oscilloscope help

[photocrazy8 10+ year member]

I want to set my gains with and oscilloscope because with a DMM its not as loud as i know it can go. So what is a good brand of oscilloscope that is fair priced. And when it says bandwith is it refering to how low and high of Hz's it can measure? Because most people say to set the gains with a 50 Hz wave so do most oscilloscopes measure that low? Thanks, Andrew

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[GemaRastem 10+ year member]

oscilloscope and cheap don't go together //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif. I have one that is about 7 years old, crappy green screen, goes for $800 on ebay.

 

[SubbinNCali 10+ year member]

WOW! Thats kinda nice to know. A pawn shop near me has one for $125.

 

[jimmyjames1700 10+ year member]

I want to set my gains with and oscilloscope because with a DMM its not as loud as i know it can go. So what is a good brand of oscilloscope that is fair priced. And when it says bandwith is it refering to how low and high of Hz's it can measure? Because most people say to set the gains with a 50 Hz wave so do most oscilloscopes measure that low? Thanks, Andrew

Honestly, it's not going to get any louder buy using a scope to set your gains. In fact, you may find that your gains were too high in the first place by calculating and using a mulitmeter. When you calculate your target voltage and use a DMM to set your gain to that voltage level, you're disregarding any clipping or distortion which would most likely be shown by the scope.

What I am trying to get at here is the fact that you will probably see distortion at a much lower voltage using an O'scope than just arbitrarily setting your gains with calculation/multimeter method.

Save your money and just do it the way it was done for years, use your ears. Besides, I don't know that you could find a decent scope for less than $1,000, at least not a HP or Tektronix or even a Fluke

But if you still want some more info about O'scopes, I would be glad to help out.

 

[DBfan187 5,000+ posts]

http://www.carsound.com/forum/showthread.php?t=9416

here for scope - http://cgi.ebay.com/VELLEMAN-HPS10SE-HPS10-SE-SPECIAL-EDITION-SCOPE_W0QQitemZ7613172401QQcategoryZ104247QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

 

[GemaRastem 10+ year member]

hmmm, that actually looks like a semi decent scope, didn't know you could find em that cheap. although it is analog but that's not a big deal for caraudio

 

[nauc 10+ year member]

i got this

$125 new http://www.elexp.com/tst_hhs5.htm

works just fine, easy as hell to use

he threw in a free dmm too!!!

 

[thch 10+ year member]

although it is analog but that's not a big deal for caraudio

2Mhz analog bandwidth. the oscope measures analog signal after all. its a digital based design, 10M samples/second.

not that you can equate digital with quality. 6bit resolution on the screen limits its uses a bit.

 

[photocrazy8 10+ year member]

well i have had problems with a bad volatge drop and i have has some people tell me that it could be the settings of my gain that would cause the voltage drop. and there have been so many way/setting for the HU and the amp its hard to get a correct way to set the gain. so im still a little lost

 

[nauc 10+ year member]

well i have had problems with a bad volatge drop and i have has some people tell me that it could be the settings of my gain that would cause the voltage drop. and there have been so many way/setting for the HU and the amp its hard to get a correct way to set the gain. so im still a little lost

im no expert but, your setup seems too much for what you have, all those batteries and such, and the 1000/1 is kinda small for the XXX

just my first thoughts....

 

[photocrazy8 10+ year member]

im no expert but, your setup seems too much for what you have, all those batteries and such, and the 1000/1 is kinda small for the XXX
just my first thoughts....

yea i know, but i can drop the volatge to about low 12's, maybe high 11's. i went to a car audio shop and they said the 1000/1 is drawing about 180 amps. so some where i have a weak link in my electrical system.

 

[nauc 10+ year member]

yea i know, but i can drop the volatge to about low 12's, maybe high 11's. i went to a car audio shop and they said the 1000/1 is drawing about 180 amps. so some where i have a weak link in my electrical system.

i pmed you...

 

[helotaxi 5,000+ posts]

I still don't get why people set their gains using a multimetre, or cro...
the point of setting the gains, is so the fronts, and sub match each other...

set the headunit volume at like 2/3rds full volume, set the fronts to a loud listening level, then adjust the sub to match....

makes sense to me...

The point of setting the gains is to get power from the amp without clipping. System balance is usually best done by setting the gains on all amp independantly and then adjusting down the gain on whichever amp is too loud to achieve good balance. Most HUs have a sub level adjustment nowadays anyway. Set the gain for max unclipped power and then dial it down to match the front stage with the sub level control. Leaves you the ability to bump it when you want and dial it down when you don't need that much bass.

 

[nauc 10+ year member]

but that completely depends on the input signal to the amp.... //content.invisioncic.com/y282845/emoticons/eyebrow.gif.fe2c18d8720fe8c7eaed347b21ea05a5.gif
you cant set the amp for the maximum, unclipped output, unless all you're playing is sinewaves, which you're not...

so, its completely pointless.

no, but you use non-attenuated test tones, around 40hz for subs, 1k for highs, with flat eq settings so when you play music, theres no clipping

 

[nauc 10+ year member]

but whats it actually prove?
that your amps aren't clipping when you're playing a 0dB sinewave?

yeah, thats... ah, great

if set with a scope, yes