IDTECH SecureHead SPI User Manual page 54

thick will result in a 0.14+/- 0.03 mm bow. The bumps should by cylindrical and
their crown parallel with the slot wall opposite to the head crown; this will ensure
that when the head is mounted into the rail, its crown will be parallel to the slot
surface and will make good contact with the magnetic stripe on the card. Please
see the below drawing:
13. The length, width and height of rail's slot will affect the stability of reading
performance.
a. The length of the slot to be maximum permitted by dimensional
constraints (if possible it should be 2 times the length of the card).
b. The slot width to be approx. 0.20 mm bigger than the maximum thickness
card that will be swiped through the slot.
c. The height of the slot should be as big as the dimensional constraints
allow but shall not extend over the embossing area of the card unless
there is a provision (recess) in the rail wall design to allow for such
embossing.
14. The window in the rail wall through which the head protrudes into the slot should
be big enough to allow free movement of the head.
15. The clearance between the head and the wall of the rail window depends on the amount of
head travel and on the head protrusion. (The distance from the crown of the head to the
surface of the spring)
16. For a standard rail with 1.03
protrusion minimum 1.25 mm clearance must be allowed on all sides of the head.
17. Note: guideline does not apply when low profile heads are used. The window must allow
clearance for the portion of the spring welded to the magnetic head as shown in figure below.
ID TECH SecureHead SPI with TMIV User Manual
mm wide slot and a standard ID Tech head with 3.50 head
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