Old thread but these SQB receivers / duets still exist and work fine everywhere so... My original PSA05R-090 adapter is failing, giving up the ghost too now, in the Spring of 2021. I remember that I had a few new RadioShack power adapters from when they closed down a few years ago. I also had a bunch of their interchangeable cord tips at hand in our garage. A smaller yellow one from the collection does the job admirably, powered from a 6V-800mA PA (vs the Duet stock 560mA). It has (approximately?) the 3.5mm OD & 1.05 ID required by the Duet. The receiver stayed cool after hours of testing initially and now in normal operation. Fortunately, I found in the same box another 273-1761. Since I have a 2nd Duet in our master bedroom I'm saving it for when the same need arises, soon probably (I've had those Duets since early 2009). You could also use a R.S. model 273-1770 PA which is a more closely matched adapter (9V as the stock one, and 800mA) if you have or find one on eBay, etc. The problem here is to match it with the correct smaller interchangeable yellow plug needed. I'm in the U.S. and could have purchased a couple of the 'stock' PSA05R-090 with the right connector but it was quite cheaper this way and it's working fine for me as it is.