05-07-2013, 10:57 PM
I would not recommend using a solid state replacement for the 5Y3.
The problem is that the SS rectifier will increase the B+ voltage. The 5Y3 has a certain voltage drop which was taken into account when the set was designed to provide the proper voltage output. Since the SS rectifier has a much lower voltage drop, the voltage output will be much higher. So although the 5Y3 will not be generating heat, the rest of the radio's parts and tubes will be getting hotter due to overvoltage thereby reducing their life.
In effect, the 5Y3 acts as both a series resistor and a rectifier, which is why it gets so hot.
The problem is that the SS rectifier will increase the B+ voltage. The 5Y3 has a certain voltage drop which was taken into account when the set was designed to provide the proper voltage output. Since the SS rectifier has a much lower voltage drop, the voltage output will be much higher. So although the 5Y3 will not be generating heat, the rest of the radio's parts and tubes will be getting hotter due to overvoltage thereby reducing their life.
In effect, the 5Y3 acts as both a series resistor and a rectifier, which is why it gets so hot.
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