| Digest Nr | Subject and Author |
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| 2020.03.17.01 | Wurlitzer 150 Organs With Duplex Roll System, from Fred Dahlinger |
| 2019.02.17.03 | Seek 85-note Wurlitzer Duplex Spool Frame, from Tom DeLay |
| 2018.03.12.03 | Music Roll Cores For Wurlitzer Duplex Frame, from Julie Porter |
| 2018.03.10.01 | Music Roll Cores For Wurlitzer Duplex Frame, from Don Teach |
| 2018.03.08.02 | Seek Music Roll Cores For Wurlitzer Duplex Frame, from John Grant |
| 2018.03.02.02 | Seek Music Roll Cores For Wurlitzer Duplex Frame, from Steve Grattan |
| 2017.06.25.05 | Seek Wurlitzer 165 Duplex Spool Frames, from Lawrence McGowan |
| 2017.06.18.05 | FS: Wurlitzer Duplex Roll Frame, from John Grant |
| 2016.10.24.01 | Coinola Duplex Midget Has Two Roll Frames, from Don Teach |
| 2015.11.03.05 | Wurlitzer Duplex Tracker Bar Roll Frame DVD, from Michael Jones |
| 2015.10.31.02 | Wurlitzer Duplex Roll Mechanism Explained, from Matthew Caulfield |
| 2015.02.08.01 | Coinola Duplex Midget Nickelodeon, from Bruce Miller |
| 2012.09.04.01 | Double ( Duplex) Roll Frames on Carousel Organs, from William Edgerton |
| 2011.06.08.07 | WIDI Duplex Wireless MIDI Interface Utilities, from Spencer Chase |
| 2010.01.21.05 | Adjusting the Wurlitzer Duplex Roll Frame, from Barry Casper |
| 2009.11.30.10 | Seek Wurlitzer Duplex Spool Frames, from Don Teach |
| 2009.05.03.07 | Trade Wurlitzer Duplex Roll Frame, from John Haass |
| 2006.02.23.14 | Seek Bellcrank for Wurlitzer Duplex Frame, from Doug Hershberger |
| 2004.11.11.02 | Seek Wurlitzer Duplex Roll System Publication, from Bob Stewart |
| 2004.02.19.10 | Lauter-Humana " Duplex Pumper" & Silly Patents, from Mark Kinsler |
| 2004.02.14.02 | Lauter-Humana " Duplex Pumper", from John A. Tuttle |
| 2003.07.15.04 | Parts for Wurlitzer Duplex Roll System, from Julie Porter |
| 2003.07.14.05 | Parts for Wurlitzer Duplex Roll System, from Matthew Caulfield |
| 2003.07.13.01 | Seek Parts for Wurlitzer Duplex Roll System, from Gordon Forcier |
| 2001.02.28.10 | Duplex Roll Player for Organ, from Bob Loesch |
| 1999.07.17.02 | Wurlitzer Duplex Roll Frame, from Craig Brougher |
| 1999.07.16.09 | Wurlitzer Duplex Roll Frame, from John Rutoskey |
| 1999.07.16.08 | Wurlitzer Duplex Roll Frame, from Don Teach |
| 1999.07.16.07 | Wurlitzer Duplex Roll Frame, from Matthew Caulfield |
| 1999.07.15.05 | Wurlitzer Duplex Roll Frame, from Dave Clark |
| 1997.12.11.06 | Vertically Stacked Duplex Spool Frame, from Marc Elbasani |
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