Fusion 8100 - Repair

[tlawler]

My Emotiva Fusion 8100 stopped working. When powered on (rear switch), the unit correctly selects 115 volts and the power light on the front blinks red a few times then goes to steady red (standby). When the front power button is pressed, the power light turns blue and the display shows “Loading…” but never completely powers on. The 12 volt and 5 volt power regulators are providing the correct voltages. There is a voltage regulator chip on the main board, near the HDMI ports, that should provide 3.3 volts but when tested only shows 1.25 volts. Components on the main board are chip mounted and are difficult to remove and test. I replaced all of the electrolytic capacitors on the 5v/12v power regulator board, all of the 470mf/16 volt electrolytic capacitors on the main board, and the .1mf chip capacitor that is used with the 3.3 volt regulator on the main board. I’ve probably invested too much time trying to fix this unit but it’s like an old friend and I’m not ready to give up on it yet. It would be helpful if I could find a replacement main board, the long pc board at the back of the unit that is connected to the inputs. Is anyone aware of a source for spare parts from discarded Emotiva 8100s?
Thank you!

[tlawler]

I think I figured it out. There is a 3.3 volt voltage regulator (1117) on the main pc board (the top board in the back of the Emotiva 8100, with the HDMI inputs). The voltage regulator is located behind the HDMI-1 input, next to a small vertical pc board and sandwiched between several large capacitors. Locate Pin 2 on the voltage regulator, the large pin on the opposite side from the other 3 pins. That pin was not properly soldered and would cause power anomalies related to heat and flexing the main pc board. I reflowed solder for pin 2 and the 8100 is working again. There is a similar post on stereonet.com:

www.stereonet.com/forums/topic/123327-help-debugging-emotiva-8100-amp-inconsistent-powerup/

The author of that post solved the problem by re-soldering every component on the main pc board. I recommend re-soldering pin 2 on the 1117 voltage regulator first! Good luck!!

[MusicHead]

Thanks for sharing this, it may come handy one day. My 8100 is still going strong, but you never know.

I am very familiar with the 1117 series voltage regulators. The original was from Linear Technology, the LT1117. Nowadays many semiconductor suppliers make "clones". Old designs (more than 25 years) but still quite popular and now it costs next to nothing. When it came out it was quite expensive, one of the first semi-low drop linear regulators after the even older LM78xx and LM317 series.