From Steve Lenham Sent Fri, Oct 11th 2019, 13:49
From Steve Lenham Sent Fri, Oct 11th 2019, 13:49
You have fitted a 560R resistor (green-blue-black-black) where it should be a 560K (green-blue-black-orange). That will be preventing the transistor which switches in the sustain pot from coming on, so might well have something to do with your problem... Hope this helps! Cheers, Steve L. Benden Sound Technology On 11/10/2019 05:09, W. James Meagher wrote: > Looked over every component and can't locate a mistake made there (all > transistors are where and what they should be). Even decoded all the > resistor color bands to make sure all of those values are correct. > > Build pics: > Freq Central ENV build front <https://imgur.com/99SqcUh> > Freq Central ENV build back <https://imgur.com/VI8SytE> > Freq Central ENV build detail 1 <https://imgur.com/VnqDKJe> > Freq Central ENV build detail 2 <https://imgur.com/GzBrclV> > > > On Thu, Oct 10, 2019 at 11:56 AM James Meagher > <x.xxxxx.xxxxxxx@xxxxx.xxx <mailto:x.xxxxx.xxxxxxx@xxxxx.xxx>> wrote: > > Thanks a lot for the responses. > > I used the BC557 and 547s in the build. I’ll triple check when I get > home that they’re all oriented properly. I’ve also measured both of > the B100K pots and they’re functional. > > I’ll report more, and include detailed build photos when I get home > this afternoon. > > Cheers, > James > > Sent from my iPhone > > On Oct 10, 2019, at 10:51 AM, DJ Maytag <xxxxxxxx@xxxxxxxx.xxx > <mailto:xxxxxxxx@xxxxxxxx.xxx>> wrote: > >> Looking at the board traces, the transistors are directly >> connected to the B100K sustain pot. What transistors did you use? >> The pin out definitely matters, depending on which ones you use. >> The board shows 3x BC547’s and 1x BC557. If you use 3904/3906’s, >> they will be facing backwards compared to the footprint on the >> silkscreen. >> >> http://www.instagram.com/djmaytag >> http://www.soundcloud.com/djmaytag >> https://choon.co/artists/djmaytag/ >> >> ------------------------------------------------------------------------ >> *From:* Quincas Moreira <xxxxxxx@xxxxx.xxx <mailto:xxxxxxx@xxxxx.xxx>> >> *Sent:* Thursday, October 10, 2019 9:52 AM >> *To:* DJ Maytag >> *Cc:* W. James Meagher; AH heaven >> *Subject:* Re: [AH] Frequency Central ENV build help >> I've just recently built the Product, which uses the same ADSR >> circuit and had no issues. I'll see if Rick will share his >> schematics with me and come back with some ideas >> https://youtu.be/QyaoopkA1PU >> >> On Thu, Oct 10, 2019 at 9:31 AM DJ Maytag <xxxxxxxx@xxxxxxxx.xxx >> <mailto:xxxxxxxx@xxxxxxxx.xxx>> wrote: >> >> I’ve built a bunch of these, and they’re dope AF envelopes. >> The “duff 351’s” were going around 3-4 years ago, so aren’t >> much of an issue now. >> >> It’s a clone of the System-100m envelope, so that’s where >> you’re going to find the best schematic. Can you post a link >> to a pic of the build? >> >> http://www.instagram.com/djmaytag >> http://www.soundcloud.com/djmaytag >> https://choon.co/artists/djmaytag/ >> >> ------------------------------------------------------------------------ >> *From:* W. James Meagher <x.xxxxx.xxxxxxx@xxxxx.xxx >> <mailto:x.xxxxx.xxxxxxx@xxxxx.xxx>> >> *Sent:* Wednesday, October 9, 2019 1:44 PM >> *To:* AH heaven >> *Subject:* [AH] Frequency Central ENV build help >> I recently purchased a bunch of Frequency Central boards (DUAL >> XVCA, State 700 VCF and two System X ENVs). The XVCA and State >> 700 VCF builds went fine and work perfectly. >> >> Unfortunately both of the System X Envelopes have a Sustain >> value of 100% no matter where the sus pot is positioned. The >> attack and release work as they should, and the decay can't be >> judged as functioning or not with the sustain always at 100%. >> >> I received Ver. 2B panels for the envelopes and proceeded with >> the build document Version 2 / March 2013. >> (http://www.frequencycentral.co.uk/wp-content/uploads/2013/06/System-X-Envelope-Ver2-Build-Doc.pdf) >> >> The only area where I strayed from the parts as labelled on >> the PBC was replacing the LF351's with TL071's as Rick >> mentioned that "duff" LF351's were making the rounds. I also >> did this on the State 700 VCF build and that went fine. >> >> I've messaged Rick about the issue, and requested a schematic >> or suggestions to help track down the problem, but without >> response. >> >> As this is my first ENV build I'm not familiar enough with the >> circuit to pursue the issue without at least a schematic (or >> helpful hints where to look). If anyone here has any ideas I'm >> all ears and appreciative. >> >> Cheers, >> James >> >> >> >> -- >> QMA >> Quincas Moreira >> Director | QMA >> mobile: 5534988825 <tel:5534988825> >> site: quincasmoreira.com <http://quincasmoreira.com/> >> email: xxxxxxx@xxxxx.xxx <mailto:xxxxxxx@xxxxx.xxx> >> >>