skal1
Well-known member
Hi
i have just finished building the 670 signal amp with 4 valves a side , and i was wondering what class it should be operating in class A or AB1
input TX 600:10k
output TX :10k:600
at the moment i am using the 670 biasing configuration -6.2Rms on the input tx centre tap to the grid's and -6.2v Rms and ground to the dual 100 pot with the 680 cathode resistors.
The tube i am trying to use has an Anode voltage of 250v Current of 8mA and Cathode resistor of 250 ohm s ,this is 1 tube so my thinking is that i will have to divide the current my 8 and i will have to scale the cathode resistor by 8 as well , am i missing something .
cheers
skal
i have just finished building the 670 signal amp with 4 valves a side , and i was wondering what class it should be operating in class A or AB1
input TX 600:10k
output TX :10k:600
at the moment i am using the 670 biasing configuration -6.2Rms on the input tx centre tap to the grid's and -6.2v Rms and ground to the dual 100 pot with the 680 cathode resistors.
The tube i am trying to use has an Anode voltage of 250v Current of 8mA and Cathode resistor of 250 ohm s ,this is 1 tube so my thinking is that i will have to divide the current my 8 and i will have to scale the cathode resistor by 8 as well , am i missing something .
cheers
skal