Dave's Antique Radio & TV Restorations
P.O. Box 285
Liverpool, NY 13088-0285

dave2@tubesandtransistorsandmore.com  dave2@dreamscape.com
All  American  Tubes
Information page

It's sometimes difficult to tell if your 5 or 6 tube radio contains All American tubes.
 That's why I created this page.

Six Tube All American Radios contain these 6 types of tubes:

1.) RF Amplifier, 2) mixer/oscillator (aka. Converter or First Detector), 3) RF Amplifier,

4) Detector/First AF/AVC (All three in one), 5) Amplifier, and a 6) rectifier.

This is how they are described on tube charts inside or on the bottom of a radio.

Five tube All American Radios do not contain the RF amplifier tube.

In most cases an All American 5 or 6 Tube radio contains tubes that look like these:

      Octal base All American Tubes

12SK7            12SA7      12SQ7     35Z5      50L6

          Metal 6K7  (12K7 looks lik this too)        6Q7 (12Q7 looks like this too).           Metal 6SA7 (12SA7 also looks like this)

The most common tube line-up 12SK7, 12SQ7, 12SA7, 50L6 and 35Z5.
There were earlier versions of the 12SK7 and the 12SQ7.
These were the 12K7 and 12Q7.

A 12SK7 is an IF or RF amplifier.
A 12SA7 is a converter/oscillator tube.
12SQ7 is a detector/1st AF/AVC tube.
A 50L6 is an audio amplifier tube.
A 35Z5 is a rectifier tube.

Also, some tubes' filaments worked on 6 volts instead of 12 volts
(for example 6SK7, 6SA7, 6SQ7).

In addition to the 50L6, there was a 25L6, and a 35L6.
In additon to the 35Z5 was a 45Z5.

Three of the tube types are available in metal.

So to tell that you have the All American Octal tubes, look for "A7", "K7", "Q7", "L6" (25, 35, or 50), and "Z5" (25, 35 or 45).
Also check the tube chart for tube types.

Before the "Z5" was used, there was a 25Z6.

When a 25Z6 was used, a ballast tube was used, so that the radio could also have a dial lamp.
Sometimes the 25Z6 was used in a voltage doubler circuit.  This stepped up the voltage without using a power transformer.

In pricing the special, I count a voltage doubler circuit as radio having a power transformer.

 Loktal base All American
50A5 Loktal Tube
Loktal tubes
This is a typical tube line-up for Loktal tubes:

14Q7, 14A7, 14B6, 50A7, and 35Y4

14A7 is an RF or IF amplifier.
14Q7 is a Converter/oscillaton tube.
14B6 is a detector/1st AF/AVC tube.
50A5 is an audio amplifier tube.
35Y4 is a rectifier tube.

There are other loktal tubes that are the equivalent to the ones listed above.
Check the radio's tube chart. It should identify the type of tube.

The tubes with a 14 in front actually have 12 volt filament.
Tubes with 7 in front actually have a 6 volt filament.
The 7 and 14 indicate a Loktal tube.

Miniature All American tubes

12BE6        12BA6     12AV6   50C5   35W4

The most common line up of miniature All American tubes is:

12BE6, 12BA6, 12AV6, 35W4, and 50C5

A 12BA6 is either an RF or IF amplifier.
A 12BE6 is a Converter/Oscillator.
A 12AV6 is a detector/1st AF/AVC tube.
A 50C5 is an audio amplifier tube.
A 35W4 is a rectifier tube.

There was also a 50B5.  There might also be a 12AT6 instead of the 12AV6.
There are other equivalent miniature tubes.  These are the most common.

As with the octal tubes, there were 6 volt counterparts to the 12 (for example 6BA6, 6BE6, 6AV6).

A set may be comprised of all Octal tubes, all miniature tubes or all Loktal tubes.  There may also be times when they are mixed together in the same radio.

A good way to tell if your radio doesn't have a power transformer, is to look at the Rectifier Tube number. If it starts with a 35 (35Z5, 35W4), chances are that the radio doesn't have one. 

If, on the other hand, it has a tube number like 5Y3, or 6X5, it has a power transformer, and will cost $10.00 more for the special.

Back to my All American Radio restorations specals page

Page created: July 27, 2004 Last updated on the tubesandtransistorsandmore site: December 29, 2009 at about 10:15 PM.