#8796
Guenther
Participant

    Hello Frank,

    You may use AC127 or any other available Ge NPN Transistor (early Japanese types started with 2SD..). I checked the hfe values of my NPN transistors and decided to use the above mentioned ones because of their hfe >220 – my AC127 etc. as low power / switch types had around hfe 100.

    Good luck,

    Guenther