Author Topic: First Time With an Oscilloscope  (Read 2998 times)

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Offline spoonTopic starter

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First Time With an Oscilloscope
« on: March 02, 2017, 02:18:23 am »
Hi everybody.

I've been doing small time hobby electronics stuff for a while but just decided to finally delve into the world of oscilloscopes. I picked up a Tektronix 2211 from a surplus sale for $75. It seemed like a decent price but I could only do basic testing and it didn't come with probes, which I am now realizing can be quite expensive, so hopefully I didn't make a mistake. I fully intend to go through the videos in the "Oscilloscope training class (long)" thread but in the meantime, I just had a couple quick questions:

1) Would a simple function generator like this one from eBay https://goo.gl/aY5qL9 be good enough to just test that the scope is completely functional and play around with?

2) Would a cheap set of probes like these https://goo.gl/X29oTq be good enough just to do some beginner stuff?

Thanks!

(Attached a pic of the scope)
 

Offline Momchilo

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Re: First Time With an Oscilloscope
« Reply #1 on: March 02, 2017, 02:41:10 am »
Hi,
for the beginning the function generator and the probes would be enough. The scope has a very simple function generator built-in for probe adjustment. You find its output (the lug) to the left of the external trigger input. The first thing you could do without the probes, would be connecting a wire in one of the channel inputs (into the center pin) and attach the other end to this lug. There should shown up a square wave with 1kHz and 0.5V peak to peak. 
 
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Offline DimitriP

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Re: First Time With an Oscilloscope
« Reply #2 on: March 02, 2017, 03:38:05 am »
1 & 2, Yes & Yes
   If three 100  Ohm resistors are connected in parallel, and in series with a 200 Ohm resistor, how many resistors do you have? 
 
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Offline DimitriP

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Re: First Time With an Oscilloscope
« Reply #3 on: March 02, 2017, 03:41:59 am »
   If three 100  Ohm resistors are connected in parallel, and in series with a 200 Ohm resistor, how many resistors do you have? 
 
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Offline Brumby

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Re: First Time With an Oscilloscope
« Reply #4 on: March 02, 2017, 03:43:33 am »
... and watch this:

 
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Offline David Hess

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Re: First Time With an Oscilloscope
« Reply #5 on: March 02, 2017, 03:49:11 am »
Those probes will work fine and that function generator will provide lots of interesting signals to probe.
 
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Offline DimitriP

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Re: First Time With an Oscilloscope
« Reply #6 on: March 02, 2017, 05:59:45 am »
   If three 100  Ohm resistors are connected in parallel, and in series with a 200 Ohm resistor, how many resistors do you have? 
 
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Offline tautech

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Re: First Time With an Oscilloscope
« Reply #7 on: March 02, 2017, 06:48:52 am »
Those probes are the P6100 models that you can find almost everywhere and are perfect for your first set.
Experiment some with the 1x and 10x switching on them and learn how it affects the shown signal amplitude.
On 10x you have to do the maths in your head, say you display the Probe Cal signal on the front of the scope at 100mV/div, at a 1x probe setting it will display 5 divisions but with the probe set on 10x you'll have to have the input set to 10mV/div to see the same waveform. Easy.
Try to use the probes on 10x only unless you need more resolution than the input /div adjustments cater for.
This provides more safety against overloading the scope inputs with too high voltages that could damage the scope.

Good luck and have fun.
Avid Rabid Hobbyist.
Some stuff seen @ Siglent HQ cannot be shared.
 
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Offline james_s

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Re: First Time With an Oscilloscope
« Reply #8 on: March 02, 2017, 06:58:37 am »
The 2211 is a decent entry level analog scope, $75 is not an absolute steal but it's a perfectly reasonable price for the instrument provided the tube is bright and sharp and all the basic functions work. You don't need anything super fancy in the way of probes for a 50MHz scope, you should be able to find something for around 20 bucks or so. A function generator is handy but you could also build a simple oscillator out of something like a 555, or look for those little TTL oscillator cans to salvage out of scrap equipment. Lots of tutorials out there on how to use an oscilloscope, you should try to become proficient taking basic measurements of voltage and frequency. With an analog scope you have to calculate the frequency manually by counting the graticule marks for a complete cycle and working out the period from the time per division setting. It will make more sense once you sit down and try.

While you're waiting for a probe, you can get by with just a piece of wire poked into the input jack and another wrapped around the outside of the jack for ground to measure low frequencies.
 
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Offline spoonTopic starter

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Re: First Time With an Oscilloscope
« Reply #9 on: March 02, 2017, 04:18:32 pm »
Fantastic advice, thank you all! I'm looking forward to finally learning how to use a scope!

I can see this being a "gateway" thing. Next thing I know I'll be paying $1,000s for the latest and greatest.  :)
 

Offline David Hess

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Re: First Time With an Oscilloscope
« Reply #10 on: March 02, 2017, 07:04:12 pm »
The Tektronix 2211 has a lot to recommend it like the 500uV/div sensitivity, improved power supply from the 2225, and high resolution display.  Unfortunately unlike the older 2230/2232, it lacks equivalent time sampling, peak detection, and a delayed timebase.
 
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Offline james_s

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Re: First Time With an Oscilloscope
« Reply #11 on: March 02, 2017, 09:17:08 pm »
Seems like a solid choice for a new user though. It has enough features to be useful, without so many that it's overwhelming. Having used scopes for many years it's easy to forget how daunting that panel full of dials and switches can be to the inexperienced.
 
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