ch%maths.tcd.ie@cunyvm.cuny.edu (Charles Bryant) (08/06/89)
In article <telecom-v09i0273m08@vector.dallas.tx.us> mcvax!cgch!wtho@uunet.uu. net (Tom Hofmann) writes: >An other apparently not standardized feature is the keypad layout of >push-button phones. In Ireland one layout is *required* if equipment is to be approved (TTA1 P.80 part b) The arrangement of push buttons in the equipment shall be as shown in Table 1 in the case of manual signalling: 1209 1336 1477 1633 697 1 2 3 A 770 4 5 6 B 852 7 8 9 C 941 * 0 # D The output frequencies shall be maintained within plus-or-minus 1.5% of their nominal value. This tolerance shall also include the effect of different line impedances offered to the sender. I have never seen a phone which has the ABCD column, and I expect that those tones are not used. There is no extra charge for the ability to DTMF dial on a line, but it is not yet available on all lines. -- Charles Bryant. (ch@dce.ie) Working at Datacode Electronics Ltd. (Modem manufacturers)