NorthernLightX

Post a (closeup, high detail) picture of your board please, it's easier to see obvious mistakes that way. To me it sounds like a broken regulator. Your adapter could deliver more than the rated 9v if your mains power is also higher (could be 10%, so 12v instead of 9 is very high! cheapo powersupply perhaps?)

No problem, but take into acount that the rectifier will eat 0,7V of you input voltage. I don't think it's a good plan, look at the optimized SID psu: it uses Core:J2 to get the power in, and thus omits the rectifier too. If you're really paranoid about swapping the polarity by accident, use plugs and sockets that can only be connected one way. A 3 pin SIL header could also do the trick: mount it in the place of the regulator. Then use a female SIL (also 3 pins) and solder the GND to the middle pin, and +5V to one of the outer pins. Leave the other pin blank. Now, if you reverse the plug by accident, you will apply +5v to the wrong track, but that's no problem because there's nothing mounted there. Get the picture? Cheers, Alex.

Hi, sure, you can remove all the following parts if you supply the Core with regulated 5v: rectifier, 2200uF elco, 330nF kerko, regulator (has to be removed), and if you like the 10uF and 100nF caps can be left out too. If you want to keep it simple: leave out everything before J2 and remove the regulator. Cheers, Alex.

Excuse me Thorsten, that was not wat I implied at all! I really hope your holidays were nice and all, I didn't even know were away. I assumed that the PM system was malfunctioning or perhaps my connection with internet did strange stuff, and the message never arrived. I didn't want to send it again and sound like I was demanding a quick answer. Nor was that the reason of this post: impatient as I am, I was wondering what other people tought about the design changes. Lastly: Even if you did find my msg ininteresting and choose not to reply I'd respect that and all, after all you've given birth tot midibox, whereas I just rerouted some silly tracks. (Besides I'm not used to such behaviour from you at all so pleae believe me that I never assumed that.) So, can we still be friends and all? ;D ;) Alex.

Hi, I've been playing a lot with Eagle lately, and when I was looking at the board layouts of the AOUT and burner modules I noticed that some of the jumps are not necessary. After some trying, I managed to remove all the jumps from the boards. I PM'ed TK about this but he must have never received it, missed it, or think this is totally not interesting. Anyway, Im posting them on the forum now, so anybody could have a look: http://home.quicknet.nl/qn/prive/alex.span/midibox/mbhp_aout_v1_bridgeless.brd http://home.quicknet.nl/qn/prive/alex.span/midibox/mbhp_burner_v1_bridgeless.brd Cheers, Alex.

Lovely stuff drin! That issue with the buttons on the 4th channel sounds all to familiar, reminds me of when I was drilling a hole in the back of my case for a MIDI plug, and suddenly realized the friggin transformer was sitting in that very spot on the inside... ;D Your case looks quite nice, although I would have liked a "sloping" tabletop case even better. Is there a special reason why you kept it flat? The only big question remains.......where's that heatsink on the 7805? ??? ;D Cheers, Alex.

Hey, do something right or don't do it at all is the motto! 8) I am very new to this, but much reading and discussing stuff with people who do have the knowledge helps a lot. ;) Besides, this might becoma FAQ stuff, and if the proper documentation can already be found in this thread that leaves a job of only cutting and pasting when the testing phase is completed. Now, if only those biatches at Reichelt would be a little quicker at answering my email.....

That depends on what you're planning to run on it. If your total load on the positive branch does not exceed 1,25A it is sufficient: With 50VA, you have 25VA per branch (in my design, this will be the positive and negative branches). 25VA at 12V means a max load of 2,0833 Ampere behind 7812, 7809, and 7805 combined. The 7912 on the other hand has the total of 2,0833 A for itself. With 30VA, you have 15VA per branch. 15VA at 12V means a max load per branch of 1,25A. Note that each 78xx can handle a max current of 1A, it is not possible to exceed that. So for example, if your setup draws close to 1A on the 5V branch, with a 50VA trafo you still have more than 1A left for the combined 9V and 12V branches. With a 30VA trafo your headroom in this situation is only about 0,25A. I hope this answers your question ;) Cheers, Alex.

The toroid trafo will weigh a few grams too, keep that in mind...

Dan heb je na je examens mooi tijd om mij in te halen, ik heb mot met Reichelt over de bestelling en zonder die onderdelen kan ik niet verder...

That would be very strange, the cap wasn't that hot at all, and the air wans't damp either. It's actually pretty arid in my house...

You <might> want to consider ordering your new boards from SmashTV's shop when it gets online again (might be a week or 2). To be blunt: his new boards are far better than Mike's. No more bridges, no more oxidation of copper tracks, better planning of component placing, and last but perhaps the best feature: preparation for easy cabling of your other modules/veroboards with DIL sockets. Cheers, Alex.

Hi Adam, I'm not angry at all, your post just had an odd sound to it (as far as reading does produce sound ;) ), so I felt like pointing that out while pointing you in the direction of the broccoli at the same time. The thread is indeed an old one, but with a very recent reply announcing success, and it's cheap, so I thought you might be interested. Don't have any experience with it myself though, but you can take Martin's word for it's simplicity and cheapness. If you lack the money for buying PICs you could always request a sample from Microchip. Please do post your recipe for fried PIC, I think we should have a dedicated section on the forum called "The Cookbook" or something, with nice recipies like that. I know of a few members who could contribute a few of their own experiences to the cookbook ;D Cheers, Alex.

Gee, the way it sound to me is like "Hi! I, m really impatient and don't feel like doing this stuff myself, isn't any of you guys around here crazy enough to do my work for me!?" So, assuming I totally misunderstood your post: why don't you read the topic on the broccoli burner. It's like ONE (1) topic below this one in the list. Good luck ;)

I finally found out how the polygon option works :) Pics have changed slightly, and by replacing one of the 4700uF elco's with a 2200uF, another 54 cents can be saved :P I've placed an order at Reichelt for the parts, and Mendelt, Wisefire, and myself are going to betatest the design. PCB's will be ready in 3 weeks (not for resale, sorry, but when the design is tested and found ok I will release the schematic and the .BRD to the community so no worries ;) ) Chees, Alex.

[update] Alle images were moved to the WIKI: http://www.midibox.org/dokuwiki/northernlightx [/update] As the board had to be slightly bigger to accomodate the 9W resistor, I reserved a little (and i mean a little but it could have been less ;) ) space around the SIL headers for easier access, as per stryd_one's request. Preliminary orderlist @ Reichelt: +----------------------------------------------+-------+--------------------+-------+--------+ | Description | Qty | Part # | Price | Total | +----------------------------------------------+-------+--------------------+-------+--------+ | Voltage Regulator 7805 | 1 | uA 7805 | 0.17 | 0.17 | | Voltage Regulator 7809 | 1 | uA 7809 | 0.17 | 0.17 | | Voltage Regulator 7812 | 1 | uA 7812 | 0.17 | 0.17 | | Voltage Regulator 7912 | 1 | uA 7912 | 0.17 | 0.17 | | Resistor 220 Ohm | 1 | 1/4W 220 | 0.10 | 0.10 | | Resistor 4 Ohm 5W | 1 | 5W AXIAL 3,9 | 0.29 | 0.29 | | Resistor 8 Ohm 9W | 1 | 9W AXIAL 8,2 | 0.36 | 0.36 | | Polarised Capacitor 4700 uF | 1 | rad 4700/35 | 1.00 | 1.00 | | Polarised Capacitor 2200 uF | 1 | rad 2200/35 | 0.46 | 0.46 | | Polarised Capacitor 22 uF | 4 | rad 22/35 | 0.06 | 0.24 | | Ceramic Cap 220 nF | 2 | Z5U-2,5 220n | 0.13 | 0.26 | | Ceramic Cap 100 nF | 4 | Z5U-2,5 100n | 0.06 | 0.24 | | Diode 1N4008 | 4 | 1N 4008 | 0.02 | 0.08 | | 1-row SIL Headers (about 14 pins) | 1 | STIFTL. 40G | 0.18 | 0.18 | | Ringkern/Toroid Trafo 2x12V 50VA | 1 | RKT 5012 | 12.30 | 12.30 | +----------------------------------------------+-------+--------------------+-------+--------+ | Total 16.10 | +--------------------------------------------------------------------------------------------+ Note 1: Heatsinking of the 78xx regulators is a must. It's possible to create a heatsink from a piece of aluminium that you cold attach to all 3 regulators. Note 2: The 7912 regulator has a different pinout than the 7812, the metal slab is 12V in, so take the necessary precautions if you want to heatsink it! Optional parts (not necessary but very handy!) +----------------------------------------------+-------+--------------------+-------+--------+ | Description | Qty | Part # | Price | Total | +----------------------------------------------+-------+--------------------+-------+--------+ | Female Power plug | 1 | KES 2 | 0.69 | 0.69 | | Fuse holder | 1 | HALTER 10,3X38 | 2.10 | 2.10 | | OR Combined Power plug + Fuse | 1 | KES 1SI | 1.35 | 1.35 | | Power switch | 1 | DS 059 RT | 1.55 | 1.55 | | 1-row FEMALE SIL Headers | 1 | BL 1X20G8 2,54 | 0.34 | 0.34 | +----------------------------------------------+-------+--------------------+-------+--------+ As usual: any comments are welcome. I really hope this was the last design change ;) Cheers, Alex. [edit] Last minute change: the elco on the -12v rail has been replaced with a 2200uF specimen. Saves you another 54 cents ;) (and NO changes to the layout for a change! :D ) Also I added another image, of the copper tracks without the components. [/edit]

Indeed, the only component you need to change is the transformer, exchange it for a specimen that converts 115Vac into 2x12Vac. After that, all components are the same. Please do note that another change to the design is being made: if an 8 Ohm resistor is going to be used, it also has to be at least 8 Watt. So, you only have to swap it then, right? Wrong, this baby is even bigger, and I have to create a new board (again) because the stuff doesn't fit anymore >:( Almost finished, will post it tonight.

Weetjewat? Ik heb zelf hier ook nog een aantal modules liggen die ik niet gebruik, ik ga dat eens aan elkaar solderen (in afwachting van de heropening van de Shop van SmashTV) en dat moet dan een SIDbox worden met 2 extra encoders voor Cutoff en Resonance. ;) (samen aan iets klooien is altijd leuker dan allen toch?) Ik wil dan wel gelijk LEDrings om de rotary encoders natuurlijk. Heb gisteravond een mooie LCD kabel gemaakt, mijn Core en LTC getest (op de LTC moeten alleen nog wel bypass caps, en ik ga ws de elcotjes voor de monoflops vervangen voor 1uF-jes, dan knipperen de LEDjes van de MIDI in en out wat sneller). DIN en DOUT en SID heb ik klaar liggen voor verdere modificatie maar ik ben door mijn female SIL headers heen, moet dus wachten op de Reichelt bestelling... (zullen we hier anders een nieuw topic voor openen?) Gr, Alex.

Hi, if the PSU you're using already has regulators on board for 5V and 12V I wouldn't stuff te regulators on the boards (unless you're using 8580 SIDs, then you should stuff 7509 or 75L09 on the SID boards). The 5,58V is fine for the Core, 12,08 is also fine for the 6581 SID, or to feed into the 7809/78L09. The following text is a statement of which I do not know if it is 100% correct, read my topic on the Midibox PSU for details and/or a reply from someone who can confirm the statement. Remember that if your PSU is not regulated, the voltages you measure now could be up to 20% higher if you plug in the PSU at an other location! In that case, it might be wise to DO stuff the regultaors on the Core and the SID, even if you use the 6581. Cheers, Alex.

I've had a few old ceramic caps (brownish colour) lying around, and used them for bypass caps on a DIN module. When heated for the first time all of the disks became a litte wet all by themselves, and on the newspaper I had lying underneath the boards actually was a little wet spot. I don't believe it's broken, I think more of a protective coat or something that got heated away... Cheers, Alex.

One last thing, about the rating of the big resistors. For the not so techical readers (like me!): The theory behind them is as follows: They will dissipate an amount of Volts equal to the amount of Ohm they're rated for, at a current of 1 Ampere. If the current is less than 1A they will dissipate less, but the regulators will be stressed less too, so this is exactly what is wanted. I'm not 100% sure if the rating of the resistors is good in the current design. I did some quick calculating after learing about the above rule yesterday: The power out of the mains can be plus or minus 10% of the specification (115V or 230V). Let's assume its -10%, as it is in my house. So, instead of the 12V the trafo delivers at 230V, it in fact delivers 10,8V (12V - 10%). When rectified and filtered, the voltage becomes 10,8V * 1,41 = about 15,23V. this is perfect for the 7812 and 7912, so far so good. If we assume (for simplicity's sake) that there's a load of 1A behind the 7805, the resistor R1, which is rated for 5 Ohm, will dissipate 5 Volts. But since the voltage after the rectifier is 15,23V, there will still be 10,23 V left, a tad high for my taste. At the 7809 it's the same story, 15,23V - 2,5V is still 12,73V. The difference here is a little less disturbing, but note that these numbers are the best case scenario! If for example the mains is not -10%, but +10%, the voltage before the 7812 and 7912 is 12V * 1,1 * 1,41 = 18,61V. Not something to worry about if you got a decent heatsink on them. But for the 7809 an 7805 it's a different story, they will be fed with 18,61V - 2,5V = 16,11V and 18,61V - 5V = 13,61V. I find that much too high. I could be paranoid and/or have misunderstood the calculations to take, so if anyone sees flaws in my logic please reply! :) My suggestion would be to replace the 5 Ohm resistor for 8 Ohm, and the 2,5 Ohm resistor for 4 Ohm. That way the calculations would be as follows: voltage @ 7805 @ -10% = 15,23V - 8 = 7,23V voltage @ 7805 @ +10% = 18,61V - 8 = 10,61V voltage @ 7809 @ -10% = 15,23V - 4 = 11,23V voltage @ 7809 @ +10% = 18,61V - 4 = 14,61V These are values anyone should be able to live with :) As usual, comments are welcome! Cheers, Alex.

It's a new underlying BBS, right? Or was YABB abandonned earlier? I like the skin. Suggestion: I used to run a very small scale forum, and have a kick-ass smiley pack. Might be cool for the new forum layout? ;) Cheers, Alex.

OK, I couldn't help but make some minor adjustments :D The top right mounting hole is now easier accessible, since the elco isn't over it anymore. I haven't found the Copper Fill option yet, any hints? Cheers, Alex.

Oh I knew you didn't use my design, that would be quite hard since it's only been up for a day or so :) . I meant that the partlist will include overrated stuff to prevent faults like you had. Anyone who want's to build this PSU should note carefuly, that polarization IS an issue if you also decide to not stuff the rectifier and stuff on your boards. It might be a good idea to color code the connectors in some way ;) I'm not going to change the design if there are no technical reasons. the connectors are easy enough to reach as long as you make use of female SIL plugs for the connectors (only the big elco's are "high" components). Soldering directly to the headers might be a bit of a problem, but I do not recommend that anyway. Cheers, Alex.

[update] Alle images were moved to the WIKI: http://www.midibox.org/dokuwiki/northernlightx [/update] At last, this should be ok. As by Moebius' advise, I placed the 7912 away from the other regulators, to avoid people attaching them all together on a heatsink. The 7912 should stay cool enough without a heatsink anyway. Cheers, Alex.