how to use oscilloscope

[robertccy]

Hi, i like to buy a DSO nano oscilloscope for my tube amp project. i only know how to use a digital multimeter but never use a digital scope meter before. Recently i noticed that something wrong with my diy tube power amp but no where to check with my digital multimeter, look like with terrible distortion. i heard that with a oscilloscope i can check what is going on with the signal in side my amp.
ok. now i like to know whether i can put in a signal taken out from the generator which is build in DSO NANO to my amp input. and switch on the amp with connect a speaker or 8 ohm resistor at the speaker terminal.and measure every part in side the amp to see whether the sine wave is the same with the generator? or.....
Thank you

[AndrewT]

you could try googling oscilloscope.
There are a few, maybe many, instructions on how to use and interpret what you see.
There are some threads here that explain what is needed and how to use/interpret.
I think ESP also has a bit.
There are also small text books that tell you how to use various test instruments. I have a variety by Babani (various authors) and others.

[robertccy]

Originally Posted by AndrewT

you could try googling oscilloscope.
There are a few, maybe many, instructions on how to use and interpret what you see.
There are some threads here that explain what is needed and how to use/interpret.
I think ESP also has a bit.
There are also small text books that tell you how to use various test instruments. I have a variety by Babani (various authors) and others.

Thanks Andrew,
I did tried in google but cannot get what i want. I am a beginner but i know tube amp with a few hundred volt and not the same with transistor. So, anyone can show me a link or any where for instruction to use the scope？

[xmas111]

if you have the time this is a pretty good video.

Oscilloscope School

John

[wakibaki]

Originally Posted by robertccy

i like to know whether i can put in a signal taken out from the generator which is build in DSO NANO to my amp input. and switch on the amp with connect a speaker or 8 ohm resistor at the speaker terminal.and measure every part in side the amp to see whether the sine wave is the same with the generator?

Yes, you've got the idea. You can also try square wave, will tell you some other things, but first, try sine.

Originally Posted by robertccy

tube amp with a few hundred volt

Yes, you must connect the ground lead on the scope probe to ground on the amp. Big voltages will destroy some scopes, particularly PC scopes, so check the scope manual and check the amp with DMM first if you don't know the voltage.

Be careful, tube voltages can kill you. Old advice is to keep one hand in your pocket to avoid a shock across the heart.

w

[robertccy]

Originally Posted by wakibaki

Yes, you've got the idea. You can also try square wave, will tell you some other things, but first, try sine.



Yes, you must connect the ground lead on the scope probe to ground on the amp. Big voltages will destroy some scopes, particularly PC scopes, so check the scope manual and check the amp with DMM first if you don't know the voltage.

Be careful, tube voltages can kill you. Old advice is to keep one hand in your pocket to avoid a shock across the heart.

w

Thanks,
you are scaring me . The B+ voltage in my amp is 420vdc. so can i use the pocket digital scope (Nano DSO scope meter) to do that?
Thanks again

[aardvarkash10]

hard to know, but I would be wary of anything that asked me to hold a probe on it at that voltage....

[wakibaki]

Is it this one? Buy Oscilloscope dso 1200, portable Oscilloscope, handheld Oscilloscope, USB HandHeld Scopemeter Oscilloscope DMM 5.7" DSO1200+2yrs Warranty at Aliexpress.com

Maximum voltage on this one is 400V.

You can use a voltage divider, but if you are a beginner ...I think you are...

Originally Posted by robertccy

i only know how to use a digital multimeter but never use a digital scope meter before.

... better to start electronics with solid state (transistors). Lower voltage, less risk to both you and scope. If you have a problem with this amp and you need to get it fixed, take it to an experienced person, even if you have to pay.

w

[TheGimp]

HP has some nice tutorials on Oscilloscope usage as does Tektronix.

Gopher Google.

Oscilloscope Tutorial | Tektronix

[robertccy]

Originally Posted by wakibaki

Is it this one? Buy Oscilloscope dso 1200, portable Oscilloscope, handheld Oscilloscope, USB HandHeld Scopemeter Oscilloscope DMM 5.7" DSO1200+2yrs Warranty at Aliexpress.com

Maximum voltage on this one is 400V.

You can use a voltage divider, but if you are a beginner ...I think you are...



... better to start electronics with solid state (transistors). Lower voltage, less risk to both you and scope. If you have a problem with this amp and you need to get it fixed, take it to an experienced person, even if you have to pay.

w

So, what brand of scope i should buy for my tube power amp? Thanks