Beschrijving
Early military grade version of the 12AT7WA, made by Raytheon in 1962 in the USA
This is a military grade version of the 12AT7WA /6201 tube, meaning that the tolerances are specified more strictly. The code on the glass 62-20 280 indicates that the tube is produced in 1962 in the Raytheon plant in the USA. The tube has a tilted halo getter, a half box plate structure and back plates, see pictures. Very healthy tube!
The JAN-CRP-12AT7WA is a military specification of the ECC81, which means that this tube has stricter quality and reliability requirements than the standard ECC81. This often makes the JAN-CRP-12AT7WA a better choice for applications where reliability and quality are crucial.
Sonics
I have no information about the Sonic performance of this tube.
Test results*
The tube tests NOS. The internal balance between the triode sections is good. The measurement data below illustrate that the tube is in excellent condition.
| Valve
V46 |
Ia (plate current):
Transconductance (Gm): Gas test, Shorts test: |
10,6 / 10,6 mA
5,7 /5,8 mA/V OK |
= NOS / NOS
= NOS / NOS
|
Where NOS is : Ia = 7 to 14 mA, Gm= 4,5 to 6,5 mA/V.
* For test methods and factory specification read the tube testing page.
Short description
| Tube type | JAN-GRP- 12AT7WA |
| Quantity of Tubes | One tube |
| Brand | General Electric |
| Manufactured in | USA |
| Date codes | 62-20 (1962) |
| Construction | Half box plates, triple micas, Black plates |
| Getter Construction | Slanted halo |
| Print Condition | Good; see pictures |
| Box included | Generic white box |
| Equivalent tubes: | 12AT7, ECC81, 12AT7WA, ECC801S |
| General test results | NOS |
