space6oy Posted May 13, 2010 Report Share Posted May 13, 2010 aside from having assembled a x0xb0x and switched out some lights & chips in other synths i'm still an amateur with electronics - can someone please tell me what the scenario is with the voltage checking before installing either the 22nf or 470pf capacitors in C1L, C1R, C2L & C2R? seems like that's mentioned in the parts list but skipped in the walkthrough. Quote Link to comment Share on other sites More sharing options...
Wilba Posted May 13, 2010 Report Share Posted May 13, 2010 It's clearly explained in the section 8. Installing SIDs of the build guide. Quote Link to comment Share on other sites More sharing options...
space6oy Posted May 13, 2010 Author Report Share Posted May 13, 2010 thanks - it's very odd how the guide is arranged differently from the order suggested by the parts list. hadn't gotten to that section yet. Quote Link to comment Share on other sites More sharing options...
space6oy Posted May 13, 2010 Author Report Share Posted May 13, 2010 (edited) just a heads up, also there's not really a conclusion to this sentence in the backlight voltage/current jumpers section: "Thus, leaving this header open will enable R4A and reduced current, a shunt in this header will disable R4A and the." Edited May 13, 2010 by space6oy Quote Link to comment Share on other sites More sharing options...
Wilba Posted May 13, 2010 Report Share Posted May 13, 2010 Thanks for the bug report. Changed to "Thus, leaving this header open will enable R4A and reduce the current, a shunt in this header will disable R4A and the current will be higher." Quote Link to comment Share on other sites More sharing options...
space6oy Posted May 14, 2010 Author Report Share Posted May 14, 2010 no problem, thanks for the help! have another question for you, i'm short one 6 pin 10k ohm resistor & am having a rough time finding one w/o ordering a batch from jameco. guy in an electronics shop is trying to find one for me, but didn't today & isn't open for the weekend, but he told me if he doesn't find one he thinks he can show me how to make an alternative... i have a stockpile of extra resistors, but no multi pins... any suggestions? or must i wait it out? 3 steps away from having this finished up, will drive me nuts! Quote Link to comment Share on other sites More sharing options...
Wilba Posted May 15, 2010 Report Share Posted May 15, 2010 I apologize for the missing resistor network, I don't know how that could happen, as I definitely count four per kit, and I'm pretty good at counting to four, been doing it for three decades now. :tongue: I will send you a replacement today, but if you can't wait (or want a temporary fix), you can use five 10K resistors... solder them vertically in the pads that DON'T have the white dot next to it. Then solder a wire vertically in the pad that has the dot next to it. Bend that wire and solder it to the other ends of the resistors, so all the resistors are connected to the "common" pad (with the white dot). I've done this before with home-made DIN modules, it's a bit ugly but works. If you don't have 10K resistors, then anything between 1K and 50K will work just as well, they don't have to be all the same value either. If this is a temporary fix (i.e. you do want to replace it with the right part, right?) maybe leave some room so you can cut the resistors off near the PCB and remove the leads individually. Quote Link to comment Share on other sites More sharing options...
space6oy Posted May 15, 2010 Author Report Share Posted May 15, 2010 no apology necessary, it's totally my fault. mistook them for machine pin strips on C1 & 2. removed one safely but couldn't get the other out w/o losing a couple pins. tried to attach replacements but it's too awkward for me. :( thanks a ton for offering to send a replacement, and for the alternative route - almost sure i have plenty of 10k resistors, will give that a shot & leave room to switch them out again! Quote Link to comment Share on other sites More sharing options...
space6oy Posted May 15, 2010 Author Report Share Posted May 15, 2010 that was ridiculously lucky - strip of exactly 5 10k resistors, first thing on top of the pile in my parts box! Quote Link to comment Share on other sites More sharing options...
space6oy Posted May 15, 2010 Author Report Share Posted May 15, 2010 Quote Link to comment Share on other sites More sharing options...
Wilba Posted May 15, 2010 Report Share Posted May 15, 2010 Cool! That will get you going until your replacement gets there, maybe before next weekend if you're lucky. Quote Link to comment Share on other sites More sharing options...
space6oy Posted May 16, 2010 Author Report Share Posted May 16, 2010 ok, have mine fully constructed, but 5v checkpoints are a hair low, 4.15v... this something i should be worried about? Quote Link to comment Share on other sites More sharing options...
space6oy Posted May 16, 2010 Author Report Share Posted May 16, 2010 went ahead & gave it a shot. powers up fine but isn't being recognized by the software. *sigh.* Quote Link to comment Share on other sites More sharing options...
Wilba Posted May 16, 2010 Report Share Posted May 16, 2010 To start with, 4.15V is too low.... the 5V regulator should be outputting much closer to 5V, at least 4.9V Check the voltage going into the 7805, that would be the pin not labelled with a 5V or 0V (ground) label. What is the 9V voltage like? I don't know what you mean by "recognized by the software". Do you mean MIOS Studio 2 is not detecting an attached MIDIbox? I'd say fix your voltage issue first, in case it is low voltage causing the MIDI to not work. Quote Link to comment Share on other sites More sharing options...
space6oy Posted May 16, 2010 Author Report Share Posted May 16, 2010 thanks wilba, will get on that tomorrow & report back. really appreciate the help, hope i get the lil' guy up & running! Quote Link to comment Share on other sites More sharing options...
space6oy Posted May 16, 2010 Author Report Share Posted May 16, 2010 oh also i actually masked off & spray painted my panels, worked just fine if you'd like to add that to the suggestions. did mine in metallic silver, will share a photo. Quote Link to comment Share on other sites More sharing options...
Wilba Posted May 16, 2010 Report Share Posted May 16, 2010 Do you mean spray painted the engravings? Quote Link to comment Share on other sites More sharing options...
space6oy Posted May 16, 2010 Author Report Share Posted May 16, 2010 yup. the power supply i'm using is 12v DC 300mA. Quote Link to comment Share on other sites More sharing options...
Wilba Posted May 17, 2010 Report Share Posted May 17, 2010 nicely done. 12V DC 300mA isn't enough. SIDs alone will draw 100mA each, even a miserly 100mA (of 250mA max) to the backlight and you're over budget :wink: Quote Link to comment Share on other sites More sharing options...
space6oy Posted May 17, 2010 Author Report Share Posted May 17, 2010 (edited) crazy, ok. how many mA would you suggest then? that was one of a few 12v DC supplies i happened to already have, but the highest mA, will have to pick up another. & nicely done to you as well, the housing & stacked PCB layout are both fantastic! one of these fit the bill? http://www.radioshack.com/product/index.jsp?productId=3875403&numProdsPerPage=60&retainProdsInSession=1&y=9&x=10 http://www.radioshack.com/product/index.jsp?productId=3807944&numProdsPerPage=60&retainProdsInSession=1&y=9&x=10 http://www.radioshack.com/product/index.jsp?productId=3875404&numProdsPerPage=60&retainProdsInSession=1&y=9&x=10 Edited May 17, 2010 by space6oy Quote Link to comment Share on other sites More sharing options...
Wilba Posted May 17, 2010 Report Share Posted May 17, 2010 I can almost guarantee these are all switchmode not transformer. There's no way you can get 12V DC 2.5A out of a plugpack that small. You'll need to hunt around some more, or hope some of the builders local to you can help. Quote Link to comment Share on other sites More sharing options...
space6oy Posted May 17, 2010 Author Report Share Posted May 17, 2010 switchmode = adjustable settings? only 12v on jameco is only 500mA, & none i'm looking at on there or the shack describe the supplies as "regulated..." :unsure: http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&sub_attr_name=Output+Voltage+%28volts%29&position=1&productId=162996&catalogId=10001&refineType=2&refineValue=10+%3C%3D++%3C+50&app.products.maxperpage=15&storeId=10001&refine=1&history=an8m7igy%7CsubCategoryName%7EPower%2BSupplies%2B%2526%2BWall%2BAdapters%2B%252F%2BAC-to-DC%2BLinear%2BRegulated%2B%252F%2BWall%2BMount%5Ecategory%7E453530%5EcategoryName%7Ecat_4535%5EprodPage%7E15%5Epage%7ESEARCH%252BNAV&ddkey=http:ParametricXmlView Quote Link to comment Share on other sites More sharing options...
Wilba Posted May 18, 2010 Report Share Posted May 18, 2010 "switchmode" and "transformer" are the two types of plugpack internals. Switchmode will be noisy for sammichSID - you'll hear it in the audio. Most of the new plugpacks are switchmode, especially if they're light and high current... I'm pretty sure practically every mobile phone charger is now switchmode. Electronics stores should still stock the old "transformer" kind. Quote Link to comment Share on other sites More sharing options...
space6oy Posted May 18, 2010 Author Report Share Posted May 18, 2010 ok, so how many mA should i be going for? Quote Link to comment Share on other sites More sharing options...
Wilba Posted May 18, 2010 Report Share Posted May 18, 2010 12V AC 500mA works. If using unregulated, any higher than 1000mA (1A) is too much, input voltage would be too high because the current load is much lower than the rating. If it's regulated, it doesn't matter if the current rating is high, as voltage will be constant. Quote Link to comment Share on other sites More sharing options...
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