Conclusion
The GU-81M is really beautiful, and a real pièce de
résistance in my small by growing collection of rare valves.
Rare is perhaps not the right word according to Franz
Hamberger who said that this valve is readily available "for an apple and an
egg" as he described it.
The GU-81M is an equivalent to the old Telefunken RS384.
It might be a rare collectible one day, but I keep it just for
the sake of preserving history for future generations.
I would like to thank Franz Hamberger for the information
about the GU-81M valve, and that he allowed me to use the base diagram and maximum ratings
parameters from his site.
Best regards,
Mats Wiklander, 1999-11-27 |