fussylizard Posted May 27, 2009 Author Report Share Posted May 27, 2009 Hah me too! In fact, I stopped doing music altogether so I could concentrate on my synth. After I finish the MB-6582, I've gotta then upgrade a few parts of my "studio" but hope to get back to music soon. Using the LEDs on my Virus is indeed a good idea! I was hoping to get the LEDs today, but, alas, they were not in the mail. Oh well.And yeah, LED rings are hot. Maybe on my next MidiBox project (probably will do a MB64 type of thing at some point).Already sliding down the slippery slope it seems... :-) Quote Link to comment Share on other sites More sharing options...
m00dawg Posted May 27, 2009 Report Share Posted May 27, 2009 Well, at least I pushed off my smart holiday lights project (for now :). The MB64 project was mostly for a mixer I could use for both Tracktor and for at home but is kinda a side project anyway. So I'm hoping to get back into music as soon as the MB-6582 is done. The MB64 will have to take a backseat to that. Quote Link to comment Share on other sites More sharing options...
Mu-Tron Posted May 27, 2009 Report Share Posted May 27, 2009 A quick related question: How is the clearance between the 25mm screws on the panel and the base PCB underneath? I receive my panel tomorrow, and so will be doing my JB Welding, but a quick test of putting the screws in the mount holes has me worried that the screws are somewhat long (despite being the 25mm specified), as they're pretty close to where the baseboard should be at the front. Quote Link to comment Share on other sites More sharing options...
m00dawg Posted May 27, 2009 Report Share Posted May 27, 2009 You mean the corner screws? Yes, they are a bit long, but I haven't run into any problems. I debated on trimming them once all was said and done but it doesn't look like that will be necessary for me. Quote Link to comment Share on other sites More sharing options...
fussylizard Posted May 27, 2009 Author Report Share Posted May 27, 2009 I haven't had any problems with the corner screws being too long.FWIW Be generous on the JB-Weld but make sure the panel can sit flush on the top of the case (mine wasn't flush, so I think the continuous pressure may have contributed to the screws becoming loose on my panel). I need to post the pics of what I ended up doing, but I sawed off the little corner tabs entirely and used large washers to hold the front panel onto the top part of the case. It worked pretty well. Quote Link to comment Share on other sites More sharing options...
fussylizard Posted May 31, 2009 Author Report Share Posted May 31, 2009 Finally, here's some pics of how I finally ending up attaching my front panel to my case.The first pic shows (for reference) how much JB-Weld I used for the first try which didn't work out well as I noted in an earlier post.The second pic shows how much JB-Weld I used for the second try. I also used a razor blade to scratch up the back corners of the panel. The steel blade actually allowed me to cut into the soft aluminum panel and make little bits of aluminum stick up. I tried sandpaper but it just wasn't that rough. Anyway, I used a *lot* of JB-Weld the second time......which leads us to the third pic showing that the panel would not sit flush on the top part of the case due to the "cone" of JB-Weld. Wilba recommended "countersinking" the little corner mount holes, but with all the JB-Weld I used I wasn't sure there would be any plastic remaining. So I opted for a different approach, as will be shown in my next post.NB- Just to eliminate any confusion, note that the second picture was taken when I had to fix my completed control surface after the corner screws came loose. This is why the front panel is already built in this picture. If you're building a control surface you should follow Wilba's instructions and glue the bolts *before* soldering the control surface PCB, etc.frontpanel-corners-firsttry-IMG_3760.JPGfrontpanel-corners-secondtry-IMG_3846.JPGfrontpanel-corners-secondtry-notflush-IMG_3849.JPGfrontpanel-corners-firsttry-IMG_3760.JPGfrontpanel-corners-secondtry-IMG_3846.JPGfrontpanel-corners-secondtry-notflush-IMG_3849.JPG Quote Link to comment Share on other sites More sharing options...
fussylizard Posted May 31, 2009 Author Report Share Posted May 31, 2009 First pic - I ended up cutting off the corner mounting tabs with a hobby saw. Super quick and easy. The cones of JB-Weld still slightly overlapped the edges of the ledge on the top of the case where the panel is supposed to rest, so I used some small files to file down the ledge until the panel would sit flush.The purpose (as far as I can tell) of the corner screws is to hold the panel onto the top of the case and prevent the front panel from being lifted up off the case. The edges of the front panel should be sitting flush on the inside ledge of the case. If the panel is not flush against the ledge due to JB-Weld, there can be pressure on some of the corner screws which is what I believe was the main cause of my screws coming loose (literally, not figuratively!). FWIW the spacers glued to the front panel and screwed into the CS PCB hold the PCB against the front panel, not the corner screws. Since there are so many spacers, you probably don't need to go crazy on the JB-Weld for the spacers.Anyway, to hold the front panel onto the top of the case I just used a washer large enough to overlap the corner of the case (actually I had to use two washers, one to overlap the case and another smaller one to cover the main washer hole to prevent the nuts from slipping through the first washer central hole). I then used one nut to hold the washer in place, followed by a lock washer and a second nut. I would not recommend using a single nut since by doing that you are pulling the bolt away from the back side of the case, which may pull the JB-Weld off. By using two nuts tightened together, there is no pressure against the corner screw except if you try to lift off the front panel. The lock washer of course prevents the nuts from becoming loose.So in the second pic you can see from right to left:- the large washer- the small washer- the first nut- the lock washer- the second nut- the PC boardBTW I had to find a smaller washer for the corner near the SID R light (upper right corner of the CS) to avoid contact with the washer, but really it shouldn't matter if the washer only touches one lead of the LED. Also, I may JB-Weld the washers in place so they won't move around during transport, but I got a small amount of pressure on the washers to keep them in place and they seem reasonably solid so far.Overall I'm fairly pleased with the mounting and would probably do it this way again if I make a second MB-6582...frontpanel-removed-corners-IMG_3851.JPGfrontpanel-nocorners-nuts-IMG_3858.JPGfrontpanel-removed-corners-IMG_3851.JPGfrontpanel-nocorners-nuts-IMG_3858.JPG Quote Link to comment Share on other sites More sharing options...
fussylizard Posted June 7, 2009 Author Report Share Posted June 7, 2009 Here's a couple more pics.1) Here's another view of how I attached the front panel to the case after sawing out the corners2) I glued a plexiglass window to the back side of the front panel. Not sure how well it will hold up to pressure, but it looks great! I had a couple of spacers come unglued, so I reinforced them. All the JB Weld doesn't look pretty, but looks don't matter on the back side and I wanted to ensure they stayed put.I also compared feedback pots, a 500k audio taper vs. a 100k linear taper. I think I prefer the 100k linear taper since it has a more useful range, whereas the audio taper doesn't really do much until the last eighth turn or so. Since the pots I ordered were too large, I'll have to hunt down some new, smaller ones.frontpanel-nocorners-nuts-IMG_3865.JPGfrontpanel-plexiglass-IMG_3880.JPGfrontpanel-nocorners-nuts-IMG_3865.JPGfrontpanel-plexiglass-IMG_3880.JPG Quote Link to comment Share on other sites More sharing options...
fussylizard Posted June 7, 2009 Author Report Share Posted June 7, 2009 BTW I tried out the screws I bought to secure the base PCB into the case (see this thread: http://www.midibox.org/forum/index.php/topic,13573.msg117148.html#msg117148).I also cut ventilation slits in the side of my case (woohoo!) as documented here: http://www.midibox.org/forum/index.php/topic,13502.msg117149.html#msg117149.Finally, I located some heatsinks for 28 pin DIP packages. Not sure if they'll work with the "wide" package used by the SIDs, but if they fit okay I'll post additional info on them.Basically all I have left is to get and install the final knobs, and order/install the feedback pots. Quote Link to comment Share on other sites More sharing options...
Filch Posted June 16, 2009 Report Share Posted June 16, 2009 I used standard IDC cable since that's what I had, and I couldn't find the other stuff on Mouser (I'm sure it's there, but I just couldn't find it). The standard IDC cable seems fine to me. I found some, but you can only get it in a 100' roll for $54Mouser Part #82-28-6081I'm still trying to locate a cheaper source or smaller quantity**EDIT**I just found this. .100 , 6 inches long, 9 wire. This is near perfect. I have to buy a minimum of 60 of these though. So I will have a ton of extra ones to get rid of. I'll see how they are when I get themhttp://www.molex.com/molex/products/datasheet.jsp?part=active/0250010906_CABLE.xml&channel=Products&Lang=en-US Quote Link to comment Share on other sites More sharing options...
Filch Posted July 2, 2009 Report Share Posted July 2, 2009 I also wanted to mention that you can do your own "piping" of the JB Weld by putting it into a ziplock bag into the corner. You then just cut off the corner and you can squeeze out the JB Weld with little mess.I just got my panel from FPE. I'm just waiting on the standoffs from Mouser and I'll finally bring my MB-6582 build to a close. :) Quote Link to comment Share on other sites More sharing options...
fussylizard Posted July 4, 2009 Author Report Share Posted July 4, 2009 Be sure to use tons of JB-Weld to avoid having problems like I did with spacers coming loose on the back of my FPE panel. I'd probably just use a little initially, then reinforce it after the initial coat dries. If your blobs of JB-Weld are too big in the corners you can cut off the corners of the top case like I did (see pics earlier in the thread).Good luck! Quote Link to comment Share on other sites More sharing options...
mmalluck Posted July 9, 2009 Report Share Posted July 9, 2009 **EDIT**I just found this. .100 , 6 inches long, 9 wire. This is near perfect. I have to buy a minimum of 60 of these though. So I will have a ton of extra ones to get rid of. I'll see how they are when I get themhttp://www.molex.com/molex/products/datasheet.jsp?part=active/0250010906_CABLE.xml&channel=Products&Lang=en-USThe 250010902 cable has eight wires and may work better for that reason. If you don't want to buy 60 of these you might want to see if they'll send you some free samples. I'm trying to see if they'll send me a few for my MB. Quote Link to comment Share on other sites More sharing options...
Filch Posted July 11, 2009 Report Share Posted July 11, 2009 The 250010902 cable has eight wires and may work better for that reason. If you don't want to buy 60 of these you might want to see if they'll send you some free samples. I'm trying to see if they'll send me a few for my MB.I already ordered them and I'm already in possession of them :) Quote Link to comment Share on other sites More sharing options...
m00dawg Posted July 14, 2009 Report Share Posted July 14, 2009 I already ordered them and I'm already in possession of them :)In the future, SmashTV offers IDC cables cut to length. Probably not the cheapest if you know you need a whole lot of it, but it's easy to find and works well. Allied Electronics also offers cables cut to length though it's really hard to find on their catalog (I just e-mail them for the part number).How are those heatsinks working out? I'm not ready for them yet but it will be soon. I finally soldered all the LEDs to the control surface. Now I'm stuck on a power issue but I hope to have that finished up soon. Quote Link to comment Share on other sites More sharing options...
fussylizard Posted July 14, 2009 Author Report Share Posted July 14, 2009 How are those heatsinks working out?They worked out pretty well. I had to bend the fins up a bit since the SIDs are all so close together, but other than that they fit perfectly. I've been busy w/ other stuff so I've not yet posted pics about it. Maybe I'll have time tonight before my wife and I go to the midnight show for the new Harry Potter movie. :-)BTW I ordered a +/-12V power supply kit from Paia (turns out they are in Austin, I wonder if they have a storefront or something) for the AOUT_NG module to be controlled by my MB-6582. Should be here today. I figured the $40 or so was worth it to avoid crawling through the Mouser site hunting down all the parts to do it myself.How's your MB-6582 coming along? Quote Link to comment Share on other sites More sharing options...
m00dawg Posted July 16, 2009 Report Share Posted July 16, 2009 How's your MB-6582 coming along?It's getting close! I finished soldering the parts to the CS and now have a working LCD. I also fixed up my power cable so it sucks less and, actually, it works pretty well. Since I'm tapping into the GND, +5, +9 headers directly, I had to get a power connector that would fit on the back panel without causing issues. I ended up getting a 4-pin DIN style connector that screws into the panel perfectly. I also upgraded to larger cabling (harvesting the cables from a bad PSU).I'm still getting a small voltage drop on the +5V, but it seems to be a lot less. Before it was so bad that the backlight was causing +5 to sag way too much. I only have a PIC, the BankSticks, and the LCD connected so far though. I'm going to leave it that way until I finish wiring up the CS, which I may start on as early as today. I haven't quite decided if it's worth using pin-headers or not and I still need to solder the resistors for the LEDs (I think I'm going with 1k).After that, I just need knobs, heatsinks, and to have my power-board fabbed. Oh plus some screws for mounting the mainboard and the LCD. I ran into the same problem you did with lack of tiny screws for the LCD. For now, I just used ones I had lying around from my previous MB SID project and basically threaded the holds on the LCD and CS with them :) That won't last forever, but at least I have something put together that will work until I can get more screws. Quote Link to comment Share on other sites More sharing options...
Wilba Posted July 16, 2009 Report Share Posted July 16, 2009 In case you are interested, you can supply the LCD backlight with a different supply to the +5V... i.e. if you have spare current on your +9V supply, you can use that instead of using the +5V supply. Most LCD backlights draw about 280mA current so it can help a lot if your +5V supply is sagging. Note that each SID draws 100mA on the +5V supply, so there's 800mA just powering 8 SIDs!If you're interested, all you need to do is cut the tracks around the B+ pin so that it is disconnected from +5V, then connect that pin to the new supply, be that +9V or +12V or even pre-regulated supply, it doesn't matter what the exact voltage is as long as it's sharing the same ground. On the MB-6582 PCB, the +5V supply passes through this pin to the components on the bottom of the board, so you also need to reconnect +5V between the P2_CORE1 pot and P1 pot.The backlight circuit basically is a current limited sinking transistor that sinks a constant current through the B- pin, constant for a given voltage that is. The transistor is amplifying the current at it's base, so you need to keep the +5V supply through P1 and through R4 so it's the same current going into the transistor base, and thus the same amount of current being sinked by the transistor's collector.In my tests with low-power LCD backlights which only need 25mA, switching from +5V to +12V on the B+ pin changed the current from 25mA to 30mA (I have increased R4 to achieve this lower maximum of 25mA)... I haven't tested this with high-power LCD backlights yet... it might be relative to current draw so perhaps it jumps from say 250mA to 300mA. UPDATE: with regulated 12V connected to B+, and a 50K (not 10K) brightness pot set to max, current was up around 600mA! and drops to 240mA at around 1/3 the pot range... so if you try this, be sure to test actual current draw and use a 50K trimpot at P1.Also, replacing P1 with a 50K pot can give you more range in brightness, same maximum but a dimmer minimum.If you're interested in tinkering with this idea, I suggest you also add a way of testing actual current draw of the LCD backlight, by breaking the connection where the LCD cable connects to B+ on the LCD, so you can optionally connect your multimeter between the cable wire and the LCD pad and test current. Note that some multimeters have a 200mA mode and a 10A mode, so make sure you don't blow a fuse by testing with a mode that can't handle that limit (assume the backlight circuit might be drawing 500mA to be sure).If you prefer to wait, I'll post some results of my tests with high-power backlights, so I could tell you what works, what's safe, and maybe how to change R4 to set an exact upper-limit on the current draw.Note to other MB-6582 builders - you typically don't need to be doing this if you have a C64 PSU that can happily deliver 1.5A of current on the regulated +5V supply... the "brick" has a massive heatsink and switching the backlight supply to one regulated within the case is only going to increase load on the regulator within the case, leading to (maybe) another 1W of heat that needs to be dissipated somehow, so no advantage really. Quote Link to comment Share on other sites More sharing options...
m00dawg Posted July 16, 2009 Report Share Posted July 16, 2009 Oooh that does sound intriguing although some of that went above my head I'll admit :) I'm not a huge fan of cutting tracks though - although I could do something similar if I just tapped off my +9V input and ran that through a transistor off-board? That or I could just use a spare 7805 if I needed to I take it?The PSU I built is limited to 1A as it just uses a 7805. I've got a big heatsink I harvested from the northbridge of a broken motherboard that, so far, seems to work well. As long as the sagging isn't too bad, I think I'll be ok. I do like the idea of lowering the backlight down further, though. That will work today, but I'll likely switch out the LCD with an orange-backlit one and will want that to be brighter. Quote Link to comment Share on other sites More sharing options...
Wilba Posted July 16, 2009 Report Share Posted July 16, 2009 Cutting tracks is easy and in this case pretty safe... as they are pretty fat tracks and there's no other tracks nearby you could accidentally cut. I typically use a craft knife to make a deep scratch, then use a small flat screwdriver to scratch deeper until it cuts through the copper. You can test with a multimeter to make sure it's disconnected and also make sure it's not shorting with nearby copper (in this case the ground plane).Duplicating the backlight circuit elsewhere could be done... you'd have to disconnect the B+/B- pins on the LCD (typically labelled A/K at pins 15/16) and use separate wires from the LCD so it's not connected at J15_CORE1.I just realised though, you don't need to break the connection at the LCD to test it's current draw, if you're doing the fix on the PCB, you can test current through the new wire where it's connected to the different supply. Quote Link to comment Share on other sites More sharing options...
m00dawg Posted July 16, 2009 Report Share Posted July 16, 2009 Ahh good point. It's something to think about. I think I'll play around with it once I see how much space I have left-over. The top right corner of the mainboard is empty since I'm regulating outside the case so I could use that space to try and put in a small circuit if I didn't want to cut tracks.I'm not sure I'll be able to test this all that soon though but if I do I'll let you know (assuming you haven't done the same test yourself by that time).Thanks, as always, for the excellent advice Wilba! Quote Link to comment Share on other sites More sharing options...
fussylizard Posted July 17, 2009 Author Report Share Posted July 17, 2009 Speaking of power supplies, last night I built the +/- 12V power supply kit from Paia. After all the MB-6582 soldering (with all the parts so close together and small pads) it was a breeze, with miles between parts and pads. I'll post a pic later (POIDH). I've not tested the supply or tried to power the AOUG_NG yet but I'll report on it later.OT sidenote: I've been having some good fun with an Arduino board and some serial tri-color LED modules this week. Is it just me or does Arduino and the related items feel like building Legos? You just connect all the boards together with jumper wires, paste the supplied sample code into the Arduino IDE, and <viola!> you have a working microcontroller app. Fun stuff. (I'm about to interface it to an accelerometer that is not "plug and play" so it's time to turn my brain back on. :-) Quote Link to comment Share on other sites More sharing options...
m00dawg Posted July 17, 2009 Report Share Posted July 17, 2009 The Arduino stuff is pretty cool. Some of the guys at my local hardware meetup use it for various things. Not as hard core as directly programming an AVR (or PIC for that matter) but still pretty awesome depending on what you want the thing to do.I've wanted to start playing around with these guys eventually, but the MidiBox projects will have me plenty for quite some time. Quote Link to comment Share on other sites More sharing options...
fussylizard Posted July 18, 2009 Author Report Share Posted July 18, 2009 As promised, here's some pics of the Paia kit.First pic is what comes in the kit. I was a bit surprised that the kit used a 12VAC wallwart transformer. I was expecting a 15VAC wallwart to make up for the voltage drop over the 7812/7912 regulators, but I emailed Paia support and they told me the circuit used a voltage doubler to prevent the voltage drop (so that's why it has so many large caps!).Second pic is the assembled power supply kit connected to an AOUT_NG. I had initially tried testing the AOUT_NG with a PC power supply but I was going crazy with all the wires running everywhere. It sure was nice just to hook up a small ribbon cable and be up and running. Calibration was straightforward once I realized my multimeter probes had GND and CV swapped (duh!).Third pic shows my MB-6582 connected to a Moogerfooger lowpass filter. The MB-6582 has an LFO modulating the filter cutoff via the AOUT_NG. I haven't done anything worth recording yet, but when I have something interesting I'll post it.I'm not sure how clean the output of the power supply is. It is designed to power a Paia modular synth, but it works fine. So far I can recommend it as a simple option for powering an AOUT_NG. It's $42 + shipping. You might find cheaper, but it seems to work well and no parts scrounging on Mouser or Digikey required.Now to sort out a case to hold these boards...I'm also thinking about trying to combine this with a MIDIBox CV. The basic idea would be if the MB-6582 is powered up and plugged in, the AOUT_NG would ignore the MIDIBox CV core. I probably just need to multiplex the signals going to J1 on the AOUT_NG and select between the MB-6582 and a MIDIBox CV core. I can detect the +5V coming from the MB-6582 to select the appropriate source for J1. Should be straightforward, right? I guess the first step is finding some sort of multiplexer that can pass analog signals. If anyone has any recommendations that would be great (maybe the Maxim 4702 4xSPDT analog switch assuming it is available in a hand-solderable package?).IMG_4347-paia 9700R12 power supply kit parts.JPGIMG_4350-AOUT_NG with power supply complete.JPGIMG_4351-testing AOUT_NG with MF-101.JPGIMG_4347-paia 9700R12 power supply kit parts.JPGIMG_4350-AOUT_NG with power supply complete.JPGIMG_4351-testing AOUT_NG with MF-101.JPG Quote Link to comment Share on other sites More sharing options...
m00dawg Posted July 18, 2009 Report Share Posted July 18, 2009 Looks pretty cool! Love to hear a few demo/samples :) Quote Link to comment Share on other sites More sharing options...
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