On 15/11/2014 11:52, Nick wrote:
I'm trying to use a couple of 'vintage' Mullard ferrite toroids. They
are marked FX1585/D4 and appear to date from c.1960.

Google does not know.

Does anyone have the data please? I believe it may be in the Mullard
Technical Handbook Volume 6 Part 2.

Please have a look on your bookshelves.

nick



I have in my library
MULLARD 3P2 FERROXCUBE/PXE/MAGNETS 1971
MULLARD 3P2 MAG.MATERIALS,PIEZO
MULLARD 3P2 MAG.MATERIALS,PIEZO 1972
MULLARD 3P3 INDUCTOR CORES 1978
MULLARD 3P4 RM INDUCTOR CORES 1972

what data are you after?

While at it does anyone know if the likes of the British Library or the
library at the Wroughton storage facility of the Science Museum have
these sorts of books available for consultation, retained for posterity?
I'm aware the Southampton University library unceremoniously dumped all
their electronic data books,from their stack, into a skip without
checking for any other holdings in the UK.