Hole positions are indicated by pads with hole dias as shown in drill table.
Pad centres shown as filled in may be due to reproduction faults &does not mean that a hole is not required .
If a pad is to be left undrilled,this will be annotated & listed in the drill table
notes
1.board to be manufactured to (a) double sided to bs 6221 pt5 1982bs 6221 pt5 1982
(b) multi layer to bs 6221 pt6 1982
2.overall copper thickness to be 0.12(0.0048 in)minimum
3.apply photo imageable resist to bs 45b4 pi103 sec103.3(1992).
To sides 1&2 in green resist,over clean copper,resist to be
infra-red cured.
4.finish
(a) copper to be clean finish,selective solder coating (60/40 alloy)
over exposed copper areas only,hot air levelled after resist.
(b) copper to be clean finish,0.05-0.1 microns of 99.9% pure immersion
5.component ident to be printed after solder mask in white ink to bs en 61249 ptb-7 (1997)
6.boards to be marked clearly in ident,to identify the manufacturer and week & year of manufacture.
To be in a position which will not be obstructed by components.
7.blue peelable resist to be added to side 1 after solder mask.
Holes greater than 3.0MM to be spot masked and flush with the board.
8.tolerances
(a)hole dias to be +_0.05,except where stated
(b)holes with relation to copper pattern side 1 to be within 0.2
positional dia,except where stated.
(c)registration of copper side 2 and any intermediate layers to copper side 1 to be within 0.12
(d)all dimensions to be +_0.25 except where stated.
(e)all dimensioned holes to be drilled to dimensions stated,centres shown on artwork for ref,only
(f)min.track width to be 0.3
min.gap to be 0.3