My RV12P4000 tubes

The RV 12 P 4000 vacuum tube is described in detail on this page.

The four original "RV 12 P 4000" vacuum tubes of my Feld-Hell machine, plus some of my spares

Below are two or three close-up photos of each of my RV 12 P 4000 tubes, showing all their markings. They are listed in chronological order, based on their date of manufacture.

[1937 - nr. 1]
[1937 - nr. 2]
[1940 - nr. 1]
[1940 - nr. 2]
[1940 - nr. 3]
[1940 - nr. 4]
[1941 - nr. 1]
[1941 - nr. 2]
[1942 - nr. 1]
[1943 - nr. 1]
[1943 - nr. 2]
[194?]

1937 - nr. 1

Markings:

Manufacturer: Telefunken
Date codes: 27/37 and 12. Juli 1937 and 121632
Eigentum-stamp: Wehrmachteigentum
Waffenamt-stamp: Wa.A.338
Extraction-knob insert: black octagonal Telefunken logo
Other observation: white plastic disk at top

1937 - nr. 2

Markings:

Manufacturer: Telefunken
Date codes: 31.37 and 17. Aug. 1937 and 1254
Eigentum-stamp: Wehrmachteigentum
Waffenamt-stamp: Wa.A.338
Extraction-knob insert: black octagonal Telefunken logo
Other observation: pointed grid pin

1940- nr. 1

Markings:

Manufacturer: Valvo
Date codes: 11/40
Eigentum-stamp: Wehrmachteigentum
Waffenamt-stamp: Wa.A.745
Extraction-knob insert: black octagonal Telefunken logo
Other observation: white plastic disk at top

1940- nr. 2

Markings:

Manufacturer: Valvo
Date codes: 11/40
Eigentum-stamp: Wehrmacht
Waffenamt-stamp: Wa.A.745
Extraction-knob insert: black Valvo logo
Other observation: white plastic disk at top

1940 - nr. 3

Markings:

Manufacturer: Telefunken
Date codes: 24/40 and 192248
Eigentum-stamp: Eigentum RLM
Waffenamt-stamp: none
Extraction-knob insert: black square Telefunken logo
Other observation: white plastic disk at top; unusual is that the Eigentum stamp is magenta, and that there is no WaA stamp on this tube

1940 - nr. 4

Markings:

Manufacturer: Telefunken
Date codes: 24/40 and 192413
Eigentum-stamp: Eigentum RLM
Waffenamt-stamp: none
Extraction-knob insert: black square Telefunken logo
Other observation: white plastic disk at top; unusual is that the Eigentum stamp is magenta, and that there is no WaA stamp on this tube

1941 - nr. 1

Markings:

Manufacturer: Valvo
Date codes: 08/41
Eigentum-stamp: Wehrmachteigentum
Waffenamt-stamp: WaA 745
Extraction-knob insert: black Valvo logo
Other observation: factory code "H" and "2"; white plastic disk at top

1941 - nr. 2

Markings:

Manufacturer: Valvo
Date codes: 16/41
Eigentum-stamp: Wehrmacht
Waffenamt-stamp: WaA 745
Extraction-knob insert: black Valvo logo
Other observations: factory code "H" and "4"; white plastic disk at top

1943 - nr. 1

Markings:

Manufacturer: Valvo
Date codes: 43/43 and 43/43
Eigentum-stamp: Wehrmachteigentum
Waffenamt-stamp: WaA 745
Extraction-knob insert: black Valvo logo
Other observations: brown disk with 2 additional holes; factory code "H"

1943 - nr. 2

Markings:

Manufacturer: TeKaDe
Date codes: 15.11.43 and 47/43
Eigentum-stamp: Wehrmacht
Waffenamt-stamp: Wa. A. 836
Extraction-knob insert: dark green TeKaDe logo
Other observation: dark brown/black disk

194?

Markings:

Manufacturer: Valvo
Date codes: 11/4 and 13/4 (note: single-digit year-code)
Eigentum-stamp: Wehrmachteigentum
Waffenamt-stamp: WaA 745
Extraction-knob insert: uncolored ( = bakelite) Valvo logo with painted green dot
Other observation: steel sheet metal perforated sleeve