ok so some update info for you guys/gals... i have the first re-make of the dc-dc power boards coming for the 808 systems.. thanks to the people whom looked over the board's i re-designed.. will be a few weeks i think.. before they get here.. will keep you posted.. also some one in the group has made a cad of the key stalk plunger to be 3d printed but on several try's i think they need to be resin printed as the fdm is not fine enough..
well dosen't time fly... it's been a bit since i have updated on here and if you have been on the facebook group you will see where i am up to with the 808's as of now... but fear not i am going to put it all on here too.. also going to do a repair part on rust removal and re-plating parts in nickel. so stay tuned.....
ok so from where i left off ...... what i did was in January..
well opened the SVI-808's today and the psu's have problems.. as i was expecting from the blog that he was writing.. so the next step is to go through to see where & what voltages are missing.. it uses a dual 16v ac power pack to a dc drop down board.. and its the normal 5+,5-,12+, 12- and ground so if its totally dead its and easy replacement option.
ok im looking for someone whom maybe able to help he out.. what i'm doing is remaking the DC power boards for the svi-808's as the quality is not good.. i have made the circuit in kicad and it checks out ok... i just need someone whom knows this stuff to look it over to make sure its ok.. thanks for any help.. and PM me if you would like to help out.. (sorted now thanks)
For sale 1 x SVI-808/818/838 DC-DC internal replacement Boards only.. re-designed as was not happy with the original quality ones. use all your existing parts or could help with some parts (regulators and diodes etc for extra) the Board's are $15 each + P&P
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Well got some more done on the 808 dc boards today.. and after finishing off had some issues and had to do 1 mod to the board.. the fab house didn't see i had put a ground through the 5v rail. but pass the inspection.. oh well... after that small fix it powered up fine.. just the 12v a little low.. but should be ok.. on power up the 808-SVI badged pc wood boot but had a blank screen.. so after trying a different screen i tried the 808-franken badged pc and that booted ok with the same screen.. so looking at the board the Yamaha chip looks a little crusty.. so maybe a clean and reflow.. will see.. the sound was not too good on the 808-sv so took the board out and it looks like the silver fish liked it more than the last owner,, lol.. so off it comes.. (need new one put in) so that's where I'm up to for now.. i did find the 808-franken pc had the ram card to take it to 640kb but it would be a little flakey at times so took it out.. and it seems ok now..
Well it is not too often i have to clean out cases like the SVI-808 pc.. i have put the bolts and din shield covers etc. in to a rust remover to soak, then i cleaned the case.. what a state it was in.. after that i did the main board. now I'm sure they have not looked that clean in a long time.. lol.. i also started rust treating the shields as well.. not sure if i will paint them or not.. also wonder if i should retro brite the case.... on the fence with that one.. also on cleaning i found what could be the problem with this board not showing on the screen.. the 16kh crystal has a broken leg... so will dig out one to replace it with.. and maybe the few electro caps that are on the board as well..
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