Did any company have a convention of putting different colour sleeving on axial diodes instead of coloured bands ? Doesn't matter in the present case as any old 1N4005 etc would do , but for future reference. All over black enamelled or black glass with no markings and blue sleeve on anode lead and red on cathode lead, so not going with red to positive for forward current transfer. Size etc oes not agree with 1N602 , 1N206 , 602, 206 not found,
1N1206,1N1602, 1N2206 not found, 1N2602-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on
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