18-01-2016, 08:47 PM
(This post was last modified: 18-01-2016, 08:54 PM by Geordie McBoyne.)
That's an useful website. The insides of the smokers cabinet were discarded sometime in the early 1930s. Judging from the cutouts in the cabinet floor and shelf some other type of radio had been installed for a while. The cabinet floor was recently replaced and the shelf repaired. In due course the RB12 was replaced by a another Marconi, a model 272.
The early superhet that looks like this one: http://www.radiomuseum.org/r/marconi_272.html
The coils will resemble the pancake types in the pictured model 32 although I suspect those coils are recent reproductions. According to the Brown Brothers advertisement for the VB4 the set covers 300 to 3000 meters in four stages. "Tuning is by means of the spade system and the spades are of such a shape that straight line tuning is obtained.
The wave-length range is covered without the use of interchangeable coils or range blocks by means of four coils and a four position switch which connects the coils in series and in parallel, so that the set is self contained for the receiving broadcasting as well as the Eiffel Tower time signals and other longwave transmissions." "For the lowest wavelengths the two smaller coils are used in parallel. The next stage is obtained by these coils in series"
The higher wavelengths are covered by separate coils used in a similar manner, parallel and series.
The tuning assemblies are about six inches diameter and no more than one inch deep.
It's not going to be an easy recreation job.
Geordie McBoyne.
The early superhet that looks like this one: http://www.radiomuseum.org/r/marconi_272.html
The coils will resemble the pancake types in the pictured model 32 although I suspect those coils are recent reproductions. According to the Brown Brothers advertisement for the VB4 the set covers 300 to 3000 meters in four stages. "Tuning is by means of the spade system and the spades are of such a shape that straight line tuning is obtained.
The wave-length range is covered without the use of interchangeable coils or range blocks by means of four coils and a four position switch which connects the coils in series and in parallel, so that the set is self contained for the receiving broadcasting as well as the Eiffel Tower time signals and other longwave transmissions." "For the lowest wavelengths the two smaller coils are used in parallel. The next stage is obtained by these coils in series"
The higher wavelengths are covered by separate coils used in a similar manner, parallel and series.
The tuning assemblies are about six inches diameter and no more than one inch deep.
It's not going to be an easy recreation job.
Geordie McBoyne.
