Oscilloscope AND amp at same time?

[Phorhas]

Hello.

I I want to both look at wave on my Oscill. and hear my amp, can I just passivly splitt the uotput, or should I use a buffing crkt?

Option 1 may introduce loading and thus alter the tone (right?) and option 2 my alter the sound as well...

So, what sould I do?

[Paul Perry (Frostwave)]

Just passively split it.
The scope probablty has an input impedance of a meg or so
(using a proper probe, not a piece of cable) so it won't notice at all.

You can always try it with & without the cro, to make sure. But I've never noticed a difference.

[Phorhas]

First of all thanx.

I'm going to use a program based oscilloscope - via the sound card, and I'll be sure to try a few approches.

[Paul Perry (Frostwave)]

If you are going to a soundcard, then a buffer might help. I don't know what the impedance of a common soundcard is, but it surely isn't anywhere near a meg! more like 10K I suspect (just guessing)..actually quick look at google indicates 10k - 30K on the line input.

[niftydog]

a good oscilloscope would be fine to connect directly to the circuit and it shouldn't affect it at all.

However, a sound card o'scope is a whole different kettle of fish. Input impedance is a complete unknown quantity, plus the maximum input voltage level could well be exceeded by connecting it to a power amplifiers output stage. You have been warned!

My advice to you is to get/build ye'self one of these interface kits (or one of these or similar) and check the maximum input voltage specs carefully before connecting it up!