Meljean, I'm thinking the 803A has built-in cams. I'm thinking that it is very close to Deluxe Zig Zag #25 (KAB-M) at
http://www.sewusa.com/Sewing_Machine...g_Machines.htm The ZZ stitches look close, except for having additional steps. Also the feed dog drop is on the stitch length knob, instead of on the bed.
I couldn't find one similar to the the 803 that has the door in the front of the arm for cams to be placed in.
Janey - Neat people never make the exciting discoveries I do.
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