|
Tubes Asylum Questions about tubes and gear that glows. FAQ |
|
|
|
Tubes Asylum Questions about tubes and gear that glows. FAQ |
|
In Reply to: " :Rectifiers were next to be developed " posted by FenderLover on October 20, 2012 at 09:01:54:
remember that I'm an old man
Early radios basically ran off of batteries and had A, B and C battery supplies. You can see this on old 5 tube radios in those huge shoebox cabinets. AC power came later and if you read the early ads, were primarily used for lighting only. I have pre 1920 radio magazines that advertise special adapters for your light socket to split the AC to a transformer and thus provide for your radio needs (no duplex outlets back in the early days).
Again the proliferation of battery radios and then the advent of AC meant that you had to rectify the B+ voltage to replace the B battery. You can see this on some military type radios and walkie talkies (B+ battery supplies).
The 6.3 volt filaments are not necessary for home use, but necessary for military application in their vehicles.
In fact there are a number of odd filament voltages for tubes. I have 115 volt filaments and you also have to realize that manufacturers eventually would string the filaments of the tubes in series to get a 115/120 volt draw and thus avoid the need for a transformer.
For example you could string two 50L6's in series with several 12AX7's in 6 volt configuration and get basically 120 volts so a filament transformer would not be necessary. Damper diodes were designed for this use, and you see it often in older TV sets.
Stu
This post is made possible by the generous support of people like you and our sponsors:
Follow Ups
- You gotta - unclestu52 10/20/1209:29:56 10/20/12 (3)
- You still gotta - Alpha Al 09:53:05 10/22/12 (0)
- Ah! That makes sense. - FenderLover 09:43:12 10/20/12 (1)
- Stu... BTW - FenderLover 10:24:06 10/20/12 (0)
Top of Page ]
[ Contact Us ]
[ Support/Wish List ]
[ Copyright © 2024, Audio Asylum, all rights reserved ]
