www.megadrum.info

Hi all!
I have a boring question for you ... I'm about to to build up my PCB for megadrum (with ferric chloride, printer ink and so on...) and, first, I would like to know if you advise me to do it or to renounce (the result is not good...; you will fail...). Im not skilled with this kind of operation but I would like to learn.

Then, the schematics given use the PIC18F2550 and the BAT85. I think that many of us are trying so save time and money so maybe preferred to use the IC 4851 (to avoid diodes and resistors) and to use PIC18F13K50 (because it's cheaper).

If I'm right, I wanted to know if there is anybody skilled who can update the image to print on copper and use for PCB, making this changes (4851 and PIC18F13K50). I'm asking just because for the moment I'm not able to do it by myself, and maybe for one who can use the program it takes just an hour or two.

If I'm mistaking on times needed excuse me, I don't want to waste your time, just tell me and I will try to learn to use KiKad and drew the schematics (or find somebody else who can teach me XD)

Thanks anyway

Ale.A wrote:Hi all!
I have a boring question for you ... I'm about to to build up my PCB for megadrum (with ferric chloride, printer ink and so on...) and, first, I would like to know if you advise me to do it or to renounce (the result is not good...; you will fail...). Im not skilled with this kind of operation but I would like to learn.

Then, the schematics given use the PIC18F2550 and the BAT85. I think that many of us are trying so save time and money so maybe preferred to use the IC 4851 (to avoid diodes and resistors) and to use PIC18F13K50 (because it's cheaper

At the moment you won't be able to program either PIC18F13K50 or PIC18F14K50 with WinPic or any other program using a JDM type programmer so it is no go with the ICSP cable.

If I'm right, I wanted to know if there is anybody skilled who can update the image to print on copper and use for PCB, making this changes (4851 and PIC18F13K50). I'm asking just because for the moment I'm not able to do it by myself, and maybe for one who can use the program it takes just an hour or two.

It takes more than a couple of hours to design a board like this.

If I'm mistaking on times needed excuse me, I don't want to waste your time, just tell me and I will try to learn to use KiKad and drew the schematics (or find somebody else who can teach me XD)

The schematic is already drawn in the KiCad format and I posted it along with the PCB. If you want to use 4851's with this PCB, just don't solder BAT diodes and replace current limiting resistors with wire jumpers.

If you are not experienced in electronics, I would suggest you just go with what is there. A couple more diodes is only a few more seconds of soldering. I have successfully done a PCB and have a working unit, but for a first etch, this will not be the easiest PCB to make. Even having done it before, I had to try several times before I got all of the traces to take (still had to touch up a few).

Not trying to discourage you, but just giving you a heads up. Most are finding Synthex's kit to be a very straightforward and reasonably simple build.

Good luck with whichever way you go.

Ok, thank you very much for advices, and... perfect I will jump over diodes and resistors... but... wait... "we have a bigger problem now"

May I substitute the PIC18f550 with the PIC18F13K50?... It seems I can't
If yes, I should change the pcb, but how can I program it? nothing similar to pic18f550? I can't use the icsp cable so can't pass through megadrum... so what did you mean with alternative to pic18f550?

So now what I have to do? trash my PIC18F13K50 and buy the suggested pic18f550?
(I've already bought all the components and foolishly tried to save few useless euros)

Sorry for all this ignorance that makes you waste time...

Ale.A wrote:Ok, thank you very much for advices, and... perfect I will jump over diodes and resistors... but... wait... "we have a bigger problem now"

You don't jump over diodes, you just exclude them. Read carefully what I advised.

May I substitute the PIC18f550 with the PIC18F13K50?... It seems I can't
If yes, I should change the pcb, but how can I program it? nothing similar to pic18f550? I can't use the icsp cable so can't pass through megadrum... so what did you mean with alternative to pic18f550?

To program PIC18F13K50 you need a proper programmer like PicKit2, ICD2 and etc.

So now what I have to do? trash my PIC18F13K50 and buy the suggested pic18f550?
(I've already bought all the components and foolishly tried to save few useless euros)

If you can program PIC18F13K50 - use it.

Making a PCB is not that hard, but it may take a couple of tries to get the hang of it. You might want to make some inputs boards or something as practice before trying this one.

I would order a complete kit. This way you can start building when you get your package.
I didn't order a complete kit and got sick of looking for parts.

Many thanks to all for the answers...

I will practice and try to build the pcb just because I like to learn always new things.
By the way, if I create the pcb, is there anyway non destructive to check if it works? I mean have I to solder the holes (using wires) to check if current flows correctly through ways? Or the multimeter are able to connect the holes not "dirting" with solders?

I will buy the pic18f550, because, if I'm not wrong, I will be able to program it directly through megadrum, with no additional physical support like PicKit2, just using a free software on pc.
This is true for atmega as well, right?

I already got sick looking for all the components XD so now I can't buy the complete kit... Also because as I said, DIY for me is not just saving money and assemble part already done... It's been hard to understand everything but I have also learned many things about electronic

Just try to understand me... I'm a young graduating engineer... I've got my alienations XD

Thanks

Ale.A wrote:I will buy the pic18f550, because, if I'm not wrong, I will be able to program it directly through megadrum, with no additional physical support like PicKit2, just using a free software on pc.
This is true for atmega as well, right?

This is from the front page where the main features are listed:

No need for an expensive programmer. Programming is done via a simple cable.

^^' I read that page many times and everytime I understand something more... and also how good this project is
thank you