I need some help tuning my amps with a oscilloscope

[Snuskgamer]

I have an fluke 43B power quality analyser.
And I'm having trouble with reading the rca voltage, I'm getting a output of 0.2 volts and my head unit is supposed to have a rca voltage of 2 volts.

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[Jimi77 5,000+ posts]

.2 volts at full volume?

 

[Snuskgamer]

.2 volts at full volume?

Yeah or maybe 0.4 i did not have it on full volume for that long

 

[Jimi77 5,000+ posts]

Are you using music or a sine wave? A sine wave should produce the proper voltage reading. Try using a DMM set to AC instead of the oscope.

 

[metalheadjoe 10+ year member]

@Snuskgamer did you mistakenly set your probes to x10. Try a different frequency or turn off your low pass filter.

@Jimi77 i disagree. An oscilloscope is a much more accurate tool if you know how to use it.

 

[Snuskgamer]

Are you using music or a sine wave? A sine wave should produce the proper voltage reading. Try using a DMM set to AC instead of the oscope.

Im using a sine wave

 

[Snuskgamer]

@Snuskgamer did you mistakenly set your probes to x10. Try a different frequency or turn off your low pass filter.

@Jimi77 i disagree. An oscilloscope is a much more accurate tool if you know how to use it.

Im quite sure that I'm not using 10x but I don't really know, I only borrowed the oscilloscope from a friend.

 

[metalheadjoe 10+ year member]

Im quite sure that I'm not using 10x but I don't really know, I only borrowed the oscilloscope from a friend.

If you see exactly 1/10 of what you expect to see, it's worth checking. See my attached picture. There is a slider switch on every probe I've used.

 

[Snuskgamer]

If you see exactly 1/10 of what you expect to see, it's worth checking. See my attached picture. There is a slider switch on every probe I've used.View attachment 49353

I dont have that slider but I got this menu and I think that it is the same

 

[metalheadjoe 10+ year member]

I dont have that slider but I got this menu and I think that it is the same

I've never used a digital scope, so I don't know what those settings should be. Are you confident that all settings are correct? Should we suspect scope settings or rule that out?

Edit: i have never used a power analyzer, but I suspect it gives different info than an oscilloscope, and that's why your reading is off. Connect it to a known voltage such as your battery or 120 outlet if it can read that high.

 

[Snuskgamer]

I've never used a digital scope, so I don't know what those settings should be. Are you confident that all settings are correct? Should we suspect scope settings or rule that out?

Edit: i have never used a power analyzer, but I suspect it gives different info than an oscilloscope, and that's why your reading is off. Connect it to a known voltage such as your battery or 120 outlet if it can read that high.

I connected it to the battery and I was 12 volts as it should. But I had it set for DC to check the battery and AC to check the rca cable

 

[Jimi77 5,000+ posts]

Are you having some sort of issue with the signal - ie amp isn't getting as loud as expected? Sometimes things just don't read properly. I just spend the afternoon troubleshooting my sprinkler system. 24vdc AC/DC converter read 1.3vdc. The trigger lines to the sprinkler valves should have read 24vdc too, but came in at 800mvdc. Same DMM read 120vac out of the outlet, read 24vdc off another ac/dc converter, read 3vdc on a remote control. The sprinkler system is still working even though it allegedly only has ~1vdc.

 

[Snuskgamer]

Are you having some sort of issue with the signal - ie amp isn't getting as loud as expected? Sometimes things just don't read properly. I just spend the afternoon troubleshooting my sprinkler system. 24vdc AC/DC converter read 1.3vdc. The trigger lines to the sprinkler valves should have read 24vdc too, but came in at 800mvdc. Same DMM read 120vac out of the outlet, read 24vdc off another ac/dc converter, read 3vdc on a remote control. The sprinkler system is still working even though it allegedly only has ~1vdc.

The rca is suppose to have ~2 vac before clipping but my HU is only producing 0.2 vac clean before clipping.

Edit: there is coming sound out of the sub and speakers I just want to know how much I can tune it before it's clipping

 

[dragon.breath 10+ year member]

What db is the test tone that you are using? The wrong test tone could cause the results that you are getting.

 

[Snuskgamer]

What db is the test tone that you are using? The wrong test tone could cause the results that you are getting.

0 Db i think