Oscilloscope advice.

[Chris1234]

Morning, I’m looking to buy a cheap portable oscilloscope. Or a unit that connects to my iPhone.
I’ve heard the cheap ones on eBay are ok.
I just need it to monitor the output from a rotary encoder, it gives a square wave output that varies in frequency according to rotation speed.

Do you know if the cheap ones record data or just show a waveform?
Does they record times of events/alerts?
Can you set them to alert you to a audience change in frequency or noise?

Thanks

 

[Harald Kapp]

Do you know if the cheap ones record data or just show a waveform?

That should be stated in the scope's specs.

Does they record times of events/alerts?

If it records, it records time, too, that's the job of a scope.

Can you set them to alert you to a audience change in frequency or noise?

Normally not.

Tell us what you want to achieve with these functions. An oscilloscope may not be the best suited tool here.

 

[Michael Studio1]

Morning, I’m looking to buy a cheap portable oscilloscope. Or a unit that connects to my iPhone.
I’ve heard the cheap ones on eBay are ok.
I just need it to monitor the output from a rotary encoder, it gives a square wave output that varies in frequency according to rotation speed.

Do you know if the cheap ones record data or just show a waveform?
Does they record times of events/alerts?
Can you set them to alert you to a audience change in frequency or noise?

Thanks

I recently purchased a 'Pocket-size, Open source, 200KHz bandwidth, 1Ms/s sample rate, 8M storage built in, Black Aluminium Alloy case. Just for messing around with. It's a DS201 PRO Oscilloscope with CD-ROM & Probe. Less than $100. It's tiny (as the Pocket-size suggests) with small USB (not micro though, output) and has a 2 7/8" diag. screen. Colour - of course! Look it up - and the specs and op. instructions are online. Michael Studio1 UK

 

[globecollector]

One really cheap way to monitor the output of a rotary encoder would be to pad the output of the encoder down and feed it into an audio amplifier (and just listen to the tone produced). if it is above the audible range a "T" Flip flop would divide it by two.....or use sound card of a PC running software like "Audacity" that will give not anly the waveform and frequency but record events too.

 

[Michael Studio1]

One really cheap way to monitor the output of a rotary encoder would be to pad the output of the encoder down and feed it into an audio amplifier (and just listen to the tone produced). if it is above the audible range a "T" Flip flop would divide it by two.....or use sound card of a PC running software like "Audacity" that will give not anly the waveform and frequency but record events too.

Than you, Globecollector, our Studio PC has Audacity and several Steinberg programmes, of course, so we can give this a trial! Michael Studio1 UK 06:17BST 05-07-2018

 

[Engineer_Paul]

Morning, I’m looking to buy a cheap portable oscilloscope. Or a unit that connects to my iPhone.
I’ve heard the cheap ones on eBay are ok.
I just need it to monitor the output from a rotary encoder, it gives a square wave output that varies in frequency according to rotation speed.

Do you know if the cheap ones record data or just show a waveform?
Does they record times of events/alerts?
Can you set them to alert you to a audience change in frequency or noise?

Thanks

Morning, I’m looking to buy a cheap portable oscilloscope. Or a unit that connects to my iPhone.
I’ve heard the cheap ones on eBay are ok.
I just need it to monitor the output from a rotary encoder, it gives a square wave output that varies in frequency according to rotation speed.

Do you know if the cheap ones record data or just show a waveform?
Does they record times of events/alerts?
Can you set them to alert you to a audience change in frequency or noise?

Thanks

 

[Engineer_Paul]

For an encoder you will need at least two input channels, as there are usually 3 outputs but the A and B are the ones that are most often used. Not so important that it have memory, but that is the only way that you will be able to see the signals in real time. Also look at 10 mhz bandwidth minimum, preferably more, as encoders show one signal before the other depending on what direction that it is rotating. This is called quadrature output. Also keep in mind that there are different kinds of output from encoders, and what you need to know is if you are going to need to add pull up or pull down resistors as well.