• Year
  • 1949
  • Category
  • Television Receiver (TV) or Monitor
  • Radiomuseum.org ID
  • 125155

Click on the schematic thumbnail to request the schematic as a free document.

 Technical Specifications

  • Number of Tubes
  • 37
  • Main principle
  • Superheterodyne (common)
  • Wave bands
  • Wave Bands given in the notes.
  • Power type and voltage
  • Alternating Current supply (AC) / 117 Volt
  • Loudspeaker
  • 2 Loudspeakers / Ø 9.5 inch = 24.1 cm
  • Material
  • Wooden case
  • from Radiomuseum.org
  • Model: Sparton 4940TV - Sparks-Withington Co., Sparton
  • Shape
  • Console with any shape - in general
  • Dimensions (WHD)
  • 26 x 32 x 15 inch / 660 x 813 x 381 mm
  • Notes
  • 10 " mirror-in-lid b/w TV with US standard VHF tuner, mahogany. Channels 2 through 13
  • Mentioned in
  • Volume 7 Set #64 Folder 4912-11 06/1949
  • Author
  • Model page created by a member from A. See "Data change" for further contributors.

 Collections | Museums | Literature

 Forum

Forum contributions about this model: Sparks-Withington Co: Sparton 4940TV

Threads: 1 | Posts: 2

I have this model set and it did operate when I bought it 30 some odd years ago but had a very dim picture. The neat thing about this TV was that the displayed picture was a reverse image so it looked normal when viewed through the mirror in the lid. Anyhow, I finally replaced all the paper and electrolytic capacitors and now there is no raster. I suspect problem is in the high frequency H.V. Power supply. It consists of a 6SN7 hooked up for parallel operation of a oscillator tuned to about 300khz feeding into primary of the high voltage transformer which has a secondary consisting of multiple separated windings to minimize corona discharge. The power supply appears to be operating correctly but the resistance reading of the secondary is about 560 ohms and that seemed a little high. Does anyone know much about these long forgotten H.V. Power supplies used in early TV or have any info about this particular set? Any insight would be appreciated. 
 

Gregory Jones, 09.Jul.15

Weitere Posts (2) zu diesem Thema.