Here are the Echoplex Schematic changes from Rev A1 to Rev B schematic, which was released 10/17/94:



Page 7:  Add R96 (1.40K 1% metal film .25W thru Resistor) in series with 

          C18. C18 and R96 should then be in parallel with R11. For Layout

          R96 should be placed between C18 and R12.



Page 7:  Add R97 (1.40K 1% metal film .25W thru Resistor) in series with 

          C22. C22 and R97 should then be in parallel with R24. For Layout

          R97 should be placed between R23 and R24.



Page 7:  Remove C34



Page 7:  Change C28 from 680pf ceramic cap to 22pf Ceramic Cap (no layout 

          change needed.)



Page 7:  Disconnect R13 from ground. Reconnect same pin of R13 to -12V.



Page 8:  Add C127 (4.7uF Electrolytic Cap 50V 20% Radial thru 5x11mm 

          .1LS .02LD) in series before R6. (between U1/pin1 and R6.) The 

          positive pin should be on the U1 side. For Layout, C127 should 

          be placed to the left of C8.

