amplifier

Denon AVR-1801 – Blinking Red Light Repair

IMG_20150820_103928The other day, my Denon AVR-1801 home theater receiver stopped working. It would power on, reach the point where it normally enabled the speaker outputs, but then it would shut off. The status LED would rapidly blink on and off.

The user manual suggested that the device was overheating, or that the speaker terminals were being shorted. The device was not hot, as it was just turned on. I unplugged all input and output cables, but that didn’t fix it either. Time to dig deeper.

 

The Problem

A quick Google search revealed the following gem. There are four “surge” resistors in line with the ┬▒15 VDC regulators: R141, 142, 148, 149. These 1 Ohm resistors weaken over time with every power-on surge, and the resistors from the factory were not strong enough. Armed with this knowledge, I opened my receiver to test these resistors.

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Thursday, August 27th, 2015 electronics 1 Comment

Homebrew Stereo Gainclone Amplifier

LM3886T/NOPB

LM3886T 68W Audio Amplifier (Newark)

In 2012, one of my posts were featured on Hackaday, a globally read and frequently updated aggregator of projects that modify, create, and otherwise hack. The traffic this garnered was enough to throw a couple 500 Server errors, but it also resulted in getting the attention of someone at Farnell/Newark.

I was contacted through the comments┬áby a member of the Farnell team, who spent quite some time on my site and was “loving the content”. After further communications, he asked if I would be interested in reviewing products for them. Of course I said yes!

The question was, what would I review? After looking through some of their enormous catalog, I realized I’d rather create something out of the components I reviewed, and discovered the LM3886, a relatively inexpensive 68-watt audio amplifier. This is where the adventure began!

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Wednesday, April 9th, 2014 electronics, projects 2 Comments