Power triode for last stage audio Power Output
UX245 = PH245 = F203 = G45 = MX245 = EX645 = JX245 = Z-45 = PM245 = R45_Rogers = GSX245 = RayX-245 = NU-45 = C-245 = PA245 = TS-245 = 445 = SX245 = 245-C = L45 = 57T245 = CX345 = GX245 = AC45 = ER45 = 145 = T-45 = VX245 = A.C.245 = RYB245 = NX-245 = ER245 = DX245 = AX-245 = TC245 = TX-45 = 245 = 45 = P245 = X245
SImilar tube: F203A ; FR-301
First serie March 1929
Evolution 2A3
Socket type UX-Base 4 Pins (2 thick)
Filament heater Vf 2.5 Volt / If 1.5 Ampere / Direct / Specified voltage AC/DC
According to Tyne, page 322, this audio-power output tube was introduced in March 1929. It is intermediate between UX171A and UX210 and was first named UX245, later in short 245 and 45. See other identical denominations too. The oxide-coated filament operates at 2.5 volts AC or DC, taking 1.4 amperes. The anode is of sheet nickel, carbonzed fo facilitate radiation. Power output about 0.8 watt. The tube was not yet listed in March 1929 GE tube history, which gives introductory dates for all their tubes up to that time.
Dimensions incl.pins/tip 137 x 54 mm / x 5.39 x 2.13 inch
weight 68 g / 2.40 oz