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Don’t know what I’m doing Amp project. Help!!

Viking70806

Feb 15, 2021
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Hello electric ladies and gentlemen. I am an aspiring electronic wiz with little knowledge and need some input. In short I am mounting a small practice guitar amp in a small suitcase. I’m also adding some effect pedals to it. I want one plug to power both the amp and 9v pedals. So....

I noticed the big transformer thing in the amp said 120v input 60Hz to 12v 0.5A output

so I assumed it was stepped down from 120 wall voltage to 12v to power the amp. I ordered a 12v to 9v little step down module on Amazon and was about to wire it in. I checked the output leads from the transformer and is reading 13.37ish volts not 12...

when I hook up step down module I get readings all over the place

I feel like I should know what I’m doing to further the project. Anyone have any thoughts?
 

Harald Kapp

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Nov 17, 2011
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  1. 13.37 V as the output of a nominal 12 V transformer is o.k. The output voltage will drop if the amp is active and draws power from the transformer.
  2. You cannot connect a step down module directly to the output of a transformer. Well, you can as you obviously did, but that makes no sense at all. A transformer has an AC output, the module requires DC. You'll have to find a point within the amplifier's power supply where you can tap into a DC voltage.
 

AnalogKid

Jun 10, 2015
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Anyone have any thoughts?
Anyone have any links to product pages? Or photos? Anything with writing on it. any connectors.

What are you using to measure voltages? If it is a meter, is it on an AC or Dc scale? It's kinda important.

"Big transformer thing" is a relatively useless description. If if is an open-frame transformer, the output almost certainly is 12 V ***AC*** and will not drive a DC/DC converter correctly. If it is in an enclosure or package, like a plastic box with a label on it, if might have a DC output. But then, why is it running over 10% hot? Only you have the information to answer these questions.

"Big transformer thing" is a relatively useless description. If you're gonna be a wiz, ya gotta to talk like one. I get that you're new to all of this, but "Big transformer thing"? Really?

ak
 

Viking70806

Feb 15, 2021
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Lol. Thank you very much for your reply.(and not taking the opportunity to laugh at my ignorance). I need to crack the books on some simple electronic circuits and logic. Any recommendations?
 

Viking70806

Feb 15, 2021
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Feb 15, 2021
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Anyone have any links to product pages? Or photos? Anything with writing on it. any connectors.

What are you using to measure voltages? If it is a meter, is it on an AC or Dc scale? It's kinda important.

"Big transformer thing" is a relatively useless description. If if is an open-frame transformer, the output almost certainly is 12 V ***AC*** and will not drive a DC/DC converter correctly. If it is in an enclosure or package, like a plastic box with a label on it, if might have a DC output. But then, why is it running over 10% hot? Only you have the information to answer these questions.

"Big transformer thing" is a relatively useless description. If you're gonna be a wiz, ya gotta to talk like one. I get that you're new to all of this, but "Big transformer thing"? Really?

ak
I’m sorry but for some reason my pictures I took won’t upload. I’m using a klein mm400 multimeter
 

davenn

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Sep 5, 2009
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I’m sorry but for some reason my pictures I took won’t upload. I’m using a klein mm400 multimeter


Hi and welcome
Resize them to a max of 800 x 600 pixels and with a kb size of ~ 100kb ... Dont try and upload multi-Mbyte sized files
 
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