Well, if that is the case ic13 is craped out. Would that cause my synth to play when in PWM mode but not be able to change the PWM shape or speed? --- In PolySix@yahoogroups.com, Johannes Hausensteiner <jo.synth@c...> wrote: > Hi, > > How to determine the pin number of an IC: > > e.g. DIL-8 case: > > > 8 7 6 5 > +|-|-|-|+ > notch: > | > +|-|-|-|+ > 1 2 3 4 > ^ > pin no. one > > I hope this helps ... > > ciscomanvann wrote: > > OK, when I am looking at the IC how do i know which pin is pin 1? I > > found one pin on IC12 that measures +/- 4.7 v but no pin that changes > > on IC13. Hmm > > > > --- In PolySix@yahoogroups.com, Johannes Hausensteiner <jo.synth@c...> > > wrote: > > > >>On KLM-367 check the following: > >>* IC12 (TL072) pin1: must be -5V .. +5V according to PW/PWM poti > >> if not, replace IC12 > >>* IC13 (4558) pin1: must be -5V .. +5V according to PWM SPEED poti > >> if not, replace IC13 > >>* Set PWM SPEED to slowest and check IC1 (4066)/pin9: must change from > >> minus to plus voltage and back (I dont know the exact values; will > >> be at least -3V..+3V) > >> if not, replace IC20 (LM13600) and/or IC15 (4558) > >>* IC1/pin6: must be +5V when WAVEFORM is at PWM position, otherwise 0V. > >> if not, replace IC3 (LM339) > >>* IC1/pin8: must be the same as IC1/pin9 when WAVEFORM is at PWM > >> position, if not replace IC1 (4066). > >>* TP1 (PW/PWM) near IC12: according to service manual "PW/PWM check > >> and adjustment" > >> if not OK, replace IC20 (LM13600) and/or IC15 (4558) > >> > >>I hope this helps, > >> > >>Johannes > >> > >> > >>ciscomanvann wrote: > >> > >>>Nothing happens. It plays, but the width or pwm does not change. I > >>>have a multimeter, how do i check this stuff out? I dont know a whole > >>>lot about ICs. > >>> > >>>--- In PolySix@yahoogroups.com, The Old Crow <oldcrow@o...> wrote: > >>> > >>> > >>>> First thing to do is set VCO to PW and move the width knob from 0 > >>> > >>>to 10 > >>> > >>> > >>>>and back to 0 and listen to see if it changes accordingly. Then > >>> > >>>set it to > >>> > >>> > >>>>10 and change the VCO mode to PWM and move the PWM speed knob from > >>> > >>>0 to 10 > >>> > >>> > >>>>slowly and note if the cyclic modulation is audible. > >>>> > >>>> If nothing is working then I would imagine either IC20 (LM13600) > >>> > >>>needs > >>> > >>> > >>>>replaced, or the analog switch section IC1C died and IC1 needs > >>> > >>>replaced, > >>> > >>> > >>>>or perhaps the control voltages off deMUX IC19 aren't getting there > >>> > >>>and > >>> > >>> > >>>>IC19, IC12 or IC13 is to blame (least likely though). > >>>> > >>>> Use my schematic as it is much easier to read than the old > >>> > >>>service > >>> > >>> > >>>>manual copy. PWM circuit is on the far right, about 2/3 of the way > >>> > >>>down. > >>> > >>> > >>>>It is marked "PWM MG": > >>>> > >>>> > >>> > >>>http://www.oldcrows.net/~oldcrow/synth/korg/polysix/crowlm367/klm367a_ > >>>eagle_schem.gif > >>> > >>> > >>>> Hope this helps, > >>>> > >>>>Crow > >>>>/**/ > >>>> > >>>>On Wed, 31 Dec 2003, ciscomanvann wrote: > >>>> > >>>> > >>>> > >>>>>I know this sounds stupid, but how can i tell if the PWM is > >>> > >>>working? > >>> > >>> > >>>>>If it is not, where do I start looking to fix it? > >>>>>Thanks! > >>> > >>> > >>> > >>>PolySix "Digiest" Page: http://www.acc.umu.se/~amber/Poly6 > >>> > >>>Yahoo! Groups Links > >>> > >>>To visit your group on the web, go to: > >>> http://groups.yahoo.com/group/PolySix/ > >>> > >>>To unsubscribe from this group, send an email to: > >>> PolySix-unsubscribe@yahoogroups.com > >>> > >>>Your use of Yahoo! Groups is subject to: > >>> http://docs.yahoo.com/info/terms/ > >>> > >>> > >>> > >>> > > > > > > > > PolySix "Digiest" Page: http://www.acc.umu.se/~amber/Poly6 > > > > Yahoo! Groups Links > > > > To visit your group on the web, go to: > > http://groups.yahoo.com/group/PolySix/ > > > > To unsubscribe from this group, send an email to: > > PolySix-unsubscribe@yahoogroups.com > > > > Your use of Yahoo! Groups is subject to: > > http://docs.yahoo.com/info/terms/ > > > > > > > >
Message
Re: PWM diagnostics
2004-01-11 by ciscomanvann
Attachments
- No local attachments were found for this message.