Amps is back up and running after C6 bit the dust and in setting everything up I pulled the meters out and spent some time making sure all is set and stable.
I have a few different 5U4G rectifiers and I noticed that the Raytheon has lower B+ voltage the the two RCA's, 248-250 vs. 282-286. In deciding to leave the lower volt rectifier in there I spent some time getting the bias set where it sounded the best. 32mA was the ticket.
If I decide to run one of the higher voltage rectifiers should I reduce bias? Hot hot is too hot? What about tube life?
I believe I understand the principal of bias just looking for the practical. I also have read Georges suggestion of where to bias a 45 amp in Tubes and Applications.
Why does suggested bias go down at higher voltages?
Thanks,
Walt
I have a few different 5U4G rectifiers and I noticed that the Raytheon has lower B+ voltage the the two RCA's, 248-250 vs. 282-286. In deciding to leave the lower volt rectifier in there I spent some time getting the bias set where it sounded the best. 32mA was the ticket.
If I decide to run one of the higher voltage rectifiers should I reduce bias? Hot hot is too hot? What about tube life?
I believe I understand the principal of bias just looking for the practical. I also have read Georges suggestion of where to bias a 45 amp in Tubes and Applications.
Why does suggested bias go down at higher voltages?
Thanks,
Walt
Voltage x current = plate dissipation power. Max value is in datasheet, it is not recommended to exceed it.
You may have read this already but I think it explains well how the tube dissipation and voltage don't always go up in line with each other.
Idle Current Biasing - Why 70 percent?
I can't say that I can follow it all but I am picking up bits and pieces of it.
I am just starting a SSE build so I'm trying to learn myself.
Idle Current Biasing - Why 70 percent?
I can't say that I can follow it all but I am picking up bits and pieces of it.
I am just starting a SSE build so I'm trying to learn myself.
Good article GCOM but I believe the TSE is a class A amp tubelab recommends to run the tubes bias 28-30 mA where data sheets indicate 34mA as the top. I get that running the tube 'hot' may decrease life but is this the reason for the lowered recommended bias.
cold vs hot
heaters determine the activity of the moment, & over time their perform does lessen, so, every aspect, to emphasize their longevity has been incorporated, e.g., thorium filament coat, dc drive, possibly boost plate tension
heaters determine the activity of the moment, & over time their perform does lessen, so, every aspect, to emphasize their longevity has been incorporated, e.g., thorium filament coat, dc drive, possibly boost plate tension