Two years ago I built a "caller" system that uses a Sony voice recorder. Have been using it for IMAC contest and practice. I have a recorder attached with velcro to my transmitter tray. The recorder playback is activated by a push button by my left pinkey. There are four folders on the recorder so I use one for R to L, one for L to R and use aznother one for recording the Unknown manuvers at a contest. I am currently working on a magazine construction article which should be published in 2011.