repairing a tiny powered speaker

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Rich4349
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Joined: Wed Jul 30, 2008 10:18 am
Location: Kankakee, IL

repairing a tiny powered speaker

#1 Post by Rich4349 »

I'm checking out a small powered police radio monitor for a friend. It has line in leads, as well as AC in wires.

1 How do I tell how many volts or amps this thing requires?

2 What I'm guessing are the power transformers have a decent amount of rust on them. How do I tell if they are good or bad?

I ran signal alone via the 1/8" out jack on my phone to the line in, and there was just barely very crackly audio. Is it normal to sound terrible with no amplification? The driver APPEARED to be intact.

Here's the pic https://www.dropbox.com/s/sud87xk5ryz4n ... 6.jpg?dl=0
2 DR250s, 2 27" Lab15 T-60s, 2 30" Neo Titan 39s, 1 Autotuba...and looking for more!

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Bill Fitzmaurice
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Re: repairing a tiny powered speaker

#2 Post by Bill Fitzmaurice »

Unless you're highly experienced it's almost impossible to work on something without a schematic.

Grant Bunter
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Re: repairing a tiny powered speaker

#3 Post by Grant Bunter »

Rich4349 wrote:I'm checking out a small powered police radio monitor for a friend. It has line in leads, as well as AC in wires.

1 How do I tell how many volts or amps this thing requires?

2 What I'm guessing are the power transformers have a decent amount of rust on them. How do I tell if they are good or bad?

I ran signal alone via the 1/8" out jack on my phone to the line in, and there was just barely very crackly audio. Is it normal to sound terrible with no amplification? The driver APPEARED to be intact.

Here's the pic https://www.dropbox.com/s/sud87xk5ryz4n ... 6.jpg?dl=0
+1 to Bill's post.

Somewhere on the chassis or the outer covering will be a brand name and a model number.

Google the name and the model number and add schematic in the search.
It is best to presume at this stage you're dealing with mains power, so it is dangerous, potentially lethal.
Having said that, DON"T APPLY MAINS POWER TO IT until you know what your dealing with via aforementioned schematic. You could cause further damage if it isn't mains powered.

Get back to us with name and model as well.
It is "normal" for an item such as this to sound crackly and have no amplification when it has faults...
Built:
DR 250: x 2 melded array, 2x CD horn, March 2012 plans.
T39's: 4 x 20" KL3010LF , 2 x 28" 3012LF.
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