Denon AVR-2105 Repair - no display or output

This Denon AVR-2105 was a repair for a family member after 10 years of use. It was a fairly simple issue this time but demonstrates a couple of useful diagnostic techniques. After the repair I did blow out the dust with a compressed air line - normally I would do this up front but the thrill of the chase (and the terrible weather!) meant I dived straight in :) Service Manual: