updated 30-11-99
pictures available for:
Hytron
Sylvania type 1
Sylvania type 2
TungSol
Western Electric
National Union
Raytheon
Philco (NU)
Senco (NU)
Raytheon 6A3 single-plate
National Union 6B4G single-plate
National Union VT25A
Hytron (for WE) VT25A
HYTRON





SYLVANIA
type 1





SYLVANIA
type 2
TUNGSOL





WESTERN ELECTRIC



NATIONAL UNION



RAYTHEON




PHILCO
same as Senco but with Philco label on base
SENCO



RAYTHEON
single plate 6A3
pictures courtesy of Walter Clay



Appearance is identical to the type 2 Sylvania VT52 which also has the ceramic supports.
NATIONAL UNION
single plate 6B4G
pictures courtesy of Walter Clay



Appearance is identical to the WE, NU, Philco and Senco VT52
© Jim de Kort