brltty and blt18

[Paul Migliorelli (+1 3 0 3 5 4 3 2 3 1 1)]

Hi all.  Am trying to set up a blt 18, but am running into trouble finding 
out how and which contraction table implementation.  8 dot mode is turned 
off in the status menu of the b l.  The b l revision is July 1 of 2001 and 
it is a 640, older model with older serial ports.  The powerbraille at the 
office came up without a hitch, but this home set up is a challenge.  
Thanks much.