Best oscilloscope choice?

[TinselKoala]

What I want to do is to built a Hartley oscillator circuit, and I want to check if the real frecuecy of this circuit matches with the thorical one already calculated. It something very simple compare with most of the things I can find in forums abut electronics. So Will I need to channels for that anyway? I guested he meant to compare the signal of my circuit with a given "control" signal. Am I wrong?

Yes, for your one specific project you may just need to display a single waveform. And I frequently only need to look at a single waveform myself. I can also get to the store just fine by skipping down the block on one foot!

A scope is a major investment. Money, time, benchspace, learning to use it. And it is the "king" of test equipment. You will encounter many many cases when you want to see the effect of one signal (like a pulse generator output) on another signal (like the response of a RCL tank circuit) or you need to look at two output values like voltage and current simultaneously to determine a power curve. You will find two channels useful in your simple Hartley oscillator work as well. So don't even think about getting a single-channel scope as your primary instrument. It will be hard to find a decent single-channel scope anyway! (I have one, the Tektronix RM503..... it's a classic antique, a precision _low frequency_ oscilloscope that I use mostly for displaying Lissajous patterns in x-y mode).

Another issue is bandwidth. Your scope should have a bandwidth that is comfortably higher than the base frequency of the signals you will be measuring. The reason for this is so that you will see transients and proper waveshapes for signals other than sinusoidal, as they contain higher-frequency components. So if you intend to measure, say, signals in the 5 MHz range you probably need a 20 MHz scope for good accuracy.
The Hantek scope you posted at first will probably fill all your needs for some time, and at the price, under 100 dollars, it isn't too much to risk.

I am sure it comes with all the manuals you will need, and in fact you can download the manual here:
http://www.electronicaestudio.com/docs/Hantek6022BE_Manual.pdf

The ad says it comes with probes and the software including a LabView version. The manual says you need Windows XP/Win7. I've had a look at the manual, it seems clear and complete.

I can't think of a reason why you shouldn't get the Hantek. I haven't seen any customer reviews, but Hantek is a known company and has a lot of products in the field. If your computer can handle its modest requirements.... then Go for it!

And have fun...
--TK

ETA: I found this:
https://www.youtube.com/watch?v=m1WVZf5cuQE

[watari]

TinselKoala, I think you are right. I mean, you convinced me. I had my concerns and doubts because, as I told at the beginning, I'm kind of lost in this issue. I think you are right and this Hantek one is a good bet for my first oscilloscope. I'll go for it and I'll tell you all guys, how it is going.

BTW, thanks for the manual and the video.

[Pirate88179]

http://www.ebay.com/itm/Hantek-6022BE-PC-Based-USB-Digital-Storag-Oscilloscope-2-Channels-20MHz-48MSa-s-/271265189899

Here is a Hantek scope on ebay for $68.50 USD.  That sounds like a decent price.  I doubt if my pc could handle it though.

Bill

[Paul-R]

http://www.ebay.com/itm/Hantek-6022BE-PC-Based-USB-Digital-Storag-Oscilloscope-2-Channels-20MHz-48MSa-s-/271265189899

Here is a Hantek scope on ebay for $68.50 USD. 

I notice that it is 20MHZ and 48 Million samples per sec.

How do we work out what specification is needed?

[watari]

Hi everyone and (late) merry Christmas.

Eventually I got that Hantek 6022be oscilloscope for Christmas . Thanks for all of your advice, guys. I think it is a good acquisition. it is very easy to install and the use of its software is very intuitive, likely very simple but for me it is good enough so far, although it has things that are kind of improvable, as for example it shows a constant noise of a few mV.

Anyway, I've been playing with it and the circuit I built (a circuit that generates a signal of 1MHz based on a Hartley oscillator) and i realised about something quite curious.
When I use my Hantek oscilloscope in my plugged laptop, the Hantek oscilloscope's diode shows a patern like this: green-green-green-red (which I still don't know what it means and this is another thing I miss from its manual)  displaying a 50 Hz signal (conected to my1MHz circuit). The first thing I thoughtis that I made a mistake building my circuit. But then I unplugged my laptop and the diode was all green (which I understand as nothing is going to explode) and the signal it displays is less stable and around 1MHz. (Mine! and although it is not very stable i'm proud of it!!)

So, is it possible that when my computer is plugged it establishes a short cut somehow with the current entering into my house which also is 50Hz frecuency?? Which is weird becasue it means I never can work plugged.

I attached to screen shots of those to situations