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Help setting Oscilloscope

gadget73 said:
seems like the scope is working since you can get a square on the screen. It remains a flat line on the generator though? What is the generator set to? Do you know for sure that the generator works?
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(emphasis added)

That makes the third time that question's been asked -- AFAIK, we're still waiting on the answer. :)

So -- @WntrMute2 -- if you hook that generator to a line level input (which seems to be what the instructions suggest) on an audio component and fire it up... do you hear the output of the generator (e.g., through loudspeakers connected to the component)?

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WntrMute2 said:
I don't know. No measurable signal on the DMV nor on the oscilloscope.
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See the additional edit to my post -- can you hear it?
So far, it's sounding like a Red Shirt on Star Trek (TOS). :(

kirk-deforest-kelley-die-hes-dead-mccoy-red-shirt-shatnerday-star-trek-william-shatner-6321185280
 
Try measuring the output of your sinewave generator with an AC voltmeter to see if you get a reading. Maybe the 'scope is working and the source is not.
 
I hooked it up to one channel of my "kit" and the tone plays loud and clear. But why can I not measure the output either via the oscilloscope on the DVM? Seems odd.
 
Nope, I measured immediately after that sound test with the same interconnect. Just unplugged it from the preamp - Voltage quickly dropped to 0.00.
 
WntrMute2 said:
I hooked it up to one channel of my "kit" and the tone plays loud and clear. But why can I not measure the output either via the oscilloscope on the DVM? Seems odd.
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You do have the DVM set to measure AC voltage, yes?
There will be (i.e., there should be) no DC voltage from the output of the generator.
 
couldn't see exactly how you were connecting things, guessing neg clip to the shell of the RCA plug, and scope probe to a wire soldered to the center pin?

Does the multimeter actually work? Is it able to read whatever frequency you have the generator set to? Many aren't good past a few hundred hz.
 
I believe the multimeter works as a second one reads the same and the clips are not shorting. I tried setting the generator to around 60hZ with no better results. So weird.
 
You know that just below the oscilloscope screen are two test points, put there for calibration, .2 volt and 2 volt square wave. You just connect the scope probe to either one,. its usually for calibrating the scope probe.
 
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I would posit that it would (should) be possible -- although it might take some finagling -- to parallel the scope probe connection to the audio connection from the generator to an amplifier. Sort of the test equipment equivalent of open heart surgery, or brain surgery on a conscious, alert patient. :)

IF one has an audio cable with an RCA plug that has a removable finger grip/insulator -- unscrew the finger grip, and use the probe (if it has micro-clips on it) or clipleads/micro-clip leads to connect the probe, in parallel, to the center conductor and shield of the "interconnect" cable where they attach to the RCA plug.

Connect the interconnect from generator to amplifier and monitor the audio as usual (sans scope connection). Presumably the tone will be audible.
NEXT, connect the scope probe in parallel. 1) do you still hear the tone via the amplifier/speakers? 2) what do you see on the scope?
I presume that the probe is cap-coupled and that the scope isn't loading down the output of the generator.

Seems to me it oughta work -- and could possibly be instructive vis-a-vis figuring out what is going on.
:cool:
 
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