how to use oscilloscope

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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.....:scratch: :cheeky:
Thank you
 
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.
 
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?
 
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.

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
 
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
 
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...

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
 
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
 
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IF your scope is the dso 1200 the specifications and functions look very nice and it should fit your needs for general purpose trouble shooting.

1st thing to learn about electronic test equipment - READ THE MANUAL!!!
If the manual doesn't cover information that you need to know then get in contact with a friend that is knowledgeable about electronic test equipment and trouble shooting to show you the ropes. You might find someone here - or some other threads such as PE tech talk - that is in your area and willing to help out.

The high voltages present in vacuum tube circuits will not cut you any slack because you are a "beginner". In fact those little electrons are always very sneaky and looking for the quickest way to return to ground - and if you make yourself (or your test equipment - test leads - etc.) the easiest path you (or the gear) are gonna take a hit. That should concern you - if it doesn't concern you now lemme know so I can take out an insurance policy on you - I can use the money. :eek:

Sorry - I hate to be a hardassssss - but like a crusty old Drill Instructor that actually cares a lot about you and your future - I have to drill this one point into your head. BE SAFE!!!!

You need a voltage probe that will exceed (by a good margin - usually 50%) your highest measurement requirements - in this case 420VDC. Take a look at these - Note: I haven't used these and I don't vouch for them - this is merely intended as an example of HV probes on the market. Two 250MHZ Oscilloscope clip probes 100X up to 1.2KV | eBay

My experience to back up these statements - 40 plus years repairing electronic gear and a couple of those years were worked in a precision calibration lab as a cal and repair technician. ;)

Also take a look here: http://basic-electronics.blogspot.com/2008/08/html-clipboard-safety-precautions.html
 
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So, what brand of scope i should buy for my tube power amp? Thanks

You can try and get a nice older Tektronix off ebay. I got a model 465 that way. It is high bandwidth, very nice machine, and bulky. I also got a 100x probe (100 times attenuation) to allow me to work with higher voltages in tube amps, up to 750volts.

I don't know, after you work with the real thing, cheap digital ones don't feel the same at all...
 
I have just taken the same journey and decided against the mini scope, and also decided against the big old Tektronix sitting on my bench. Instead I have started using the Virtins computer scope. This one uses a sound card as input and output.

I am using a Beringer UCA202 USB external sound adapter BEHRINGER: UCA202 These sell for about $30 USD or less and actually sound pretty darn good. and they have 2 RCA jacks in and out.

I use this with virtins softward and a virtins probe ($35.00) Virtins Technology: Turn a PC into Virtual Instrument - Home

For $50 usd you get a scope, signal generator, etc..... check out the website lots of great information. I also love their documentation......very detailed information on all functions. You can also download a 27 day demo version before you pay for it.

I am not a newbe....but maybe a midbe. So far I am having a great time testing with this and have only bought the probe. I had the Behringer around anyway.

Actually have bee using the Behringer with Fubar 2000 as a music server with my laptop.
 
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