Align = Alignment instructions for the 400 and 500
        range tuners and the stereo decoders.

Components = List of component values and types
             by part number. The circuit diagrams for
             the 400 and 500 ranges show components
             simply by part number so this list is
             required to convert these into values
             and types.

SpecSheet = Basic list of specs for 400 range.

ServiceData  = Booklet (green cover) given to dealers
               etc. Contains the same list of components
               and data as in "Align" and "Components"
               but in a better-printed form.
               Provides data for 400 and 500 units.

521Install  =  Installation and Operating manual provided
               with a 521 for the owner.

525/526Install = Installation and Operating manual for
               the 525 and 526. One of the copies scanned
               here (JB) has a red oversticker on page4.
               The other copy (BAH) has no sticker,
               but has underlining and editing notes
               in green. There are therefore multiple
               scans of this page to show all details.

TechAdvice  =  Advice note explaining (with a flowchart
               and diagrams) how to deal with hum, 
               interference, and fit attenuators for
               use with tape sources high or low level.
               Note was in the form of an A4 sheet, printed
               on each side, then folded in two to make
               a leaflet.