Failed speaker in 396XT?

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davef3138

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I believe the speaker or audio amplifier circuit has failed in my 396XT.

The audio was sounding scratchy/distorted at volumes over 8 for about 5 minutes or so, then the speaker cut out. Plugging into the headphone jack gives me good, clean audio.

I was able to get the speaker to work twice by running the volume up and down from 0 to 15 a few times. It would sound distorted, then cut out again at any volume above 7 or so.

I did try leaving the batteries out overnight to see if that helped, it worked for a few seconds then cut out again.


Has anyone seen this before?


-Dave
 

derevs

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I would not attempt the speaker repair. The problem as you have described it sounds more like a volume control, the only descriptor you left out is "is it scratchy as you rotate the volume control". If it is, it is definitely the volume control.
 

davef3138

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Actually, the audio sounds just fine when using the headphone jack, including when operating the volume control.

The scratchiness is through the speaker, when it cuts back in, then out again.

-Dave
 

DaveeCom

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You might want to look into whether the headphone jack itself is causing a bad connection to the speaker. If you plug something in to break the connection then unplug it and see if the speaker volume gets loud, that might save having to repair it.
 

davef3138

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I tried inserting and removing a pair of headphones multiple times. It doesn't appear to be a mechanical problem with the headphone jack, as doing so doesn't cause the speaker to do anything (it's currently dead again).

Good idea though, I recall having that issue on another piece of gear - the contacts in the jack were dirty and weren't "reconnecting" the speaker.



-Dave
 

Bullmax

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I just encountered the exact problem today. The speaker started sounding scratchy and all of a sudden no more sound. Scanner is only 2 months old.
 

davef3138

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Update: I ended up sending it in for warranty repair (I had a few months left on the original warranty).

It came back about 3 weeks later; the sheet from the repair facility simply said "speaker" where the work done was listed. It's back to normal now.
 

gvranchosbill

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Re:uniden br-330-t speaker failure

RE:SPEAKER FAILED TODAY WHILE MONITORING NEVADA-ENERGY POWER CO DURING
MAJOR POWER OUTAGES DURING 70MPH WINDS(STORM MOVING IN) SOUND HAS BEEN
VERY GOOD FOR THE PAST YEAR 1/12,NOT SCRATCHY OR WEAK INFACT SOUND QUALITY
TODAY WAS FULL AND BOOMING, HAD BEEN ON FOR ABOUT 8HRS WITH CONTINUED
TRANSMISSIONS WITH NOT MUCH OF A BREAK (BUSY) THEN ALL OF A SUDDEN SOUND
SOUNDED LIKE OFF FREQUENCY/BLEEDOVER BUT WAS NOT THE CASE QUALITY RAPIDLY
DECLINED THEN WAS NO MORE,NOT A BEEP OR ANY SOUND EMMITING FROM SPEAKER.
I PLUGGED IN A EXTERNAL SPEAKER AND SOUNDED GREAT, PLUGGED THE PLUG IN AND
OUT SEVERAL TIMES WITH NO EFFECT, JACK DOES NOT FEEL OUT OF WACK, MY OPINION
IS THAT WITH MY CONTINUED USE WITH VOLUME @ ABOUT 2/3rds UP THAT IT FAILED
HAS THIS BEEN COMMON? I READ A FEW THREADS REGARDING OTHER UNIDEN SCANNERS
EXAMPLE (BC396T) (ALMOST IDENT TO BR330T) WITH THE SAME PROBLEM, UNIDEN REPLACMENTS ARE BACK ORDERED IS THERE ANOTHER PLACE TO LOCATE REPLACMENT?
ALSO THER IS NO ABNORMAL FEEL IN THE VOLUME CONTROL,NO SKIPPING OR SCRATCHY
SOUNDS.
 
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KE4ZNR

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RE:SPEAKER FAILED TODAY WHILE MONITORING NEVADA-ENERGY POWER CO DURING
MAJOR POWER OUTAGES DURING 70MPH WINDS(STORM MOVING IN) SOUND HAS BEEN
VERY GOOD FOR THE PAST YEAR 1/12,NOT SCRATCHY OR WEAK INFACT SOUND QUALITY
TODAY WAS FULL AND BOOMING, HAD BEEN ON FOR ABOUT 8HRS WITH CONTINUED
TRANSMISSIONS WITH NOT MUCH OF A BREAK (BUSY) THEN ALL OF A SUDDEN SOUND
SOUNDED LIKE OFF FREQUENCY/BLEEDOVER BUT WAS NOT THE CASE QUALITY RAPIDLY
DECLINED THEN WAS NO MORE,NOT A BEEP OR ANY SOUND EMMITING FROM SPEAKER.
I PLUGGED IN A EXTERNAL SPEAKER AND SOUNDED GREAT, PLUGGED THE PLUG IN AND
OUT SEVERAL TIMES WITH NO EFFECT, JACK DOES NOT FEEL OUT OF WACK, MY OPINION
IS THAT WITH MY CONTINUED USE WITH VOLUME @ ABOUT 2/3rds UP THAT IT FAILED
HAS THIS BEEN COMMON? I READ A FEW THREADS REGARDING OTHER UNIDEN SCANNERS
EXAMPLE (BC396T) (ALMOST IDENT TO BR330T) WITH THE SAME PROBLEM, UNIDEN REPLACMENTS ARE BACK ORDERED IS THERE ANOTHER PLACE TO LOCATE REPLACMENT?
ALSO THER IS NO ABNORMAL FEEL IN THE VOLUME CONTROL,NO SKIPPING OR SCRATCHY
SOUNDS.


It is difficult to try to read your post in all caps.
Marshall KE4ZNR
 

jbeez

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Update: I ended up sending it in for warranty repair (I had a few months left on the original warranty).

It came back about 3 weeks later; the sheet from the repair facility simply said "speaker" where the work done was listed. It's back to normal now.
I got my 396xt back tuesday from repair, 3 weeks at uniden, repair paperwork just said speaker as well.

I sent mine in the last week of its original warranty, luckily they also have a repair warranty that covers it for a bit of time after, I forget 1 or 3 months from date of repair.

Speaking of which, I'd like to not use the internal speaker at all anymore. I've been looking with no luck, I'd like something exactly like this, but headphone jack instead of USB,
Amazon.com: Laptop Speakers - USB, Portable, Compact, Travel Speaker for PC and Mac - B-Flex 2 Hi-Fi Stereo USB Speaker (White): Electronics

So I can just keep it plugged in and use that instead of the internal speaker and not worry about messing up the scanner.

My internal speaker was bad enough that I couldn't even use the scanner with headphones, it must have been shorting or something.
 

jackj

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According to Uniden's manual on the 396XT, the audio output is 310 mW across a 24 ohm load. While the speaker is rated at 0.8 W, 24 ohm. So the unit's max output is 0.31 watts while the speaker should be able to handle 0.8 watts.

From what you have described, the problem you are having is that the speaker's voice coil is getting cocked or distorted and dragging on the magnet. When this happens, the only fix is to replace the speaker with one that is a little better built. Buying the replacement from Uniden will get you the OEM version which is what failed. I would recommend finding a supplier that could sell you the same size speaker rated at 1 or 1.5 watts.
 

jbeez

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I don't have a ton of working experience with speakers this small, but when you have larger house speakers underdriving them can be pretty bad, you can distort the incoming audio signal to the speaker and cause damage. I'm of the opinion of supplying enough clean power to not cause distortion and risk thermal failure of the driver rather than feed it a nasty audio signal with distortion in it. Because I have my volume at 100% just to hear it, that's more than the amp can provide cleanly. It's tough to balance this on a scanner because the source volumes vary so greatly with different people talking and different systems, etc. even with AGC.

I was just doing some research after I posted this and found a great article explaining what I was trying to explain but with proper terms and theory behind it, http://www.audiojunkies.com/blog/13...distortion-clipping-and-everything-in-between
 
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jackj

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Power

I don't have a ton of working experience with speakers this small, but when you have larger house speakers underdriving them can be pretty bad, you can distort the incoming audio signal to the speaker and cause damage. I'm of the opinion of supplying enough clean power to not cause distortion and risk thermal failure of the driver rather than feed it a nasty audio signal with distortion in it. Because I have my volume at 100% just to hear it, that's more than the amp can provide cleanly. It's tough to balance this on a scanner because the source volumes vary so greatly with different people talking and different systems, etc. even with AGC./QUOTE]

It is impossible to damage a speaker by "underpowering" it. Likewise, reducing the power supplied to a speaker will not cause more distortion. Someone has been giving you bad information. I recommended replacing his OEM (Original Equipment Manufacturer) speaker with one that would handle more power because it sounds to me like the OEM speaker has been damaged by high volume levels. Good engineering practice is to spec a speaker that can handle twice as much power as the amp's rating. It looks, from the radio's specs, that Uniden did just that. But I think the speaker they are using isn't really as hefty as the specs show.
 

gonorth

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396 Speaker Replacement

The speaker in my 396xt failed several months ago. I had accidentally left the radio on in my car overnight on high volume. I figure a couple tone-outs killed it. I found this article very handy,

Replace a Blown Speaker in the 396 - The RadioReference Wiki

I just purchased the OEM speaker directly from Uniden. It was relatively easy and inexpensive. I don't set the volume above 12 now, I was using it full tilt.



Of course at the moment the speaker shows as backordered.

Jon -- N1QGL
 

jackj

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No radio should be able to destroy it's OEM speaker even when played overnight at maximum volume
Gonorth. If it can then the manufacturer is guilty of poor engineering or poor bean-counting. Neither of which speaks well of the manufacturer.
 
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