[Amps] Maintenance-free

[Steve London]

On 02/27/2017 10:55 AM, Jim Brown wrote:
> Yes, the control circuitry is quite complex, and I wouldn't want
> to work on it. But that control circuitry can prevent a lot of damage,
> and can make tubes last longer by going into protect mode when grid
> current rises.

There are very simple ways to automatically bypass the amp when the grid 
current becomes excessive. Here's an example : 
http://www.k6xx.com/radio/76a_prot.pdf

73,
Steve, N2IC