need help using a DMM

[norcalSRTrida 10+ year member]

http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&category%5Fname=CTLG%5F011%5F008%5F002%5F000&product%5Fid=22%2D813

ran to radioshack and picked a simple one up to set my gains.

do i need to use AC or DC?

and when i was trying to set it using AC...everytime i turned the level up on my amp the voltage would go down, and when i turn down the level the voltage went up?...

DC mode...it wouldnt even read any # close to being realistic.

help me out.

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[SSS 18734 5,000+ posts]

i assume your trying to set your gains...

Connect the wires to the speaker outputs, with HU volume up around 3/4 with the desired test tone. Turn it to AC voltage 50 and set the gains from there. If you have over 50 volts, turn it to the next highest setting...

 

[norcalSRTrida 10+ year member]

i assume your trying to set your gains...
Connect the wires to the speaker outputs, with HU volume up around 3/4 with the desired test tone. Turn it to AC voltage 50 and set the gains from there. If you have over 50 volts, turn it to the next highest setting...

i disconnected my wires from the speaker outputs and inserted the prong thingys from the DMM.

i had my volume set at the desired level and played a repeated 50hz sine wave.

i dont understand the AC voltage 50? i set it to the AC setting and everytime i turn up the gain, voltage goes down and vice versa...i cant put my finger on why its doing that.

 

[joeboxer5876 10+ year member]

thats exactly what its supposed to do. "turning up the gain" as you say, is just setting the input voltage higher. when you set the input voltage all the way up to 8 volts when you HU is only 4 volts, then then volts (power to your speakers) will drop.

 

[norcalSRTrida 10+ year member]

thats exactly what its supposed to do. "turning up the gain" as you say, is just setting the input voltage higher. when you set the input voltage all the way up to 8 volts when you HU is only 4 volts, then then volts (power to your speakers) will drop.

that explains it. thanks for the insight.