I need a new oscilloscope - 300€?

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I'm looking at a Tek 2430a for sale locally , 95 euros , appears to be in good condition
It seems to be the only model in the 2400 series thats digital , 8bit,
its still a CRT scope but has some extra measurement features .
It dates from the late 80's early 90's.
The Tek 2400 series seem to be maybe the best analog scope you could find and come with lots of recomendations but does the 2430a pose any limitations due to it being digital 8bit ?
Just looking around the 2430a seems to have certain issues that crop up , I guess it was new technology at the time and maybe not as reliable as the rest of its siblings in the range . any input welcome .
I don't know this particular one, but it looks to me like you would have the cons of CRT (bulk) and digital (not adequate for observing glitches), and only a few of the pros of digital.
8-bit is definitely a good reason for avoiding it.
 
I haven't tried it but I haven't read the best comments about these scopes. I guess there's a reason why 12-bit scopes cost thousands of $$.
A Friend brought over a hand held DMM/Scope combo from this company the other day. I checked ACV accuracy and it wasn’t very good. I believe 1.228VAC as measured against an AP P1 and a Fluke 287 measured 1.246VAC. I didn’t look at the scope but I assume it was as bad.
 
A Friend brought over a hand held DMM/Scope combo from this company the other day. I checked ACV accuracy and it wasn’t very good. I believe 1.228VAC as measured against an AP P1 and a Fluke 287 measured 1.246VAC. I didn’t look at the scope but I assume it was as bad.
Historically, oscilloscopes were not precision instruments. A CRT could drift by almost 5% over a couple of hours. It's only when they integrated digital displays that they started to be more accurate.
 
Recently Ive been making up new adapter cables for my multimeter to allow better AC measurements , standard multimeter test leads are not very usable . One cable I made is an XLR to 4mm bannana plugs , cable sheild is connected in the XLR only and +/- go directly to the red and black terminals on the meter . For unbalanced audio Ive repurposed an old scope probe with a BNC to dual 4mm bannana adapter along with a selection of other adapter cables for phono /unbal jack etc . Im getting much more reliable results. Ultimately noise floor ,audio bandwidth and distortion measurements will be done with the soundcard and REW ,
Im wondering do I really even need a digital scope for measurement at all . As I mentioned I missed a Fluke 92b scopemeter for sale cheap recently , along with the 187 multimeter and REW I think I would have been more or less covered for what I need . An old fashioned analog scope takes up lots of bench space and may have accuracy/calibration issues due to age/design but as Abbey mentioned its still invaluable for certain fault finding tasks that a digital scope doesnt have a hope of catching. For the purposes of calibration of REW at least one accurate measurement device is needed ,the Fluke 187 with appropriate test cables/probes is as accurate as I need , and by the looks a lot more accurate than typical lower budget digital scopes .

Below is a pic of some of the cables , as you can see the BNC to dual bannana plug I cobbled together myself from an inline BNC socket and a couple of 4mm plugs , capacitance is a little higher than we might want at 12 pf due to the proximity of the 4mm plug to the inside of the body of the connector , works well enough though.
 

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Hi!

I'm about to buy a scope for troubleshoouting noises and oscillations in mic preamps 9K, etc.. 10/25Mhz? enough bandwidth?. I also have an old windows7 laptop with cubaseSX3, for recording audio. Tabletop or pc based scope? Also I may need to perform some frequency sweeps, to adjust filters or test the frequency response. I found some Multicomp scopes at Farnell:

https://es.farnell.com/multicomp-pro/mp720016-eu-uk/osciloscopio-pc-2-1canales-25mhz/dp/3107575
and also the classic picoscope 2204A:

https://es.farnell.com/pico-technology/picoscope-2204a/oscilloscope-pc-10mhz-with-awg/dp/2365425

Farnell also has some bench scopes from multicomp (their brand), 2 channels, but no signal generator...

https://es.farnell.com/multicomp-pro/mp720009-eu-uk/dso-2-canales-20mhz-10kpts-100msps/dp/3107568
¿Are all these minimally good enough?

Jay x
 
Tabletop or pc based scope?
My position is cheap digital oscilloscopes are not terribly good for audio.
The main reason is the latency. Let's say you use the probe to "sniff" signal. The trace will appear with a significant delay and stay on for some time (typically until a new signal comles to trigger the timebase).
This is a PITN.
I have a "vintage" analog scope that I don't use too often, but sometimes it is the perfectly adequate tool.
Most of the times I use a small and cheap 2.4" portable scope.
I still have a Pico, which is terribly disappointing. The absence of a real front end (with proper attenuator, switches and time base controls), being replaced by on-screen virtual controls is not for me. Maybe kids that are experts at texting on smarphones can deal with oit. I just can't. The Pico is used as a (poor) paperweight.
 
I have seen oscillations in the 25-50 MHz range in "audio" circuits. You would never know they are there using a 20 MHz scope, and some people may not care; if you can't hear it, it isn't there, right? But it is there and it burns power and it may have other affects. I always recommend 100 MHz as a minimum, but if you can get a good deal on a 50 MHz scope, go for it.
I agree with Abbey; analog scopes with real controls are so much more satisfying to use and generally work better than cheap digital scopes. The one exception is when you are hunting that elusive pop that only happens once every 5 seconds or so -- then digital is hard to beat. If you can drop 2-3K on a good digital scope, you will be completely satisfied.
 
I wouldn't insist on 100 MHz for general troubleshooting while better is better, a 20Mhz scope is better than no scope. In cases of above band oscillation there are often visible signs even if the scope can't follow the waveform perfectly.

JR
 
I’ve never used it for work yet but I got a good deal on this one.
Promises a lot!

https://www.amazon.com/Siglent-Technologies-SDS1202X-Oscilloscope-Channels/dp/B06XZML6RD/
I think that the popular Chinese scope brands are "fair", for example Rigol, Siglent, GW Instek, etc... I recently bought a GW Instek, much more expensive (circa $1000 USD ) because it includes spectrum analyzer, AWG, etc... and while the scope has a lot of great features and many advantages, all the cheap Chinese scopes have issues, for example, in this specific scope the line wont "zero" out perfectly, there is a slight offset, its minor and it only seems to be a visual offset rather than a real offset, but this is the sort of stuff you should expect from these scopes. With the Rigol scopes I have also seen and read many stories in which they state that they have problems displaying certain signals and you need constant updates to fix many of the problems, etc...

On the other hand, I have a Tektronix TBS1102 which I bought new from eBay some years ago for around $350 USD, it is a very crude and archaic scope, it has 1/100 the number of features that the new Chinese scopes have, the display is not very advanced, sample memory is extremely small, etc... but I've had ZERO issues with it, it is accurate, there are no software bugs and I fully trust it.

An example might serve to illustrate this better: around 8-10 years ago, a local college bought a new batch of Chinese scopes for some of the student labs, if I am not mistaken they were GW Instek, 4 channel, 200 MHz BW, with a big beautiful color screen. A professor from the Telecom department was trying to measure and show his students a high frequency FSK signal. After messing around for quite some time with the GW scope and not being able to get a good capture of the signal, he asked the lab tech to bring out one of the old Tek scopes. I am talking about an old 20MHz digital Tek scope, with a tiny B/W passive matrix display, slow as hell, etc... And the scope captured and displayed the image immediately even when the signal was well over the scope's bandwidth. Perhaps it wasn't the best image because the signal's frequency was quite higher than the max bandwidth of the scope, but something is better than nothing. So all the apparent extra features you get from a Chinese scope for the same price of a low end Tek scope are just that, "apparent".

Now, if you are just planning on using a scope as a "signal window" with sine waves, then, anything will work, in which case I would even argue that an analog scope is better, but I digress. The real difference is when you are trying to measure or view signal anomalies such as transitory events, etc... In those cases, the Chinese scopes—at least in my experience—have proven that they are not to be fully trusted...

I am not saying "do not buy them", I have a Chinese scope myself and I really like it, but, if I could only have one scope and I had to choose between a very low-end Tek VS a Chinese scope with many features which costs the same as the Tek scope, I would blindly choose the Tek scope.
 
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For many years i got by with '50s era 200KHz recurrent sweep single channel scopes. I think I had 4 of them go up in smoke before I bought a 20MHz Heathkit at a swap meet (which I had to go through and totally resolder). True enough, we all have budgets we must live within. (Almost) any scope is better than no scope, but a good used analog scope can be had for less than 300 Euro. IMO, that is a better deal than a cheap digital scope (and I have both) but I suppose I am biased toward what I grew up with.

Now, laugh with me: I have a Hantek scope that is loaded with bells and whistles, all of which work, but some work better than others. I was flipping through the menus one day, seeing which of these features were actually useful when I accidentally changed the language to Chinese! Fortunately I had been drawing a map through the menu tree as I did this, so I reset it to get to a known point, then was able get back to the language menu without too much trouble. Seeing Chinese appear on the screen was a real gut punch, thugh.
 
For many years i got by with '50s era 200KHz recurrent sweep single channel scopes. I think I had 4 of them go up in smoke before I bought a 20MHz Heathkit at a swap meet (which I had to go through and totally resolder). True enough, we all have budgets we must live within. (Almost) any scope is better than no scope, but a good used analog scope can be had for less than 300 Euro. IMO, that is a better deal than a cheap digital scope (and I have both) but I suppose I am biased toward what I grew up with.

Now, laugh with me: I have a Hantek scope that is loaded with bells and whistles, all of which work, but some work better than others. I was flipping through the menus one day, seeing which of these features were actually useful when I accidentally changed the language to Chinese! Fortunately I had been drawing a map through the menu tree as I did this, so I reset it to get to a known point, then was able get back to the language menu without too much trouble. Seeing Chinese appear on the screen was a real gut punch, thugh.
The advantage of owning an analog scope is that you actually learn how to use a scope, whilst those who learn with a digital scope are obsessed with the "auto set" button...
 
Thats the crappiest thing I've ever seen, but I guess that if it works for you, then its ok
 
The advantage of owning an analog scope is that you actually learn how to use a scope, whilst those who learn with a digital scope are obsessed with the "auto set" button...
Isn't that just a modern advanced version of "beam find"?:)

I still love my two Tek 2246 with readout and use them every day, digital scopes are very useful when I need to prepare measurements for articles, presentations, etc.
For new DIYers, I would recommend a better quality dual channel digital scope with a generator such as Keysight or R&S or similar (it's not a smartphone that you replace every year), and it's easier to publish problematic readouts on the forum and ask for help.;)
 
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