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Jason Bowers Jason Bowers is offline
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Default tests to do on used oscilloscope?

On 5/3/21 6:55 PM, Phil Allison wrote:
Jason Bowers wrote:

==================

A small 1x 10x probe arrives today at last so I can at least check the
scope's square wave output signal peg. See what happens then.

The frequency still seems to be showing higher than it actually is
though. Even with a 30 Mhz scope like this, should I be able to "zoom"
in to see just one or two waveforms? So far, I can't seem to get closer
than 4-5 waveforms at 28 Mhz even with the 10x magnifier on.


** Completely normal.

28MHz is at the limit of the scope's range so no detail is visible on a sine wave.
Also, the amplitude will by down by 30% or so from that at say 5MHz.

30 MHz scopes are are not "flat" to 30MHz but will be at least 3dB down.


...... Phil


Thank you and the others here! The scope seems fine. I was finally
able to find out what happened to the square wave test peg. It
dislodged during shipping. Reattached and a nice 2V PP 1 Khz square wave.

Phil, what you said was confirmed. If I input the signal generator and
set for say 10 Mhz, the frequency and amplitude are spot on.