fussylizard

Hi, I'm hoping for a sanity check here. I just finished testing my MB-6582 baseboard (using SmashTV's kit) with the SID testtone app (bridging pins 8 and 27 on the SID sockets) and discovered that I get a 1Khz tone out of all SID sockets EXCEPT U1_SID1 (second from right). Here's how I tried to narrow it down to the CORE1 PIC: - LCD on CORE1 has normal messages (SID Testtone Generator) + I get the upload request for CORE1 on MIDI In monitor in MIOS studio when CORE1 is selected for output on J11 ==> CORE1 PIC is powered up and partially working - Verified output buffer circuit for non-working output by bridging pin 8 on a working SID socket to pin 27 of non-working SID socket ==> Worked, therefore the output buffer is OK - Tested continuity from pin 8 of non-working SID socket to pin 24 (fourth from bottom right) of CORE1 ==> Worked, so no problems between CORE and SID socket. - Swapped CORE1 and CORE2 PICs. Audio output now fine from both SIDs on new CORE1. Output from original CORE1 not working. (I can't remember if I tested both SID outputs on the original CORE1.) ==> CORE1 section of PCB is fine - Swapped PICs back. Now neither SID output connected to CORE1 works. All 6 other SID outputs work fine. ==> ??? - Re-tested output buffers of first two SID sockets from other good SID sockets ==> Works, so output buffer circuits still OK - Tried bridging output pins (pins 24 and 27) on CORE1 PIC directly to output buffers on SID sockets (pin 27) ==> Failed, so apparently I'm getting no output on those PIC pins I also tried re-uploading the testtone app (selecting CORE1 on J11) and I cannot re-upload the app (first block sent, no response from PIC). I tried to re-upload the testtone app onto the other COREs and it fails to upload on them also, so this is not unique. (IS THIS NORMAL BEHAVIOR? I THOUGHT I COULD UPLOAD APPS AS MUCH AS I WANTED?) Hmm, I should probably try removing CORE1 and re-trying the upload. (NB: I uploaded the testtone app to each CORE in its own socket, so MIDI In/Out was working fine initially.) So unless figuring out why I can't re-upload the testtone app uncovers something, it seems my PIC output pins (27 and 27) are dead. Am I missing something obvious here? Any ideas before I order a new PIC? TIA, Chris

Update: I got the PSU section built out and tested. I inadvertently swapped V2 and V3 (I'm using PSU option B), so I had to fix that. Getting those regulators out was a huge pain since the leads are large and require lots of solder. The solder sucker and solder braid were not working, but I finally used some Chip Quik and that did the trick (I bought some for my MidiBox CV in case I mess up soldering the surface-mount DAC). Fortunately I caught it while doing the recommended voltage checks, so no harm no foul. I also bought heat sinks for the regulators that didn't quite fit. I knew board space was tight so I got heat sinks that only stuck back .25" behind the regulators, but that was still enough that V1 and V3 were touching. I ended up grinding off the left-side "fin" for V1 and now everything fits with a little extra space to prevent shorts. I'll post a pic once I'm further along. Anyway, I'm ready to test out the first core, but I have some other work to do so it will have to wait. :-(

Well I have a bunch of large-ish cheap clamps, so I should be good. Thanks for the info. Question: The Base PCB has lots of holes with nothing in them. I'm assuming these are just vias? I have a few instances in which I accidentally soldered these holes shut. There is no short with anything and no part is labeled to go there. Is this a problem? I got solder out of most of them (solder sucker and/or braid), but I had a couple that I couldn't easily fix, so I left them for now... I'm calling it a night. I've soldered from 2 p.m. to midnight with a few breaks, so maybe 8 hours total. I have the stuff I mentioned earlier done, plus all headers, jacks, base section caps, and the power switch. Next step is to build out the PSU and test it, then move on to the core and SID sections. Buenas noches...

Update: I've been soldering the base board for about 6 hours. Resistors in, diodes in, in-socket caps in, sockets in. I'm about to cut up the headers right after dinner. Everything is going pretty smoothly. I'm checking each joint with a 10x loupe (from curiousinventor.com; they have a great "how to solder" video that improved my technique a lot). I've only had to fix a handful of joints, which is good. More to come...

Makes sense. I can sort of see this. Once I have my front panel and all that JB Weld down it will probably make *much* more sense! :-) Yeah, same here in the US. I have a bunch of clamps already but since they are pretty big I'll probably get some small decent ones (per Nebula's recommendation). My watchword for this project is "fun" (as opposed to say "super cheap"), so a few $ for clamps is worth it to take away frustration! @Morten - I'm going to grab some lunch and then start soldering! I'm glad the recommended order starts with resistors since they are hard to destroy. :-) My soldering skills are a bit rusty, but by the time I get all those resistors down I'm sure I'll be a pro! :-)

Wow, thanks for the tips, all good stuff! I hadn't noticed that cap on its side, so thanks for keeping me from messing that one up! I ordered the ALPS switched recommended by Wilba which are 100 gf, so good there. As for the clamping, can't you just set some heavy books on the whole setup and avoid clamps altogether? I'm really excited about the synth. It will also be great for taking with me on work trips since it is small and self-contained. Thanks again for the tips. If you think of anything else please pass them along! Regards, C

Quick update: I got my SmashTV order (impeccable as always) on Wednesday so I can get started. I'm still awaiting my front panels (FPE), SIDs, and knobs, but I have everything else and will start on my baseboard this weekend. I'm also keeping a list of my questions as I go that may be useful for others later. One thing I'm amazed about is all the information that is there. I've been reading over the info, and pretty much every question I've had was answered somewhere. So advice for those starting out: read everything, and read it several times. It's a lot to take in at once so the first time or two I read things I skimmed over some details, but later when I re-read things my questions were answered. :-) Morten & Flemming, good luck!

Good suggestions, thanks. My Mouser and CrystalFontz orders have arrived, so once I have my boards from SmashTV I can get started. Also I'll be out of town for work next week so it will be a bit before I get started. If you think of anything else please let me know and I'll see what I can do. Thx, C

Hi all, I'm starting to build a MB-6582. First I would like to thank TK, Wilba, SmashTV and the rest of the MIDIBox community for putting together such a fantastic project. I'm super excited and can't wait to get going. I've spent ages reading up on everything and think I have a decent handle on everything. I've ordered everything except the front panels so far, and am just waiting on the various orders to arrive (SmashTV, CrystalFontz, Mouser, McMaster-Carr, knobs from Goblinz's bulk order, SIDs from Wilba's mega-sale #9). The documentation is pretty good overall (thanks again!), though some digging and thought is still required to get everything pulled together. Pretty much every question/issue I thought of was addressed somewhere. I've seen a number of MB-6582 build threads already, so I figured I'd ask if there was anything in particular that could use some additional documentation as I go along. Once I have verified I ordered the correct part #s I can supply Mouser part #s that can be added to Wilba's excellent lists so far, and of course I can take some photos of things as I go along to enhance the build instructions. If there are any special requests for documentation of my build, let me know and I'll see what I can do! Thanks, Chris

13 to go.

It's not just you. I've ordered stuff from Smash's site before (what a godsend- thanks SmashTV!) and was looking all over for the MB-6582 boards and missed them also. I thought the Wiki posts were old or something. Then I saw this recent thread and checked again and duh, there they were. I guess I just needed a good night's sleep... :-)