With a 475 V supply, this amplifier published in Radio Electronics magazine in January 1958 offered good power. The amplifier used 4 tubes.
This circuit is from a Popular Electronics of December 1993. In it we have the way to externally connect...
With this power supply it is possible to use automotive devices with currents up to about 8A on the...
This circuit was found in a 80’s American documentation. The adjustment trimpot is from 47k to...