<DIV id=RTEContent>  <DIV id=RTEContent>  <DIV id=RTEContent>12/13/2005</DIV>  <DIV> </DIV>  <DIV>Question #1: Pulse Width Modulation - I want to build a PWM circuit to use with my home-made VCO's. Two of the schematics that I have for PWMs show a triangle wave input & a modulation input. What type of waveform gets injected into the modulation input ?</DIV>  <DIV> </DIV>  <DIV>Question #2: VCF Resonance & Cutoff Frequency controls - I made my own VCF and want to add Cutoff Freq & Resonance controls. The basic filter design is as follows below. Where in the circuit would I place the Cutoff Freq & Resonance pots ?</DIV>  <DIV> </DIV>  <DIV>Logan</DIV> 
 <DIV>                                                                                            R6</DIV> 
 <DIV>                                                                                    ----/\/\/\/\/\/\--------</DIV> 
 <DIV>                                                                                    |      ----            |</DIV> 
 <DIV>                     R1          R2        R3         R4           R5     |     |      \         |</DIV>  <DIV>Audio In o----/\/\/\/\--.--/\/\/\/\--.--/\/\/\/\--.--/\/\/\/\/\--.--/\/\/\/\--.|.----| --     \       |</DIV>  <DIV>                            |            
 |            |              |                   |   741 \......|......o </DIV>  <DIV>                      C1 ==   C2  ==    C3 ==     C4  ==            |----| +      /         Audio </DIV>  <DIV>                            |            
 |            |              |              \    |       /           Out</DIV>  <DIV>                            ------------------------------------------              /    -------</DIV>  <DIV>                                               
 |                             R7  \</DIV>  <DIV>                                             --------                               /</DIV>  <DIV>                                             
 -----                                |</DIV>  <DIV>                                               ---                                 o</DIV> 
 <DIV>                                                                         Control Voltage Input</DIV>  <DIV>                                                                         from Envelope Generator</DIV>  <DIV> </DIV>  <DIV> </DIV>  <DIV>&nbs!
 p;</DIV> 
 <DIV> </DIV>  <DIV> </DIV>  <DIV> </DIV>  <DIV> </DIV>  <DIV> </DIV>  <DIV> </DIV></DIV></DIV><p>
        
                <hr size=1>Yahoo! Shopping<br> 
Find Great Deals on Holiday Gifts at <a href="http://us.rd.yahoo.com/mail_us/footer/shopping/*http://shopping.yahoo.com/;_ylc=X3oDMTE2bzVzaHJtBF9TAzk1OTQ5NjM2BHNlYwNtYWlsdGFnBHNsawNob2xpZGF5LTA1 
">Yahoo! Shopping</a>