• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Brightest heaters in tubes?

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Hello Tyne,

The 812A has a Thoriated-tungsten-filament and illuminates very brightly but is seldom used in audio work. I have a pair that some day I will play with. These direct heated power triodes were most commonly used in early modulators, AF pwr amps and transmitting RF application back in the 1940's. Mickeystan
 
The 812A has a Thoriated-tungsten-filament and illuminates very brightly but is seldom used in audio work.

Most thoriated tungsten filaments are rather bright. The 211 and the 845 light up rather well.

845 - looks like a light house......10V @ 3A is 30 Watts of glow.

Actually its 10 volts at 3.25 amps. There is two of them running here. That and the computer monitor are the only lights in the room.

GM-70. 20V@3A = 60W, almost like light bulb...

The 833A has a 10 volt 10 amp filament for 100 watts, but it also makes a good room heater.
 

Attachments

  • 845glow1a.jpg
    845glow1a.jpg
    49.4 KB · Views: 227
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.