Author Topic: Help me decide for an analogue oscillosope  (Read 2916 times)

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Offline ramonestTopic starter

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Help me decide for an analogue oscillosope
« on: March 27, 2016, 01:20:45 pm »
Hello, I'm looking forward to get a decent analogue oscilloscope. Currently I don't have much free time because uni and stuff, but decided to spent some time during looking for the possible options, and here they are:

-Promax 20 Mhz 150€
-Hameg 203-7 150€ and gould 1604/104 250€ (They're from the same seller and he lowered the hameg from 250 to 150 but he's on vacation)
-Hameg analog digital scope HM305 120€
-Hameg 203 180€ He sold some and has good feedback and seems to know about it
-Tektronix 2221A 150€ He says it's all working and calibrated
-Hameg 1004 120€ It scares me he's no idea what he's selling he send me a video where he just powered it on and it picked some noise
-Tektronix 2225 200€ (it has a missing knob, a small one).

Is any of them worth buying? (I'll actualize the prize if i can get it lower.)
Any special opinions on the promax brand? is a brand I don't usually see on the internet but my uni seems to have a liking to it.
Naturally any advice is well accepted as well as any scope sale without an astronomic shipping price.

Ultimately I'd like to get the Rigol 1054Zbut since I don't have much time and I touch digital ones at uni I'm not hasty about it.
 

Offline tggzzz

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Re: Help me decide for an analogue oscillosope
« Reply #1 on: March 27, 2016, 01:48:19 pm »
You will need to define some constraints, especially your budget and what you will and won't use the scope for.

Some of those prices seem rather high. Do a sanity check by looking at ebay. If you are a beginner, be wary of buying anything other than a working scope.

You will get people saying "must be digital, must be DS1054Z". Ignore them. An engineer is someone that can do something for $1 that any fool can do for $10. An engineer will learn the capabilities of each tool, and will use ingenuity to make valid measurements with simple tools. That's fun and looks good on a CV, and is a good discussion point during interview.

If you are at school/university, see if they have equipment that you can use for your own projects, e.g. at night.
There are lies, damned lies, statistics - and ADC/DAC specs.
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Offline edy

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Re: Help me decide for an analogue oscillosope
« Reply #2 on: March 27, 2016, 04:04:50 pm »
Watch Dave's video on buying CRO's on eBay here:



I followed his advice and bought 2 nice scopes. The first a 20 Mhz "no name" (or extensively copied) for $50 delivered. My pride and joy is a 100 Mhz Hitachi with digital cursors for $80.

As for eBay, DO NOT get your mind set on any specific scope. Find one, set auto bid at max amount you are willing to pay and walk away. If it goes over, don't chase it. Another will come by. Be ready to pass up 4, 5, 6 or more scopes before winning an auction. Also don't get hung up on the popular brands like Techtronix and make the mistake to ignore many lesser known but good quality scopes.

And those prices you mentioned seem high to me. Rule of thumb is $1 per MHz or less.
« Last Edit: March 27, 2016, 04:20:54 pm by edy »
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Offline vasi_ro

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Re: Help me decide for an analogue oscillosope
« Reply #3 on: March 27, 2016, 05:31:55 pm »
From your list the best choise is Tek 2221A. The price it's ok and also you have a nice readout. On the negative side...this scope is not very user friendly reparable.. so make sure that you buy a working one.
Hameg are also good scopes but i think you can find them much cheaper compared to your list.
 

Offline ramonestTopic starter

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Re: Help me decide for an analogue oscillosope
« Reply #4 on: March 27, 2016, 05:39:49 pm »
You will need to define some constraints, especially your budget and what you will and won't use the scope for.

When I started I was thinking of a bit over 100 maximum for a working one. For now I'm not into high frequency/digital stuf.

Quote
You will get people saying "must be digital, must be DS1054Z". Ignore them. An engineer is someone that can do something for $1 that any fool can do for $10. An engineer will learn the capabilities of each tool, and will use ingenuity to make valid measurements with simple tools. That's fun and looks good on a CV, and is a good discussion point during interview.

Totally agree.

Quote
If you are at school/university, see if they have equipment that you can use for your own projects, e.g. at night.

I deem that impossible the only professor that seemed to have some interest in helping told me that he could try to help me troubleshoot if I took something there I did and he didn't get up from his chair or even touched it. And well, I prefer to be able to do it by myself and to know how to rather than being annoying around there.
 

Offline ramonestTopic starter

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Re: Help me decide for an analogue oscillosope
« Reply #5 on: March 27, 2016, 05:45:49 pm »
From your list the best choise is Tek 2221A. The price it's ok and also you have a nice readout.

It was my fav too. It includes 1 probe and manual user too.

Quote
On the negative side...this scope is not very user friendly reparable.. so make sure that you buy a working one.

Does it has something to do with it not being a full analogue scope? Would Hameg hm1004 and hm305 have the same problem?


If I can get a similar price on the Tektronix 2225 and that it's properly working aside from the missing know, I thought it might be a more solid one is it true? (The seller told me he's on vacation he'll contact me next week).
« Last Edit: March 27, 2016, 05:53:54 pm by ramonest »
 

Offline ramonestTopic starter

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Re: Help me decide for an analogue oscillosope
« Reply #6 on: March 27, 2016, 05:51:20 pm »
Watch Dave's video on buying CRO's on eBay here:

I obviously did. But is not as easy as he says to get a working one for 50€ (which are more than $50). At ebay.com maybe but to ship it to EU costs way too much... And I found people that don't even know what they sell (one was saying that he was selling a current measurer that "powered on" but he didn't go lower than 200...)
 

Offline tggzzz

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Re: Help me decide for an analogue oscillosope
« Reply #7 on: March 27, 2016, 06:01:34 pm »
As a beginner, you really don't want to be going around inside a scope. Typical faults are circuits operating at -2500V, and there is +18,000V elsewhere - both with sufficient charge to kill you.

Avoid anything that "powers on", unless you are prepared to get it and then junk it. Look for scopes displaying a good proper trace; if they don't there's often a good reason.
« Last Edit: March 27, 2016, 06:27:11 pm by tggzzz »
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
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Offline grouchobyte

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Re: Help me decide for an analogue oscillosope
« Reply #8 on: March 27, 2016, 06:21:00 pm »
As a beginner looking for a good analog scope, I would steer you towards anything Tektronix circa 1990 and earlier. For a very long time no one was better at making scopes, including HP. I know this because I worked at HP and we used to joke about HP stuff and how it sucked compared to TEK scopes.

That said, there are many good scopes today, including digital ones and many brands to chose from.
But if you can find a Tek 465, 475, 485 or a 2465 you will have a instrument that will outdo many modern boxes for years to come.

PS. I dont work for Tek anymore ( I did once upon a time) and my opinion may seem biased, but there is no denying they are the gold standard (or they were years ago) before they changed the management to a profit motivated quorum.


Best of luck
@grouchobyte
« Last Edit: March 27, 2016, 06:32:22 pm by grouchobyte »
 

Offline tggzzz

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Re: Help me decide for an analogue oscillosope
« Reply #9 on: March 27, 2016, 06:26:37 pm »
But if you can find a Tek 465, 475, 485 or a 2465 you will have a instrument that will outdo many modern boxes for years to come.

Worryingly I have a 465, a 485 and an HP1740a - all of which now work. To my surprise, internally the construction of the HP is far better than that of the 465.
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
Having fun doing more, with less
 

Offline ramonestTopic starter

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Re: Help me decide for an analogue oscillosope
« Reply #10 on: March 27, 2016, 07:45:01 pm »
As a beginner, you really don't want to be going around inside a scope. Typical faults are circuits operating at -2500V, and there is +18,000V elsewhere - both with sufficient charge to kill you.

Avoid anything that "powers on", unless you are prepared to get it and then junk it. Look for scopes displaying a good proper trace; if they don't there's often a good reason.

I'm really won't get one that doesn't at least show the selfcal properly on screen that's the main reason I didn't even show some options here, they say it works but when I ask them to show the cal at the screen and the controls at the same photo, they don't know what calibration means. But they won't go down on price either...
 


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