Hi Stuadh > As to using different power boards, I'm assuming that this refers > to separate distribution boards, and not different PSUs? I can easily install another > dist board for the "noisy" modules. Actually that should solve the problem: 1 PSU to power the distrib. boards for "clean" modules and another 1 for the "dirty" ones. Just crossing my mind what your cap querry earlier might refered to: on the Oakley distr. board 2 separate ground rails are connected through a 470nF cap but this is of no help with the Doepfer board since here all 6 ground pins are already connected on the board's pcb. Regards, Ingo > Stuadh > > --- In Doepfer_a100@yahoogroups.com, "Andrew Ison" <andrew.ison@n...> > wrote: > > Hows about live components touching the earthed rack itself? > > ----- Original Message ----- > > From: stuadh > > To: Doepfer_a100@yahoogroups.com > > Sent: Friday, December 03, 2004 11:02 AM > > Subject: [Doepfer_a100] Re: Power Source interference > > > > > > > > In my case, I can't really contact Doepfer direct as I'm using a > mix > > of A Sys, Doepfer and homemade modules with a 6U A Sys case and a > 6U > > homemade case Power-one PSU). That said, the trouble started > before > > I added any of the homemade stuff and I added the a-146 LFO to > the A > > Sys case. That was the clincher. I agree that the LED may not > be > > causing the problems, but in my case, the modulation is clearly > co- > > incident with the the LEDs - speed up the LFO/ADSR or whatever, > and > > the modulation speeds up, too. I'm also well within my Ampage > limit > > (by about 3 Amps) > > While I may be wrong, I believe that my cases are correctly > > grounded. I've tested the voltages of the PSUs and they check > out. > > > > I was particularly interested in a thread when I first raised > this > > problem here which Julian and others helped with. Then, it was > > mentioned that adding large capacitors across the power rails > might > > help. My questions are: > > > > what sort of value is recommended? > > Does a cap have to be added at the end of each distribution > board, or > > is one pair in a system enough? > > What type of cap is recommended? > > Does it work? > > > > Cheers > > > > Stuadh > > > > --- In Doepfer_a100@yahoogroups.com, Bakis Sirros > > <synth_freak_2000@y...> wrote: > > > btw, it is really wierd: > > > i have a modular with 18 PSU's and i have never > > > noticed any interference in the audio outputs. > > > are you sure that all the 6U cases are properly > > > grounded? > > > but, of course, you should contact Roland Mayer > > > direct. > > > his email: technik@d... > > > bakis. > > > > > > > > > > > > > > > --- selfoscillate <synaptic_music@y...> wrote: > > > > > > > > > > > > > > > hello richard, > > > > > > > > i'd love to help you, but i can't. > > > > i'm a nut when it comes to electrical things. > > > > maybe you should email the technical > > > > stuff at doepfer directly. > > > > > > > > best wishes > > > > > > > > ingo > > > > > > > > > > > > > > > > --- In Doepfer_a100@yahoogroups.com, "trebcavxx" > > > > <richardbarton@c...> > > > > wrote: > > > > > > > > > > You've highlighted a condition that's been present > > > > in my own 75- > > > > > module synth almost from the word GO - pulsating > > > > modulation in the > > > > > sound output. It occurs to a greater or lesser > > > > degree in virtually > > > > > ALL patches (I have 11 VCOs) - and takesd the form > > > > of a cyclic > > > > > variation in amplitude - usually giving the sound > > > > a "woo- > > > > > woo.......woo-woo........woo-woo" character rather > > > > than a straight > > > > > tremolo effect. As I say, this has happened from > > > > the humble > > > > > beginnings of a single VCO setup. I now have 5 > > > > seperate power > > > > > supplies in the cabinet. I'm a bit doubtful that > > > > LEDs are causing > > > > it > > > > > in my case, but would anyone have a cure for > > > > either of our > > > > problems ? > > > > > I notice the previous mailing has been pretty well > > > > ignored. > > > > > Richard > > > > > > > > > > --- In Doepfer_a100@yahoogroups.com, "stuadh" > > > > <stuadh@h...> wrote: > > > > > > > > > > > > Hi, > > > > > > > > > > > > I've been reading up on interference caused by > > > > LEDs on the > > > > > > power bus in the archives, a problem that I'm > > > > having in my > > > > > > homemade and commercial cases. I've minimised > > > > the problem > > > > > > by strategically placing the offending modules, > > > > but there was > > > > > > some discussion about including large capacitors > > > > between the > > > > > > power rails to help stop this problem occuring > > > > in the first place. > > > > > > > > > > > > Has anyone done this, and was it successful? > > > > > > > > > > > > What constitutes a "large capacitor" and what > > > > type. Does the > > > > > > polarity make a difference? > > > > > > > > > > > > Yours Aye > > > > > > > > > > > > Stuadh > > > > > > > > > > > > > > > > > > > > > > > > > ===== > > > Bakis Siros > > > Parallel Worlds / Polariton > > > Athens-Greece > > > [Doepfer_a100] group owner > > > http://www.shimarecords.co.uk > > > http://www.ward12.com > > > > > > > > > > > > __________________________________ > > > Do you Yahoo!? > > > Yahoo! Mail - now with 250MB free storage. Learn more. > > > http://info.mail.yahoo.com/mail_250 > > > > > > > > > > Yahoo! Groups Sponsor > > ADVERTISEMENT > > > > > > > > > > > > ----------------------------------------------------------------- --- > ---------- > > Yahoo! Groups Links > > > > a.. To visit your group on the web, go to: > > http://groups.yahoo.com/group/Doepfer_a100/ > > > > b.. To unsubscribe from this group, send an email to: > > Doepfer_a100-unsubscribe@yahoogroups.com > > > > c.. Your use of Yahoo! Groups is subject to the Yahoo! Terms of > Service. > > > > > > > > [Non-text portions of this message have been removed]
Message
Re: Power Source interference
2004-12-08 by ilanode