Hey Graham, OK - well, it's reassuring (sort of) to hear that they are supposed to sound similar (some, like ambulance, sound appropriately crazy). "There is a surface mount cap on the big synth board “ Ah - do you mean that there is a cap on the other side of the big synth board (MA1M?) I only changed the caps that were on the top side. Please clarify. I was hoping not to have to take that off... For the record, my guitar did not work until I recapped the top of the synth board. I think in some of the tutorials it states that it will still work - but if the caps are corroded enough and go open then it kills the circuit. I was pretty careful to scrape off all corrosion. The hardest part was getting melted black plastic from those SMD mounts off. I used a hobby knife to scrape at them until they were clean. And I did test all connections. Everything has continuity where it should have it) and I do get six independent triggers. But I guess I’ll go through and hit everything again. I used through hole Nichicon PW electrolytics for all the polarized electrolytic SMD caps. it was quite easy to get them on once I had the pads clean. And there is plenty of room to lay them flat, so the double stacked board wasn’t an issue. ALSO - it’s nearly impossible for me to see where the test points are for the calibration (meaning the three “adjustments” on the adjustment page in the manual). Would you happen to have a color version of the schematic? Then I could at least see which side of the board the test points were on. I mean.. I can sort of guess, but… Would have been nice if Casio had labelled the test points on the boards. Oh well… best, DT > On Jun 24, 2015, at 12:48 AM, gmeredith1@... [casiocollectors] <casiocollectors@yahoogroups.com.au> wrote: > > > The synth sounds are generally louder than the guitar but not heaps louder. I suspect there is a component still to be replaced. Many of the onboard sounds do sound boring and the same - which is why people buy the cards to get more varied sounds. Probably even more similar if they're overdriven like yours. > > > > There is a surface mount cap on the big synth board - you'll need to replace this. Also check that you've done both sides of all the boards (I can't remember if there are some on the other side) > > One really big problem I had when I did mine was that when I replaced the caps I still had trouble. It ended up being that where the tracks were on the bottom of the board was corroded, and even after thinking that I'd cleaned the tracks before soldering in the new caps, there were bad connections still. I had to redo them. Check each cap leg and track with a multimeter for continuity of the solder joint (should read zero ohms if good). It took me ages to get it right. On some caps I had to connect them not at the track's pad but a bit further up by scratching the coating off the track and soldering it there. It was that bad - although it didn't actually look bad. > > Did you use tantalum through hole caps, or original surface mount caps? I used the original surface mount caps - big mistake and a pain in the neck to solder. Use tantalums if you can. > > Again, I think you have a bad solder joint somewhere. I had the distortion sound at one point until I redid all my cap joints. > > > Until you get the level and distortion issue sorted out, you won't be able to calibrate it. > > > > Keep trying and don't give up! You'll get it if you do. > > > > Cheers, Graham > > > > > > >
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Re: [casiocollectors] : PG-380 schematic
2015-06-23 by D T
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