PRO37.1 Follow the mod info for the PR0-34 except remove diode D13 on the cpu board. This is the lower of the two diodes (D12, D13). Don't waste time prying any shields off as some mod info may say to do, just remove the 3 screws holding the frame to the cpu board, swing the frame out of the way. Change capacitor C-170 on the linear board from 0.047 uf to 0.10 uf for better audio quality. This cap is near the big 16 pin detector chip IC-101 and is a (relatively!) large mylar unit on the component side of the board. Upping its value raises the low end audio a little, enough so it won't hurt your ears if you have sinus problems. Hi. 73 de Bill in Golden, CO