OT primary impedance for 6K6s

[kodabmx]

The actual patent: Patent Images

I now want to play with idea.

 

[Tubelab_com]

Stick a transistor in place of the 12AU7 and you can patent it again!

But when you make the amplifier that's offered for sale (The Berning EA-230) you use a 6SN7.

Tube amplifiers for high-end audio by The David Berning Company

 

[6A3sUMMER]

One old rule at the patent office:

If a new patent application presents a "new" product, and that "new" product idea is obvious to someone 'well versed in the art', the "new" product was not patentable.

Either the patent office no longer has people 'well versed in the art', or they have changed the rule.

 

[jhstewart9]

It is said that Einstein was not a great student.
But he was trained at the patent office. And great things happened.
That tells us something but not sure what.

 

[PRR]

> they have changed the rule.

Not explicitly. But if it is not drop-dead a copy-cat, the inclination is to demand the full patent fee, issue the paper, and let the lawyers argue it out when infringement is claimed.

 

[6A3sUMMER]

I guess that Einstein was trained by people who were well versed in the art.

No more Einsteins coming out of the patent office.