technicalaudio.com/pdf/Electronics_Catalogs/

The files in this directory are very large...

There are individual manufacturer catalog product pages extracted in the following directory

technicalaudio.com/pdf/Electronics_Catalog_Extracts/

in that directory the docs should list up alpha by company name

the doc titles include a couple keywords after company name

there is a code at the end that shows the year and a code for the source catalog

so... if you want transformers search the page for "transformer" so you can jump through and find stuff

enjoy