• País
• Estados Unidos

• Fabricante / Marca
• Grigsby-Grunow (-Hinds) Co. (Majestic pre 1933); Chicago (IL)

• Año
• 1928

• Categoría
• Radio - o Sintonizador pasado WW2

• Radiomuseum.org ID
• 199205

Haga clic en la miniatura esquemática para solicitarlo como documento gratuito.

• Numero de valvulas
• 8

• Válvulas
• UX226 UX226 UX226 UY227 UX226 UX171A UX171A UX280

• Principio principal
• Diseños especiales; 3 Etapas de AF

• Número de circuitos sintonía
• 4 Circuíto(s) AM

• Gama de ondas
• OM (onda media) solamente

• Tensión de funcionamiento
• Red: Corriente alterna (CA, Inglés = AC) / 90-130 Volt

• Altavoz
• Altavoz electrodinámico (bobina de campo)

• Material
• Madera

• de Radiomuseum.org
• Modelo: Majestic 72 Ch= 70 - 7A [Early] - Grigsby-Grunow -Hinds Co.

• Forma
• Consola alta, patas más largas del 50% .

• Anotaciones

• One dial (primary tuning control knob) This set has a push-pull output stage using two 171A power tubes. It is made of walnut with burl walnut front panels and came with a Majestic electric power unit and Majestic dynamic power speaker.
  Model 72 can use the 7P6 or 7P3 power unit. See also Majestic model 72 with chassis 7-B.
  
  This model here shows the loudspeaker below that radio chassis and the B shows the opposite. Maybe one could chose, maybe it is typical for the two versions - we don't know yet. On the speaker unit one can read: Majestic, Power Speaker, Model G1 Serial no. 300012 (not sure, hard to see), for use with model 71, 72, 80 (not sure). The chassis reads: Majestic 7, Electric Receiver Model 70 Serial no. 7A-, Grigsby-Grunow Company, Chicago USA. The cabinet reads: Majestic, Electric Receiver, Model 72, Grigsby-Grunow Company, Chicago USA. There is a hum control adjust for minimum hum in speaker.

  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 C_ag Miller-capacitance, in effect neutralising the triode tendency to oscillate.

• Precio durante el primer año
• 210.25 $

• Ext. procedencia de los datos
• Carlos Vázquez-Hancock

• Mencionado en
• October 27, 1928 Radio Doings magazine advertisement page 30

• Autor
• Modelo creado por Ernst Erb. Ver en "Modificar Ficha" los participantes posteriores.

• Otros modelos

• Donde encontrará 201 modelos, 122 con imágenes y 157 con esquemas.
  Ir al listado general de Grigsby-Grunow (-Hinds) Co. (Majestic pre 1933); Chicago (IL)