Radio Interference

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Crane
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Posts: 350
Joined: Sat Dec 23, 2017 5:44 am

Radio Interference

Post by Crane »

Wondering if anyone else has dealt with this.

I have an 808 that you can lightly hear a radio station through the headphones, and playing pads through the headphones is very loud and distorted. The main outputs work and sound normal.

It is definitely a fault on the main board that houses the in's/out's as I swapped the boards between two units and the "radio" followed to the second 808.

My assumption is that the chip (pictured below) is a preamp as there is one on every in/out socket and that is what is causing the issue.

Just wondering if anyone has any other insight on what is causing this, or if I can just buy any 8 pin preamp chip and replace it.

Thanks
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Crane
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Re: Radio Interference

Post by Crane »

Just a follow up for future searchers.

The 4570 preamp chip can be bought for 10 for a dollar from China, but it did not fix the problem.

The fault seems to be with the capacitors and diodes pictured below. R-97, R-98, C-67, C-66.

Testing is complete on my behalf as the 808 was sold, but if anyone else has the same problem this is where to start.
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drmnaga78
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Location: Bristol, UK

Re: Radio Interference

Post by drmnaga78 »

Thanks for the info'
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