Megadrum by Japi - Documentation / Pictures -

[japi]

I see your point, thanks for the suggestions Troubleshooting is so time consuming..

I'm building dmitri's two board scheme, maybe it's time to give it a try to Synthex's all in one 2.5 to see what comes up. I don't know, maybe i'm too frustrated today and tomorrow I feel better
Better go to see a movie to clear my mind a little hehe

Thanksssssss

[gastric]

For some reason I thought you did build the V2.5 board.

[japi]

No, if you see the links to my pictures in this thread you'll see i was doing the digital board
After watching wall-e I don't know if I feel better or worse

[japi]

UPDATE

Well, the old board was frozen and I will not continue working on it, it began to malfunction and after trying to troubleshoot it without luck, I got frustrated
If you want to see the last pictures I took of it, here are some (including a prototipe analog board to make tests)

http://www.japiwebcam.com.ar/japi/megad ... oard_dead/

Now that I have the 4851's (thanks Synthex for sending those) I will try to build Synthex v2.5 all in one
Yesterday I lost 4 hours trying to print the inputs pcb to scale. The main board printed right away as I used the pdf's made by other users that are in this forum. So I printed, transferred to pcb, etched. The transfer was good but in the input pcb I lost some of the bottom part. I just used a marker to redraw that part. Certaintly not cute but effective. I also corrected two shorts: there was one in the main board, in the lines that comes from the 4851's (pins a,b,c). There should be all a, all b and all c together, but not abc together. Mine was abc together, due to the thin copper lines. I just scrapped it (hope that's the word) to fix the short. There was another in the inputs board, don't remember wich one, but same cause, same fix.

Today (sunday) I made the holes and cut the inputs pcb.
Picures here

http://www.japiwebcam.com.ar/japi/megadrum/08-newboard/

[gastric]

I'm curious to hear some details as to why you thought the first board was dead and unrepairable?

[japi]

Mainly because:

1) Some leads of the circuit are broken, some are very important like usb
2) Now I have the 4851 and can do the all in one
3) Lack of interest/knowledge to troubleshoot it. Got frustrated, and almost had no comments here about it, besides you. I'm no electronic expert, all you see in the pictures done has been learnt in the past days. Starting over with the all in one was the decision to give myself another try. If I fail again I'll end up buying a commercial product and realize that i'm not up to the task

[dmitri]

...and almost had no comments here about it...

I think this statement is unfair.

[japi]

I'm not blaming anyone Dmitri, I just think that being successfull or not in this project depends basically of two persons (you and synthex), that have the knowledge to help others

I thank very much the efforts you both do, but I feel frustrated when problems comes and I'm "alone". That's why I said that

Sorry if I bothered you, didn't wanted to

[japi]

Progress from today..

http://www.japiwebcam.com.ar/japi/megad ... /index.php

Pictures 12 and 13

Gastric I wonder why your resistors are the same size in your build. Mine are different sizes :O

[japi]

I have a little problem, i was soldering the usb header and it ocurred to me to check continuity. I have continuity between vcc and gnd all over the board
I think theres a short somewhere. Where are common places of fault ? I'm looking with a magnifier but couldn't find anything suspicious yet