TUBES


THis document is intended to show case a small cross section of tubes used in early radio equipment.
The Radio Valve Company of Canada (RVC) was incorporated in November 1922 and it manufactured vacuum tubes under the trade name "Radiotron".  These tubes were distributed to the radio trade excusively by the Canadian Marconi Company and Canadian General Electric.
1920s or Earlier
q_tube_1.jpg
Marconi 'Q' Tube (See credit #2)

Introduced in 1916, this is  triode with widely positioned leads to minimize inter-electrode capacitance. It was a high impedance tube, used primarily as a detector. Like all early Marconi valves, it was made originally by Edison Swan but after 1919 by M-OV. 

Filament: 6 VDC @ 0.4 amps
Plate voltage: 150 to 200 volts as an amplifier; 25 to 30 volts as a detector. 

v24_tube.jpg
Marconi 'V24' Tube.  (See credit #2) 

This tube, a directly heated triode, was a development of the 'R' type aimed at improving high frequency performance. The V24 was introduced in 1916 by Marconi UK and was used as an RF amplifier.. Filament needs 6 volts at 0.7 Amps with an anode voltage of 24 volts, hence the name V24. 

A more detailed view of the V24 tube. So far, there is no evidence to show that any of these tubes were manufactured in Canada earlier than the latter part of 1921 according to Radio Trade Builder magazine ,December 1934.(Photo by Lewis Bodlin)
tube_holder.jpg
This is an adapter for socketless tubes such as the V24. (Image provided by Lewis Bodkin) 
tube_holder_02.jpg
This adapter for socketless tubes would have been used in radios that employed the breadboard techique of fabrication. Image provided by Lewis Bodkin) 
tube_holder_100_3357b.jpg
This adapter facilitates the mounting of a socketless tube in a horizontal position. (Image provided by Lewis Bodkin) 

 
Type: UV-201 receiving triode. 
Filament - Pure tungsten. 5 volts@ 1 amp. 
Plate Voltage ? 
Amplification factor: ? 
Vintage: 1922 
Comment: The UV prefix indicates a base with four short pins. 
 Introduced in 1922, the UV201A  uses a thoriated tungsten filament which only draws 250 ma. (Photo by Louis Bodkin)

1930s or LATER

12a_tube.jpg
Type 12A triode (Ebay photo)

 
1c21_tube.jpg
1C21 Thryatron 

 
1625_tube.jpg
1625 beam power tetrode 
832_tube.jpg
832A transmitting tetrode
6sn7_tube.jpg
6SN7 dual triode
12av6_tube.jpg
12AV6  Double diode and triode
12sa7_tube.jpg
12SA7 - Sincle ended series example
All photos in this table by Pierre Lewis

 
marconi_tubes_6l5.jpg
6L5G Power Triode Amplifier 
marconi_tubes_12bz7.jpg
12BZ7 high-Mu twin triode 
marconi_tubes_6397.jpg
6397- Power Amplifier Pentode 
marconi_tube_1a.jpg
Might be a 1A5 but the box is very historical.
6af6.jpg
6AF6 miniature, octal, magic eye tube.
All photos in this table via E-bay

 
12sc7.jpg
This example of a 12SC7 tube, was built under contract and was common to all the Canadian Forces. The 12SC7 is a hi-Mu twin triode. (E-bay photo)
5961_tube.jpg
This 5961 tube, packaged generically,  was built specifically for the RCN in February  1959. (Photo by Tom Brent)  

 
6204_tube.jpg
This 6204 tube with a blue finish was never registered, but it is a 6.3 volt, half wave rectifier that is equivalent to one half of a type 6X5. 

The 5961 tube, also painted blue is described as as "Canadian reliable 6SA7".

Marconi made a 6006 tube whose finish was red. This is identified as a "ruggedized remote cutoff pentode (Canadian) version of the 6SG7". 

The 5961 and 6006 tubes mentioned above were referenced from : MIL-HDBK-213, "Electron Tubes Interchangeability Directory" published by the United States Department of Defense and dated November 02, 1959

 
marconi_tube_carton.jpg
A more contemporary tube carton. (E-bay photo)

 
Contributors and Credits:

1) Pierre Lewis <leware(at)videotron.ca>
2) V24 and 'Q' photos by Ben <benam(at)rogers.com>
3) V24 Description http://www.r-type.org/exhib/aaj0135.htm
4) http://www.oneillselectronicmuseum.com/largephotos/decorphoto/marconiad1a.jpg
5) http://www.g3ngd.talktalk.net/marconi.html
6) http://www.r-type.org/articles/art-002.htm#03
7) Tom Brent <navyradiocom(at)gmail.com>
8) “The Early Development of Radio in Canada 1901-1930 by Robert Murray”.
9) Jim Cross <jimcross(at)cfl.rr.com>
10)  Lewis Bodkin  <05bodkin555(at)gmail,com>
11) V24 and Q tube specs: Scientific Experimenter March 1921
12)  Lewis Bodkin  <05bodkin555(at)gmail.com>


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Sept 8/18