Majestic 181 Ch= 180
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| Year: 1929 | Category: Broadcast Receiver - or past WW2 Tuner | ||||
| Valves / Tubes | 9: 27 27 27 27 27 50 50 81 81 |
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| Main principle | TRF without regeneration; 3 AF stage(s); Neutrodyne |
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| 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 |
| Power out | |
| from Radiomuseum.org | Model: Majestic 181 Ch= 180 - Grigsby-Grunow -Hinds Co. |
| Material | Wooden case |
| 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 $ |
| Collectors' prices | |
| External source of data | Ernst Erb |
| Source of data | Radio Collector`s Guide 1921-1932 |
| Circuit diagram reference | Rider's Perpetual, Volume 1 = 1931/1934 (for 1919-1931) |
| Mentioned in | The Radio Collector's Directory and Price Guide 1921 - 1965 |
| Literature/Schematics (1) | Rider's Perpetual, Volume 2 = 1932 and before |
All listed radios etc. from Grigsby-Grunow (-Hinds) Co. (Majestic pre 1933); Chicago (IL)
Here you find 200 models, 118 with images and 154 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
