Majestic 181 Ch= 180

Grigsby-Grunow (-Hinds) Co. (Majestic pre 1933); Chicago (IL)

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  • Year
  • 1929
  • Category
  • Broadcast Receiver - or past WW2 Tuner
  • Radiomuseum.org ID
  • 43608

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

 Technical Specifications

  • Number of Tubes
  • 9
  • Main principle
  • TRF without regeneration; 3 AF stage(s); Neutrodyne
  • Tuned circuits
  • 4 AM circuit(s)
  • Wave bands
  • Broadcast only (MW).
  • Details
  • Record Player (not changer)
  • Power type and voltage
  • Alternating Current supply (AC) / 90-130 Volt
  • Loudspeaker
  • Electro Magnetic Dynamic LS (moving-coil with field excitation coil) / Ø 8 inch = 20.3 cm
  • Material
  • Wooden case
  • from Radiomuseum.org
  • Model: Majestic 181 Ch= 180 - Grigsby-Grunow -Hinds Co.
  • Shape
  • Console, Lowboy (legs < 50 %).
  • Notes

  • This radio is a cascade of 3 individual TRF stages, each with its own feedback coil forming a Wheatstone bridge acting as a Hazeltine neutralization for the triode (described as the RFL circuit in contemporary sources). The feedback polarity is reversed with respect to the signal polarity through the Cag Miller-capacitance, in effect neutralising the triode tendency to oscillate.

    The antenna circuit has a separate tuning coil, to be readjusted with each tuned frequency.

    The tuning scale is graduated with 2 scales: One in frequency from 550 to 1500 kHz and the other as a linear scale from 0 to 100. 

    LF coupling between stages is done by transformers - Push-pull output.

    The unit contains a separate 8P6 or 8P3 power supply unit with individual transformers for the filaments and the 425 Volt anode supply. A current regulator is included in the primary circuit of the power transformers to compensate for mains voltage changes between 90 and 130 Volt AC.

  • Price in first year of sale
  • 265.00 $
  • External source of data
  • Ernst Erb
  • Circuit diagram reference
  • Rider's Perpetual, Volume 1 = 1931/1934 (for 1919-1931)

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