Molom

Hi Peter, Thanks for the clarification! Yes, Sauraen's project looks amazing, but unfortunately well beyond my current skills. Would it be fine then to use one of the PIC18F4685 chips that I have left over from my MB-SID build? I suppose I could save the STM32F4 module for a different project, or sell it for that matter. No big deal. Regards, Theo

Hi all, After having previously built an MB-6582, I thought I'd have a go at building a midibox FM. Following TK's build guide on ucapps, I've built the OPL3, DIN, DOUT, and CORE modules using PCBs ordered from Modular Addict. For the core, I thought it would be fine to use the newer STM32F4 module because it is mentioned as a more modern alternative to the PIC-based one. However, only after finding out more about it (my mistake), I'm now unsure if that was the right choice. I don't want to try to replicate Sauraen's 2.1 version because it looks far too ambitious for me and I need to rely on something fairly well documented and straightforward. My coding skills are very basic, and I just want to use the control surface of TK's 1.4 version. Is it possible to build the 1.4 version using the STM32F4 without writing or changing a lot of code myself? Or would I be better off using an LPC17 or a PIC-based core instead? I already have some spare PIC18F4685s, but I suppose if I use an LPC17 then I won't have to add a midi IO module later. Is that correct? I appreciate any advice. :-) Cheers, Theo

Hope I'm not flooding the market here, but I also have four pre-programmed PIC 18F4685s for sale. The price would be what I paid for them from mikes-elektronikseite + shipping. I'm in New Zealand, so it could be good for someone in this corner of the world.

Thanks Zam! I will search more persistently next time!

Hi all, I'm in the process of collecting all the components needed to build a Midibox FM, and I have a few questions about the 14.318 MHz crystal oscillator used on the OPL3 module. If I were to get the one listed by TK on Reichelt I think the shipping (to NZ) would be pretty expensive. Does anyone know where I could find an appropriate oscillator from an alternative source like mouser or ebay (or from a midiboxer with spares)? I'm not that confident about knowing what else might work. It's hard for me to tell, but looking at the pcb layout it seems that it accommodates two different package sizes. Is that correct? Cheers, Theo

I managed to fix the problem by... not doing anything special. I just carefully reattached the CS to the front panel, testing the switch as I went. Incidentally, I really hate opening up the unit. Almost every time I do so, I break at least one of the wires on the JD pads.

Thanks for the suggestion Goyousalukis. I think I know the firmware you mean. I found this useful though: http://wiki.midibox.org/doku.php?id=control_surface_troubleshooting I've discovered that the problem stops if I completely detach the control surface from the aluminium front panel, which would indicate it's causing a short somewhere. I think I can isolate it and fix it, but It's 3 am now so that'll be a job for tomorrow.

Hi all, My beloved MB-6582 has developed a problem with the rightmost menu button, i.e., the one used to select the SAV page. It used to work, but now when I press it, it selects either the ENV or MOD page instead, irrespective of what page is actually shown above it. This means I’m no longer able to save any patches. Does anyone know what the cause might be? Hardware or software? I’m not sure how to begin diagnosing it. Thanks in advance for any help.

Hi Peter, Good point, thank you. I will look into the adhesive thermal paste.

What if I were to use a nonadhesive thermal paste? Would the paste still keep the heatsinks sufficiently in place or would they be liable to slide off if I move the unit around?

That is a good option and I have a dremel. If I hadn't placed an order with Retroleum last night I would have gone with that. Thanks for the suggestion.

I'm looking to buy 8 to 10 low profile heatsinks, such as the Fischer Electronik ICK 28 B, which would be suitable for the SID chips within an MB-6582. The only places I've been able to find them are Retroleum (which sells 24 pin versions) and German sites (Bürklin / Reichelt) where the quoted shipping cost of ~€42 to send to New Zealand seems a bit excessive. Does anyone have a few spares they could sell with reasonable shipping prices to NZ? Cheers, - Theo

Ah! *headslap* I've seen that photo before, but I failed to notice the wiring at the pot. Thanks so much!

Now I'm really confused. In all the pics I've seen it looks like the three pins of the pots are wired directly to the three header pins. Is something further necessary? Apologies for the noob questions, I'm just trying to understand how it works.

Thanks Jaytee. Like you, I also had the problem that my LCD backlight wasn't dimming, but thanks to your thread earlier this year I learnt about the workaround with jumping B+ and B- with an LED. I'm already thinking about upgrading to an OLED. In addition to my question about the jumping filter cutoff values, I'm also wondering what exactly are the feedback pots supposed to do? I've used dual-gang 100K pots, but as far as I can tell all they do is mute the channel when turned hard one way. Am I missing something obvious here?

After nine months of patiently sourcing components from around the world and several nights of soldering (and desoldering), I'm happy to say my MB-6582 is more or less finished. It's my first (working) diy synth, and I'm very satisfied with the results. Big thanks to TK, Wilba, and Smash TV for making this possible. It's populated with six 8580 R5s and two more are on their way. Things still left to do are: install the feedback pots and expansion port connector drill holes for the bottom vents and the 6.5mm audio jack eventually upgrade the cheap plasticky knobs install a display window install low profile heatsinks (can anyone point me to a source for these?) I also have one small issue - the filter cutoff value seems to jump around a bit when I change it, especially if I make slow adjustments. I've kept the detention on all my encoders. Is this behaviour normal?

Ok, I figured it out. The LED issue was due to me not soldering the 'optional' bc547s. And I fixed the non-responsive buttons/encoder problem by replacing all the 74HC165s. Whew! Thanks for taking the time to respond borfo and jaytee :-)

Hi everyone, I've just finished soldering a MB-6582 CS and connecting it to the base PCB. The trouble is, while the base PCB & display seem to work fine (through mios studio), almost nothing works on the control surface. No LEDs light up, and no buttons or encoders work except for the menu encoder (kind of), which can scroll randomly through the patch menu briefly before stopping. After that, subsequent turns only make one character flash. I'm fairly confident my soldering work isn't the problem. The only other things I can think might be the cause are that: I initially had one of the 74HC595s round the wrong way with power on. That IC got extremely hot so I cannibalised my broken Shruthi for a replacement. Before soldering the CS, I tried to temporarily connect it to the base PCB with loose connecting wires and I may have shorted one or more of them. Is it likely to be a fried 74 chip? What would be the logical steps for troubleshooting this? I'm aware of this post: No LEDs lighting on MB6582, but I haven't tried testing the LEDs yet. It's frustrating to have this problem while being so close to finishing. Any help will be much appreciated!

Thank you Gerald. I'll give that a go.

You won't find any clones. Your best chance is to contact Tim at Midibox Shop and be patient.

Hi guys, I've finished building the base of a mb6582 (including display) and so far everything seems to work as it should (Woohoo!). However, after reading Hawkeye's CS tutorial, I've delayed soldering components onto the control surface PCB until the front panel that I've ordered arrives. Until then, I'd like to rig up a minimum CS using a breadboard and switches/encoders for basic parameter changes (menu scrolling, etc). Is this possible, and if so how? Even with TK's instructions I'm not quite sure how to go about it.

As the title says, If anyone has a spare set of front and rear panels they want to sell then I'd be interested in buying them. I'm not too concerned about colour or condition, only that the price including shipping to New Zealand beats what I'd need to pay to fabricate a new set.

Hi Jaytee, This is possibly a long shot but do you have any of those panel sets left for sale?

Yes, Tim got in touch with me but unfortunately there's an insurance issue with shipping to South Korea. I'm waiting to hear back about shipping to an alternative address.

I really hope not. Tim told me he'd put aside a set of PCBs for me, but since providing me with a quote I haven't heard back from him for over two weeks, which is slightly concerning. Has anyone else been in contact with him?