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Ralph Mowery[_3_] Ralph Mowery[_3_] is offline
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Default tests to do on used oscilloscope?

In article ,
says...

my signal generator outputs some wonky voltages unless you have a load
resistor across the outputs. It's 600ohms in a box with 1" spacing banana
plugs and receptacles. I could never figure out why that's not handled by
a pushbotton.

Also, make sure you don't have any knobs pulled out putting you in zoom
mode. My signal generator has one of silly scope knobs too for some
reason.



Signal generators are designed to put out a certain voltage into a
certain load. Think of them as having a signal generating source of
zero impedance in series with a resistor. Any load will devide between
the internal impedance and the load impedance.

For RF generators there were two standards. One was an open circuit Or
very high impedance) voltage and the other was for a 50 ohm load. My
service monitor has a software setting to do either one. It is from the
old analog cell phone days and 30 years ago the cost was about $ 50,000.
When the cell phones went digital the service monitor was put out for
surplus and are selling for under $ 1000 now on the used market.

When using a scope you have to allow for the peak or peak to peak ratio
to the RMS value of a sine wave. As mentioned before I don't recall the
ratio as I seldom need it and the scope I have now will calculate it and
put on the display. If your RMS meter shows abot 120 volts AC out of
the wall socket a scope will show around 170 volts peak.