Based on the Slapback echo stompbox. There were 2 one used a sad1024 the other a mn3005. This is based on the 3005 unit. mod list replaced 3005/1024 with 3007 replaced preset 4047 clock with variable mn3101 added regen loop (2 opamps) converted it to run on split supply another radio sample - weather report 31K http://www.mindspring.com/~vco/cbook/pics/reverb.wav -tg