Jara "Krysatec" ("Rat") from Czechia
6h16b Tube Radio
Last night I built my new receiver with a tube! I don'thave any photos now, because I don't have a camera, but if you are interesting also in photos, I can send photos next week.
I'm sending you a schematic of simple receiver with russian tube 6H16b (6N16B). I dont know it sure, but I think this tubes was used for instance in old MiGs (Mikhojan-Gurewitsch) jet figters.
Maybe it will be interesting to you, because result is very good! Sensitivity is better as my reflex with two Ge transistors with feedback, selectivity too, I think, that only audio volume is a little lower. But you can use 15V voltage (you must change resistor 15R and use cca 20R!) and here is audio volume the same as with transistors. Positive feedback is very good, very fine, I think as in Ramon´s transistors receiver. Only one problem is high current for the heater (400mA) , but I don't have other better tube for tests.
I use only one voltage, 12V for all, heating voltage is 6V and I use resistor serial with the heater. Other and better idea is 7806 stabiliser. You can use also 24V voltage with him.
Jara "Rat" Czechia