probably cost me more to refurbish than to buy new. ...Jim Thompson

I'd never use an analog scope again. All the traces are the same color!

The 100 MHz Rigol is a great scope.

Thanks! I also have one of those cheapy Tek things with annoying menus :-( I like knobs ;-) ...Jim Thompson

--- Once upon a time, Tektronix made an analog oscilloscope where the trace colors varied by virtue of a variable strength electron beam and a layered phosphor penetration CRT.

JF

I did some circuit designs for Tek, way back in their "American" days... on a storage scope scheme. ...Jim Thompson

Get a Tektronix 2465, best analog scope ever made. If it doesn't have to be portable and you've got the space then buy a Tektronix 7000 series mainframe, that's what I use. Anything less falls under the category "toy".

The only company that I know of that still makes high-BW analog scopes is Iwatsu but they cost as much as a small car:

There is stuff one simply cannot see with a digital scope.

I still have my HP 1725A. Two actually. Why, I don't know, since I use the DSO Teks or the Rigol if I need a scope I can actually move.

Surely you can find a Tek 465 used. The HP analog scopes were used by Intel in the valley, so a ridiculous number of them are floating around. But the Tek 465 was probably one of their best selling scope.

I like those Tek 7000 scopes, and they are really cheap used. But the mainframes are old. That is one reason you find so many plugins on the used market. The mainframe croaks, costs a fortune to fix, so they dump the plugins and move on. My Tek 11402A with two 4 channel plugins and one differential was cheap, simply due to the boat anchor nature. Something like $180 at the old Livermore swap meet. Well $180 plus a backache.

The 7904 was really nice.

I have a 7704A. It had some issues in the power supply but so far that was it. Works fine now. Crispy clean trace on the CRT. When it's really dark it has a blueish after-glow that lasts for hours into the night.

People have reported popping tantalums but I haven't had that happen yet. That would be a lot of disassembly work to fix but I'd do it. Mainly because other than a Tek 2465 you can't buy this level of performance anymore.

Just in case I also have a Telequipment scope on a shelf. I can't imagine being without an analog scope.

We have a bunch of Tek 11801 sampling scopes that have color CRT displays. They are magnetic deflection, vertical raster scan, shadow-mask tubes.

Once Tek had a color display with a monochrome tube and a liquid-crystal color gating thing in front.

There's far more stuff you can't see with an analog scope!

Go with the 475. It is very much similar to the 465 but does 250 MHz BW. Look for S/N > B250000 for a little better build.

Am 15.01.2014 22:56, schrieb Joerg:

I still have a 200 MHz 4 Ch. Iwatsu that I bought anew for DM 11,000

• VAT. Must be close to 25 years old now. 10 years ago it had a defective to-5 transistor in the x-deflection, circuits are in the manual, so I could repair it myself.

In december I found that it now has a focus/astigmatism problem. When I get some time, I'll try to repair it again.

Nevertheless, for daily use it has lost completely against a 2.3 GHz / 8 GS Agilent 548??A with 2.5 GHz FET probes. Sorry, no contest.

and even more one cannot see with an analog one. Remember that

regards, Gerhard

Am 16.01.2014 00:27, schrieb John Larkin:

You beat me by 2 minutes!!!

:-) Gerhard

Sure, like data glitches. In the old days I could make do with the logic analyzer but a DSO makes this a bit easier.

But when it comes to weird behavior in RF power stages or switch mode supplies DSO do not cut it. Sometimes all you have is a pulsating subtle thickening of fuzz during a transition. DSOs can't handle that. There were many times I hauled dusty old analog scopes out of closets and basements at clients and it was "Shazam, there's the problem!". Or when I urged one client to buy a Tek 2465 as their first analog scope. The engineer later said that was like someone turned on the high beams.

Reminds me of a (back then) expensive HP scope I borrowed at Aachen University from the semiconductor guys. Was happily scoping around and ... phhhht .. *POP* ... smoke came out. Oh no! Luckily it was also only a transistor in the power supply.

Depends on what you are doing. I guess you are more into RF stuff in the GHz range. For me it has become lots of switcher designs and re-designs. Not that it's my facorite turf but there just is lot of help needed these days. Nasty EMC, noise or jitter problems are almost impossible to diagnose without a good analog scope. But it has to have well north of

I don't think I ever used that one.

I think he is referring to the 7103/4 scope mainframe with the micro-channel plate in front of the screen. They timed the intensity to limit any burn-in of the MCP.

The CRT in that scope could actually do more than 3 GHz if you fed directly into the deflection plates. Remember, this was >20 years ago. There wasn't much that could touch it at the time.