Entry level oscilloscope

[boylesg]

If I was to buy a second hand oscilloscope for around $100 from ebay, can any one give me some advice on any key features/capabilities I should look out for?

 

[treez]

What are you using it for.
If just basic scoping low frequency signals then almost anything will do.
If you want to depict ringing and peak drain voltage spikes in smps's then you will need high bandwidth.
Beware some of the Far eastern ones where the save_waveform feature doesn't work on windows 8.
Do you need sample and hold....if so, don't buy analog scope.

 

[boylesg]

Anything I would be doing would be up to a frequency of a few hundred kHz.
Mucking around with audio amplifiers and audio signals.
Nothing any where as sophisticated as you guys no doubt do every day.

What exactly is the purpose of having sample and hold?

Just thinking about now I can't think of anything I would use it for.

 

[treez]

sometimes you want to examine a waveform...so you sample and hold it

Just make sure it can handle the highest voltage you will probe....the probe itself should be rated for that, but also the scope input.
How many waveforms do you wish to see at the same time.....number of channels.

Cursors are useful to measure waveform peak to peaks etc
Maplins sell cheap scopes, it it radio shack in the US?
dO YOU NEEd battery or mains......do you just want one of those scopes that is a little box and it uses your PC as the actual scope, displaying the waveforms on your computer?

 

[boylesg]

I thought about a PC oscilloscope, but than that would tie me to a PC or laptop which might be a bit of a nuisance at times, so I was considering one with a built in display.

Max voltage......can't see myself ever wanting to measure mains voltage (250V) so perhaps that would be an adequate limit. Although I suspect the voltage limit of the average oscilloscope would be a lot higher than that.

2 channels would probably enough most of the time, 4 channels would be ample.

Don't need a battery operated one - mains voltage would be adequate.

 

[tggzzz]

If you can get the educational discount, consider a Digilent Analog Discovery. The AWG and post-processing might be useful.