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</o:shapelayout></xml><![endif]--></head><body lang=EN-GB link=blue vlink=purple style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal><span style='mso-fareast-language:EN-US'>I did try building this…<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><a href="https://www.lookmumnocomputer.com/projects#/valve-distorting-vca">https://www.lookmumnocomputer.com/projects#/valve-distorting-vca</a><o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>…but the heater ate my -12V rail.<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US>From:</span></b><span lang=EN-US> Synth-diy <synth-diy-bounces@synth-diy.org> <b>On Behalf Of </b>Darren Shorsky via Synth-diy<br><b>Sent:</b> 21 May 2021 20:11<br><b>To:</b> synth-diy <synth-diy@synth-diy.org>; cheater cheater <cheater00social@gmail.com><br><b>Subject:</b> Re: [sdiy] Fwd: [funwithtubes] Vacuum Tube Multitasking - The Erla Superflex<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal><span style='font-size:12.0pt;color:black'>Interesting question...... I'd love to know more.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;color:black'>Hopefully the likes of Eric Barbour come by on occasion.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;color:black'>I think this is the first time I've seen/heard anything about tubes on the list.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;color:black'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;color:black'>Thanx, d.<o:p></o:p></span></p></div><div class=MsoNormal align=center style='text-align:center'><hr size=2 width="98%" align=center></div><div id=divRplyFwdMsg><p class=MsoNormal><b><span style='color:black'>From:</span></b><span style='color:black'> Synth-diy <<a href="mailto:synth-diy-bounces@synth-diy.org">synth-diy-bounces@synth-diy.org</a>> on behalf of cheater cheater via Synth-diy <<a href="mailto:synth-diy@synth-diy.org">synth-diy@synth-diy.org</a>><br><b>Sent:</b> May 21, 2021 5:45 PM<br><b>To:</b> synth-diy <<a href="mailto:synth-diy@synth-diy.org">synth-diy@synth-diy.org</a>><br><b>Subject:</b> [sdiy] Fwd: [funwithtubes] Vacuum Tube Multitasking - The Erla Superflex</span> <o:p></o:p></p><div><p class=MsoNormal> <o:p></o:p></p></div></div><div><div><p class=MsoNormal>I seem to remember a filter design where the audio and the CV were in<br>the same signal, and the CV was very large compared to the audio,<br>essentially a bias, that set the cut-off. Was that the Moog filter<br>perhaps?<br><br>I wonder if this is where the inspiration for such a filter came from.<br><br>Cheers<br><br>---------- Forwarded message ---------<br>From: Mark <<a href="mailto:mark.erdle@gmail.com">mark.erdle@gmail.com</a>><br>Date: Fri, May 21, 2021 at 2:14 PM<br>Subject: [funwithtubes] Vacuum Tube Multitasking - The Erla Superflex<br>To: <<a href="mailto:main@funwithtubes.groups.io">main@funwithtubes.groups.io</a>><br><br><br>In the early 1920s vacuum tubes and the circuitry to operate them were<br>expensive items, so there was a great incentive to get the most bang<br>for the buck out of each tube. As early as 1915, engineers realized<br>that it was possible to have a single triode vacuum tube amplify audio<br>and radio frequency signals at the same time. One of the more<br>successful reflex radio kits was the Erla Superflex of 1924/25, but<br>with the price of vacuum tubes dropping after an RCA patent expired,<br>the reflex design became obsolete by mid 1925 and the TRF and<br>superheterodyne took over the radio market.<br><br>Robert Lozier takes a look at an Erla Superflex in this video:<br><a href="https://youtu.be/Lva1lwUUUpw">https://youtu.be/Lva1lwUUUpw</a><br><br>Mark<br>_._,_._,_<br>________________________________<br>Groups.io Links:<br><br>You receive all messages sent to this group.<br><br>View/Reply Online (#67579) | Reply To Group | Reply To Sender | Mute<br>This Topic | New Topic<br>Your Subscription | Contact Group Owner | Unsubscribe<br>[cheater00social@gmail.com]<br><br>_._,_._,_<br>_______________________________________________<br>Synth-diy mailing list<br><a href="mailto:Synth-diy@synth-diy.org">Synth-diy@synth-diy.org</a><br><a href="http://synth-diy.org/mailman/listinfo/synth-diy">http://synth-diy.org/mailman/listinfo/synth-diy</a><br>Selling or trading? Use <a href="mailto:marketplace@synth-diy.org">marketplace@synth-diy.org</a><o:p></o:p></p></div></div></div></body></html>