The PL802T is a solid state plug-in replacement for the valve. The 56 Ω resistor is rated at 15 Watts and is required as the original would be used with a 300 mA series heater chain. The active device is a BF459 300 Volt NPN power transistor.
Solid state replacements for valves had a short period of popularity and were most successful as rectifier replacements. SeeCV7136.
The 56 oam wire-wound power resistor.
The back of the heat-sink with the transistor leads passing into the 30 x 30 mm fibre-glass PCB.
The maker is the Brazilian company Dallem.
The other side of the box. The box measures 32 mm square and 77 mm tall.
The box lid with the Type designation paper label.
The heat sink and board is 30 mm in square, and excluding the base pins is 70 mm tall.
