textile wrote:They work as 2sc1583 :shock: , put them in place and they work as normal 2sc1583 , did sound recordings back to back no difference!!
So its not all bad , just goes to show that re-stamping is quite common.
I wonder if these are re-re-stamped 2SC1583 52G that Gaetano was talking about. The reason being after I saw his thread on those the other day, I looked and found two with the 52G marking in my stash. They were the correct pin-out, but the Hfe measured around 350, when the Hfe on a couple of the "vintage" 1583's I have measured in the mid 600's. Swapping those back and forth made a big difference in the sound, especially noticeable when swapping them back and forth as the differential amp/buffer of the filter. The least difference, basically inaudible, was in the VCO.
Don Taylor, a.k.a. Brassteacher
"Jack of all trades, master of none, proficient at even fewer..."