kokoon Posted October 19, 2005 Report Posted October 19, 2005 i made this last night and i can't believe how much difference it makes!i haven't measured the SNR yet but on 8580 i virtually can't hear any noise at all!big up to you TK!!! this synth really is taking it's shape. Quote
mesak Posted October 20, 2005 Report Posted October 20, 2005 well, i have the normal PSU and it sounds like this: http://www.mrvelcrofastener.com/sid/humina.wav - i think it's terrible, can it be just because the PSU isn't the "optimized" type? the hum clearlty changes when switchin the filter on/off to oscillators, doesn't get more silent or loud but just different.but if i make the optimised PSU do i need to make changes to CORE or SID module? cheers Quote
kokoon Posted October 20, 2005 Author Report Posted October 20, 2005 it's all written in the pdf that's linked on the ucapps.de sid module page.the difference is HUGE. no background hum at all! the sid quirks still remain (hanging notes, funnny filter switching behavior you mentioned) but still - it's absolutely usable now! especially the 8580.you *absolutely* have to do this mod! Quote
mesak Posted October 21, 2005 Report Posted October 21, 2005 oh yes, it says: "(3) the 7805 regulators of the core modules have been removed. The Input/Output lineof this IC has been shortened so that C5 of the core module (ca. 1000 uF is ok)is directly connected to the +5V input"this is also shown in the diagram.but what about the 7809? "(2) a 7809 removes the AC part of the SID module supply voltage. Without thisadditional voltage regulator you may hear a 50/60 Hz humming sound at the SID output"the SID module will remain the same? atleast there's no changes in the diagram....cheers Quote
moebius Posted October 21, 2005 Report Posted October 21, 2005 but what about the 7809? "(2) a 7809 removes the AC part of the SID module supply voltage. Without thisadditional voltage regulator you may hear a 50/60 Hz humming sound at the SID output"the SID module will remain the same? atleast there's no changes in the diagram....Yes, the SID modules remain the same. (Well.. unused audio inputs are shown as grounded and the last SID module has a cap added between +5VDC and GND contacts)The schematic shows 9VAC from the C64 powersupply first rectified to DC (by B40C800), filtered by additional caps and that 7809 regulator has it's "common" pin connected to +5VDC so the output referenced to ground is 14VDC. And this is then regulated down by SID modules.Bye, Moebiusp.s. Soo nice to see you here, Mr. Velcro ;) Quote
kokoon Posted October 21, 2005 Author Report Posted October 21, 2005 i'm a total n00b, this midibox sid is my first soldering ever but i already managed to almost finish it. and i got the optimized psu right in the first try :)i just did everything exactly like it says in that pdf. though it took me a hour or so to place it all on the breadbord (or whatever it's called - the plain board with a grid of holes and copper rings/circles around them) - not on the stripboard. Quote
mesak Posted December 14, 2005 Report Posted December 14, 2005 okay, i have had too big gap from where i didn't have time anymore to build the SIDbox... but now i want to get it finished finally! :Dchanging to optimized PSU seems easy to do, but i want to make sure couple of things (avoiding more mistakes):J1 of core module is unconnected with optimized PSU, that's that?in optimized PSU there's no GROUND as was in the original PSU - what about audio out? it should still have ground connected too should it? is there any options for the B40C800 in case i can't find the component?many thanks! Quote
moebius Posted December 14, 2005 Report Posted December 14, 2005 J1 of core module is unconnected with optimized PSU, that's that?Yes. You connect +5VDC to the core/SID J2. (mind the polarity) - leave the regulator out from the core... ect.in optimized PSU there's no GROUND as was in the original PSU - what about audio out? it should still have ground connected too should it? The Ground is there, but it's just not marked as ground but Vs. And yes, audio out needs Ground connection.is there any options for the B40C800 in case i can't find the component?I'd say any bridge rectifier should work. Or 4 x 1N400* series diodes (1N4001<->1N4007)Bye, Moebius Quote
mesak Posted December 19, 2005 Report Posted December 19, 2005 I'd say any bridge rectifier should work. Or 4 x 1N400* series diodes (1N4001<->1N4007)Bye, Moebiusi found these: B40C1500R, 2KBP08 or MBS10... does someone have any opinions of which would be most suitable?cheers Quote
moebius Posted December 19, 2005 Report Posted December 19, 2005 Well,I haven't made any comparisons - but B40C1500R is the same series as B40C800 and you can directly tell it's ok: rated 40Volts and 1500mA versus the original 40V/800mA..M Quote
crazylarry Posted December 20, 2005 Report Posted December 20, 2005 so what all extra do you need to buy? and where do you solder the cap on #3 of the pdf? 5v and what else?L- Quote
raphael Posted December 20, 2005 Report Posted December 20, 2005 and where do you solder the cap on #3 of the pdf? 5v and what else?Just solder it like on the unmodified (original) core module! There is no difference beside the bridging of pins 1 and 3 of the 7805 (leave the 7805 out). so what all extra do you need to buy? All parts on the left side:1 x B40C800 rectifier2 x 2200uF/16V electolytic cap1 x 100nF cap1 x 330nF cap1 x 78091 x 220 Ohm resistorReuse the swith and power plug from the C64!Raphael Quote
raphael Posted December 20, 2005 Report Posted December 20, 2005 Just solder it like on the unmodified (original) core module! There is no difference beside the bridging of pins 1 and 3 of the 7805 (leave the 7805 out). All parts on the left side:1 x B40C800 rectifier2 x 2200uF/16V electolytic cap1 x 100nF cap1 x 330nF cap1 x 78091 x 220 Ohm resistor (only if you want to use a LED as power indicator)Reuse the swith and power plug from the C64!Raphael Quote
mesak Posted December 21, 2005 Report Posted December 21, 2005 Just solder it like on the unmodified (original) core module! There is no difference beside the bridging of pins 1 and 3 of the 7805 (leave the 7805 out). All parts on the left side:1 x B40C800 rectifier2 x 2200uF/16V electolytic cap1 x 100nF cap1 x 330nF cap1 x 78091 x 220 Ohm resistorReuse the swith and power plug from the C64!Raphaelplus 1 x 2200/25uF isn't it? (between B40C800 and 330nF between the PDF)? Quote
thefRont Posted December 21, 2005 Report Posted December 21, 2005 plus 1 x 2200/25uF isn't it? (between B40C800 and 330nF between the PDF)?yes, that one was missing in raphaels partlist Quote
moebius Posted December 21, 2005 Report Posted December 21, 2005 Whuzz is this: "2200/25uF"? I can see it on the schematics - Some strange shit my electronics shop couldn't deliver? :)Could it be 2200uF/25V? And as raphael simplified it: 2200uF/16V is enough.M Quote
mesak Posted December 21, 2005 Report Posted December 21, 2005 Could it be 2200uF/25V? And as raphael simplified it: 2200uF/16V is enough.ah, ok... i thought that it was 2x 2200uF/16V for you add one of those at the end of SID chain, vs & vdcheers Quote
mesak Posted December 22, 2005 Report Posted December 22, 2005 DONE! and it sounds absolutely beautiful :D Quote
experimental Posted December 29, 2005 Report Posted December 29, 2005 DONE! and it sounds absolutely beautiful :DCould you post some photo's of your work! That would be great! Quote
mesak Posted January 1, 2006 Report Posted January 1, 2006 Could you post some photo's of your work! That would be great!sure! i'll put up some more decent photos soon. here's one from few weeks back in testing phase.. it's built inside a suitcase for packing it quick and taking on the road! :Dt Quote
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