• Year
  • 1947–1952 ??
  • Category
  • Loudspeaker, headphone or earphone
  • Radiomuseum.org ID
  • 172198

 Technical Specifications

  • Wave bands
  • - without
  • Power type and voltage
  • No Power needed
  • Loudspeaker
  • Permanent Magnet Dynamic (PDyn) Loudspeaker (moving coil) / Ø 8 inch = 20.3 cm
  • Material
  • Metal case
  • from Radiomuseum.org
  • Model: Dynamic Reproducer 8H - Rola Company AUS Pty. Ltd.;
  • Shape
  • Chassis only or for «building in»
  • Notes
  • The power handling capacity of Model 8H is similar to that of the Model 6H, but the frequency response of the 8-inch loudspeaker is wider than that of the 6H. Thus, though it's applications are similar to those of Model 6H, it finds special use in high quality AC operatated mantel receivers. The extended frequency range of Model 8H, coupled with it's electro-acoustic qualities, has been responsible for this loudspeaker's inclusion in some of the best of Australian made battery operated portables.

    Power Handling Capacity 4 watts
    Fundamental Diaphragm Resonance 106-115 c.p.s. (Hz) (F81 Cone).
    Voice Coil Impedance 3.7 ohms at 400 c.p.s. (Hz)
    Transformer D. type Isocore transformer, attatched or detatched for chassis mounting.
    Principal Dimensions Overall diameter of diaphragm housing .. .. .. .. .. ..  8 1/16"
    Diameter of baffle opening .. .. .. .. .. .. .. .. .. .. .. ..  7"
    Diameter of voice coil .. .. .. .. .. .. .. .. .. .. .. .. .. ..  ¾"
    Depth from pad-ring to rear, including transformer .. 3¾"
    Mounting Four slots spaced 90º apart on a 7 19/32" pitch circle diameter. Dimensions of the slots 5/16" x 7/32". A speaker mounting bracket is fitted on the front plate can be provided if required.
    Finish Diaphragm housing bright cadmium plated; magnet black and lacquered, transformer can silver lacquered.
    Weight 1 lb. 14¼ ozs. (including transformer).

    REPLACEMENT INFORMATION

    Model 8H can be used as a replacement for the electro-dynamic Model F8 and for the PM types, Model 8/11 and Model 8/15. When used to replace Model F8 a Type 14/60 choke will be needed and the difference between the resistance of this and that of the F8 field winding will need to be made up with a wire-wound resistance of suitable watt rating.

  • Net weight (2.2 lb = 1 kg)
  • 1 lb 4 oz (1.25 lb) / 0.568 kg
  • Literature/Schematics (1)
  • - - Manufacturers Literature (Rola Loudspeaker Data. (Date unknown))
  • Author
  • Model page created by Aglef Tröger. See "Data change" for further contributors.

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