What is the oscilloscope equivalent to the hp34401a?

[pizzigri]

I’ve read lots of posts and even done a search, however there many conflicting answers and models, it’s a mess! So maybe let’s ask the question directly.
The HP34401a is basically the gold standard for size, price, performance and value, not counting reliability and repairability in desktop DMM - arguably contending this place with a Fluke and a Keithley, but let’s not delve too deep into this.
But.....
What would be “the” Oscilloscope, were the 34401 be one? Which brand, model etc would rightly take its place to the side of this venerable meter?

[Grandchuck]

Many, many possible answers and all of them right depending ...

Here is an interesting link:  http://www.oscopes.info/background/2265-oscilloscope-milestones

[rstofer]

I sure like the portable Tek scopes including my 485 but I would pay attention to the scopes that w2aew uses in his videos.  He works for Tek and can probably come up with any scope he wants.  Check his videos and check his scope course at the top of the Beginner's Forum.

If I didn't already have the Tek 485 and Rigol DS1054Z, I would be looking at the Siglent SDS1104X-U
https://www.eevblog.com/2020/12/16/eevblog-1355-new-siglent-sds1104x-u-399-4ch-oscilloscope-teardown/
or SDS1104X-E
https://www.amazon.com/s?k=siglent+sds1104x-e

I have no idea what the difference is between the -U and -E and I would probably try to get forum user Tautech to set me straight.

ETA:  After a wee bit of research, I wouldn't give up features from the -E to save money on the -U

https://www.electronicdesign.com/markets/press-release/21211152/saelig-saelig-releases-economy-4channel-100mhz-siglent-sds1104xu-oscilloscope

[BrokenYugo]

It really depends what you want/need it for. Scopes, especially DSOs, are far more complicated and varied in features and specifications than DMMs, so there is no go to "best" oscilloscope and probably never will be.

That said, I think the best bang/buck right now is the SDS1104X-E if you don't know what you need and just want a relatively low cost general purpose DSO you won't run into the limits of for a long time, if ever.

[oPossum]

What would be “the” Oscilloscope, were the 34401 be one? Which brand, model etc would rightly take its place to the side of this venerable meter?

Agilent 54622D

[Wallace Gasiewicz]

I am with rstofer.
As far as analog scopes go, I think the Tek 465, 475, 485 scopes are probably the "Standard really good scope"
I have the 475. The higher end old Tek scopes that are plug in module designs are really good and sought after but probably not in the correct ballpark.

As far as digital scopes, I really have to profess some ignorance as I only have one and have owned only one other. I do think however there probably is not current "Standard" and may not be one on the horizon. They keep adding features, some very nice and some not so useful. I am still getting used to mine.
What can be done digitally in what is called a scope at present makes them very different from the analog scopes.
Do you judge a digital scope by it Fornier transform? Just an example.
Different users expect different functions and these functions are not standard functions that were available in analog scopes.
So, unless everybody decides which functions are important and buys one brand or model of scope (not likely, anytime soon) these instruments will keep evolving, hopefully for the better.

[bdunham7]

What would be “the” Oscilloscope, were the 34401 be one? Which brand, model etc would rightly take its place to the side of this venerable meter?

The 34401A was produced over about a 25 year period, which is part of what makes it the classic that it is.  However, that 25 years was also a period of astonishing advances in oscilloscopes, so while a 34401A might still be a an excellent, competitive precision DMM even today, any of the scopes from that period are functionally obsolete by modern expectations.  Also, good scopes from that era would have been much, much more expensive than the 34401A, so it is really difficult to define one as being 'equivalent'.  If you want a scope mate to the 34401A from its early days and are willing to limit yourself to an analog scope priced anywhere near the ballpark of the 34401A, then perhaps the Tek 2235A might be a good fit--compact, good performance, repairable, reliable, etc.  If you want a modern pair, the last model Keysight 34401A and the DSOX1204G perhaps?

[pizzigri]

Agilent 54622D

Just watched Dave’s video on that and it’s quite nice!
It also helps that they built lots and not too difficult to find one. I had chosen the Siglent 2000 x plus series ( for hackability) as modern scope to replace the 1202x-e I got, but was really intrigued by these class of older scopes.

[pizzigri]

The 34401A was produced over about a 25 year period, which is part of what makes it the classic that it is.  However, that 25 years was also a period of astonishing advances in oscilloscopes, so while a 34401A might still be a an excellent, competitive precision DMM even today, any of the scopes from that period are functionally obsolete by modern expectations.  Also, good scopes from that era would have been much, much more expensive than the 34401A, so it is really difficult to define one as being 'equivalent'.  If you want a scope mate to the 34401A from its early days and are willing to limit yourself to an analog scope priced anywhere near the ballpark of the 34401A, then perhaps the Tek 2235A might be a good fit--compact, good performance, repairable, reliable, etc.  If you want a modern pair, the last model Keysight 34401A and the DSOX1204G perhaps?

Yeah I did not take that into consideration- you are right of course, and it made me think: the thing is I do not see a lowering of prices even for completely clunky and really marginal dso by today’s standards, and it puzzles me.

[David Hess]

The 34401A was produced over about a 25 year period, which is part of what makes it the classic that it is.  However, that 25 years was also a period of astonishing advances in oscilloscopes, so while a 34401A might still be a an excellent, competitive precision DMM even today, any of the scopes from that period are functionally obsolete by modern expectations.

The list of oscilloscopes which were that long in production is pretty short.  The Tektornix 7603 mainframe oscilloscope was in production for 18 years, and still has desirable features and functionality, but later instruments, and especially DSOs, had shorter production runs, and they were all expensive.  The 2430A series of DSOs, which I think are the oldest DSOs with automatic measurements, were in production for 12 years.

A better measurement might be how many were sold, but this is more difficult to determine.

Going be features and innovation, then the Tektronix 545 series of tube oscilloscope is a classic and it was produced for 19 years.

[SilverSolder]

The 34401A was produced over about a 25 year period, which is part of what makes it the classic that it is.  However, that 25 years was also a period of astonishing advances in oscilloscopes, so while a 34401A might still be a an excellent, competitive precision DMM even today, any of the scopes from that period are functionally obsolete by modern expectations.  Also, good scopes from that era would have been much, much more expensive than the 34401A, so it is really difficult to define one as being 'equivalent'.  If you want a scope mate to the 34401A from its early days and are willing to limit yourself to an analog scope priced anywhere near the ballpark of the 34401A, then perhaps the Tek 2235A might be a good fit--compact, good performance, repairable, reliable, etc.  If you want a modern pair, the last model Keysight 34401A and the DSOX1204G perhaps?

Yeah I did not take that into consideration- you are right of course, and it made me think: the thing is I do not see a lowering of prices even for completely clunky and really marginal dso by today’s standards, and it puzzles me.

Basically it is due to an inefficient market.   If the market was truly efficient (buyers were all fully educated and able to correctly appraise the value of an item) the price levels would be closer to scrap for many older models, perhaps a little higher due to collectibility value....

[David Hess]

Basically it is due to an inefficient market.   If the market was truly efficient (buyers were all fully educated and able to correctly appraise the value of an item) the price levels would be closer to scrap for many older models, perhaps a little higher due to collectibility value....

But fully educated buyers know how to make the best use of old test instruments, and know what capabilities they have that modern instruments do not.

[SilverSolder]

Basically it is due to an inefficient market.   If the market was truly efficient (buyers were all fully educated and able to correctly appraise the value of an item) the price levels would be closer to scrap for many older models, perhaps a little higher due to collectibility value....

But fully educated buyers know how to make the best use of old test instruments, and know what capabilities they have that modern instruments do not.

Ssssssshhh, I'm trying to get the prices of cool old gear down! 

[tggzzz]

Basically it is due to an inefficient market.   If the market was truly efficient (buyers were all fully educated and able to correctly appraise the value of an item) the price levels would be closer to scrap for many older models, perhaps a little higher due to collectibility value....

But fully educated buyers know how to make the best use of old test instruments, and know what capabilities they have that modern instruments do not.

Ssssssshhh, I'm trying to get the prices of cool old gear down! 

David Hess is spot on, of course.

I'm surprised nobody has mentioned the Tek 2465 scopes. They are very good, except that they only have 1Mohm//20pF and 50ohm//20pF inputs.

The Tek 485 has a true 50ohm input (and a 1Mohm//20pF input).

Now, anybody want my spare 2465?

[SilverSolder]

Who buys stuff like this (eBay listing):

HP/Agilent/Keysight 3325A Synthesizer/Function Generator w/Opt. 001 & 002
Pre-Owned
$2,169.99 Buy It Now + $206.45 shipping

[w2aew]

If we're going to go by duration of production, and popularity in terms of number of units sold, in the Tektronix line it would have to be the TDS3000 series of scopes - very long production run, and the highest volume seller as far as I recall.  In fact, Tek really wanted to replace it many years before it did, but customer demand kept it in production far longer than was ever intended.

[Cerebus]

Who buys stuff like this (eBay listing):

HP/Agilent/Keysight 3325A Synthesizer/Function Generator w/Opt. 001 & 002
Pre-Owned
$2,169.99 Buy It Now + $206.45 shipping

Plenty of people, just not at that crazy price. I've got a 3325A that I bought a couple of years ago. I don't remember exactly what I paid for it, but it was under £200 delivered.

[Cerebus]

What would be “the” Oscilloscope, were the 34401 be one? Which brand, model etc would rightly take its place to the side of this venerable meter?

Agilent 54622D

I think that's probably quite a good candidate to fill the same spiritual oscilloscope niche as the 34401A does for multimeters. In fact I'd say that the only thing stopping it from being a good workhorse scope even nowadays is the limited sample rate and memory depth compared to modern scopes. In a similar vein, the literal successor to the 34401A, the 34461A has a much higher memory capacity and would make more readings a second than the 34401A if it hadn't been deliberately hobbled to reserve that capability for the next two models up the range.

[SilverSolder]

Who buys stuff like this (eBay listing):

HP/Agilent/Keysight 3325A Synthesizer/Function Generator w/Opt. 001 & 002
Pre-Owned
$2,169.99 Buy It Now + $206.45 shipping

Plenty of people, just not at that crazy price. I've got a 3325A that I bought a couple of years ago. I don't remember exactly what I paid for it, but it was under £200 delivered.

I have several of them, LOL.  Big fan of them.  I specifically meant the price.  You'd have to be a member of the set (Uninformed, Crazy, Don'tCare) to pay almost $2.4K though...

[SilverSolder]

What would be “the” Oscilloscope, were the 34401 be one? Which brand, model etc would rightly take its place to the side of this venerable meter?

Agilent 54622D

I think that's probably quite a good candidate to fill the same spiritual oscilloscope niche as the 34401A does for multimeters. In fact I'd say that the only thing stopping it from being a good workhorse scope even nowadays is the limited sample rate and memory depth compared to modern scopes. In a similar vein, the literal successor to the 34401A, the 34461A has a much higher memory capacity and would make more readings a second than the 34401A if it hadn't been deliberately hobbled to reserve that capability for the next two models up the range.

You would need to go all the way up to a 3000 series modern Keysight scope ($4K+ range) to equal the 2 analog + 16 digital channel MSO capabilities of the 54622D.   If you don't need high bandwidth, it is still a great bang for the buck at a used price of 5% - 10% of that...