30-11-2023, 08:43 PM
(This post was last modified: 30-11-2023, 08:45 PM by Geordie McBoyne.)
The title of this essay describes the development of television receivers between 1936 to 1939.
The author was C. Edwards who was employed by Pye Limited.
The work consists of all aspects of receiver design including the 1939 models 9C and 12C.
The text includes an appraisal of the various RF pentodes employed in TV sets starting with the Mazda AC/SP3 through to the EF50.
The attachment shows the properties of various RF pentodes working at 45Mc/s. The clear winner is the EF50.
Those early pentodes were pretty hopeless at 45Mc/s. Despite it's high gm figure the AC/SP3 was little better than the M.O. MSP4.
Missing from the table is the Mullard TSP4, the Mazda SP41 and the M.O. KTZ41.
The KTZ41 had a very high gm of 12mA/V. It was used in pre-war GEC TV receivers as an RF and IF amplifier. As an IF amplifier in EMI sets.
https://frank.pocnet.net/sheets/179/k/KTZ41.pdf
M.O. Z62: https://www.radiomuseum.org/tubes/tube_z62.html
Geordie McBoyne.
The author was C. Edwards who was employed by Pye Limited.
The work consists of all aspects of receiver design including the 1939 models 9C and 12C.
The text includes an appraisal of the various RF pentodes employed in TV sets starting with the Mazda AC/SP3 through to the EF50.
The attachment shows the properties of various RF pentodes working at 45Mc/s. The clear winner is the EF50.
Those early pentodes were pretty hopeless at 45Mc/s. Despite it's high gm figure the AC/SP3 was little better than the M.O. MSP4.
Missing from the table is the Mullard TSP4, the Mazda SP41 and the M.O. KTZ41.
The KTZ41 had a very high gm of 12mA/V. It was used in pre-war GEC TV receivers as an RF and IF amplifier. As an IF amplifier in EMI sets.
https://frank.pocnet.net/sheets/179/k/KTZ41.pdf
M.O. Z62: https://www.radiomuseum.org/tubes/tube_z62.html
Geordie McBoyne.