03-07-2021, 11:45 AM
Ok so the difference two things.
1. By having a ct on the ac heater winding it's use to balance the 60 cy out hum.
2. By not having a ct it's cheaper as you can save on the cost on wire to connect one side of the heater back to the transformer rather than just grounding it.
Sets that use a regenerative detector are prone to pickup hum from any sort of ac field so shielding and decoupling are important. It's akin to a tube in a high gain audio amplifier. Put your hand near it and it hums. Wack it with your finger it rings like a bell. Both the high amp and regen det are typically on the hairy edge of stability do to they high value control grid resistor.
1. By having a ct on the ac heater winding it's use to balance the 60 cy out hum.
2. By not having a ct it's cheaper as you can save on the cost on wire to connect one side of the heater back to the transformer rather than just grounding it.
Sets that use a regenerative detector are prone to pickup hum from any sort of ac field so shielding and decoupling are important. It's akin to a tube in a high gain audio amplifier. Put your hand near it and it hums. Wack it with your finger it rings like a bell. Both the high amp and regen det are typically on the hairy edge of stability do to they high value control grid resistor.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
