KD

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Hi! This has turned into a ridicoulus state, i wont help you more on this matter, people are focused on how things are said not on whats said, and some goes futher to more or less nitpicking on single sentences ripped out of its context or even single words used. And now some are even start to act smart asses on my behaf. I simply dont have time for that anti bypass capacitor mumbojumbo talk, If you dont want help, OK, so be it then! For those who want to be of more knoweledge and not of lesser knoweledge the rest can be happy to stay at moron state. http://www.sigcon.com/Pubs/news/7_02.htm http://www.sigcon.com/Pubs/edn/cleanpower.htm http://www.edn.com/article/CA454638.html?industryid=2853 http://www.paktron.com/techarticles/hi_speed_circuit/high_speed.html http://www.sigcon.com/Pubs/news/3_7.htm http://www.sigcon.com/Pubs/straight/resonance.htm http://www.altera.com/support/devices/power/integrity/pow-integrity.html http://www.epanorama.net/wwwboard/messages/238.html http://www.sigcon.com/pubsAlpha.htm http://www.ganssle.com/articles.htm http://www.seattlerobotics.org/encoder/jun97/basics.html However there is much things the forum readers are not aware of, once a time (back in 98 or 99) i sent Torsten a mail concerning the lack of bypass capacitors in mail concerning the Core, PSU module, i recall he didnt answer then, so i asumed he had adjusted it since. I also sent him some schematics on solutions wich he implemented and used, that mail he replied to, no one on this forum nows this, even Torsten might have forgot it and i dont mind, no credits was given at time for that either and really i dont give a damn of the credits, because its purpose was of making the MPHB cheaper and better, so before people start to critizise me or other people out of the blue without having decent background info i think its a god idea to chose your words,,,,,,,,,,, twice! Regarding to some requests of some here if i have built a Mbox or two you can figure that out by our self on what i said above.. I certanily dont have any spare time for any KD this, or KD that , if people are happy to use the Torstens design as is,( without knowing possible and future errors), be happy, use it, if you rather be pleased to be of lesser knoweledge, i couldent care less, and if people dont want free help, just say so and i will go away. Reg KD

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Hi! Here is the design proposal for the discussion Torsten and I had over at synt-DIY list regarding to Torstens request of a gate solution for the noisy sid chip! It can be used to anything thats need a gate, volume, envelope, "whatever" funktion, ie OPL3. Torsten, does the MIOS today alow a user to adress one of the software envelope generators to deliver the generated data to a HC595? If not i sugest you will make it possible in future updates! :-) Reg KD

Hi folks and Torsten! As usuall i dont have the time to wade trough the archives so please be patient with my mails if this has been allreday discussed at the forum. I have been going trough all the design schematics and got a bit supriced! Every schematic (exept OPL3) has a major error, the lack of "bypass capacitors"!!!! Long Cabels: Cabels by default contains a small part of inductance, i.e are inductive, curl the cable some turns and you create a Q point of varying magnitude, now run a CLK from , eg the core module to a HC595 a some distance away or so now if Q are high and "in tune" with CLK you can get resonances wich in turn scrambels data, another thing is the impedance matching from core to HC595, if miss matched and rise and fall time are fast enough you will get signal bounching wich will guarenteed scramble data!! In either case by not taking care of this wll limit future development of increase of CLK speeds and improwment of timing can show to be impossble to implement! Thats the background and it needs a adequate cure!! Do this:: One 100nF cap for each device. One 10uF cap (standard elyt) for every five devices. Led boards: For boards who drive LED's a 10-100uF/5V for every board would do, if voltage are pulsating or got rippled by speeded switching increase cap. Analog boards: Boards who deals with analog audio or CV voltages, you really need to place attention to cirquit layout and decoupling if you want high performance. In the case of long cabels between POT and 4051 you can try to use screened cable with one end screen left open. If thats not working place a 6db RC low pass net between every 4051 output and core AN input,(consists of a 100ohm and a 1-100nF cap, R passes signal C shorts AC to ground). However this needs knoweledge of the input capacitance of the PIC18F analog muxer inputs it migh be so that the Ron in 4051 is enough combined with the capacitance of the 18F its self. Socketing: And contrary to whats said ""i wouldent socket the 4051 muxes"" in time and wether sockets will corrode , solder the 4051 they are rugged you wont blow them as long as your input voltage are withing range of the suply voltage. Actually dont socket anything, expect perhaps the MCU! Sadness: Now, dont be sad, a simple solution for the cap requirements is to go out and buy a bunch of 0805 size surface mounted 100nF caps and solder close to +V bridge the other cap end to GND witha fat wire! Hope this design help will enlight you in your course of building!! Reg KD

Hi folks! Im KD, im the name of the KDdac.pdf design, i tought that it could be of help if i spoke directly to the forum regarding the kddac.pdf, i saw that some are concerned about the amount of resistors, you can buy ready matched R2R nets in SIL and SO package, Farnell carries some last time i pooked in the catalog. Reg KD