You remember what National Radio Schools called the crystal lamp bulb, in their single tube CONAR 500 transmitter?

I don’t either, but it was something like “special variable resistance device” .  Sounds good in the ads, anyway.

But, come to think of it, it works as a current limiter only. I think your idea of a fixed resistor is  better. It’s resistance

does not decrease with the current.

-Hue Miller