5UP1

1. f = HEATER (filament)
2. G = GRID
3. K = CATHODE
4. F = ANODE NO.1 (focus)
5. no connection
6. Y1 = D3
7. Y2 = D4
8. A = ANODE NO.2 (anode)
9. X2 = D2
10.X1 = D1
11.nc
12.f = HEATER