Looking to sub 2SC971 in a Akai x-165d oscillator board. 2SC971 is a TO-5 device with a heatsink. Service manual I found two possible modern subs: ksc2690 (to-126) and ksc2073 (to-220) 2sc971 Pc = 1W cbv = 50v ebv = 7v Ic max = .5A ft = 30mhz hFE = 80 min ksc2073 Pc = 25W cbv = 150v ebv = 5v Ic max = 1.5A. ft = 4mhz hFE = 40 min ksc2690AYS Pc = 1.2w cbv = 120v ebv = 5v Ic max = .1.2A ft = 155mHz hFE = 160 min ksc2690AYS seems like a closer match, ebv is a little low, pins should fit existing holes but its much faster @155mhz. How would this affect oscillator? Would a heatsink be required for new device since heat dissipation is much better?