Hi there ,Maybe someone has experience with this problem.My father is building an organ with 38 tubes/pipes.I like to "feed" them with µcontroller ,problem is that i need 38 outputs .Second problem are the magnetic DC valves .I thought about 2/2 valves that are payable Thanks , Johan

You have an interesting project there...

What microcontroller are you using? You need one with 38 outputs right? Maybe you could use an I/O expander. As for the DC magnetic valves, I never have used them before...

I have a stk500.Maybe i should buy the expandboard.Is there no other or better solution?Thanks ,Johan

I would recommend just buying a I/O Expander. Here are some links:

IOX (I/O Expander) Chip:
http://www.njqrp.org/iox/index.html

Maxim I/O Exanders:
http://www.maxim-ic.com/quick_view2.cfm/qv_pk/4412

As for a 2/2 electromagnetic valve, it's less complex than a 3/2 valve. Where are you buying it from?

If you are going to use a uC for the project you can easily handle 38 outputs. Once you know the type of power needed for the valves a controller board should be no problem. You can control the valves using transistors, relays, etc.... and to get the 38 outputs a serial shift register (or two, three) could be used. A uC should be able to handle the task without much trouble at all.

Ok,thanks all for the usefull replies.Than a still have the problem of buying 38 magnetic valves (2/2). 1/4" would be sufficent for the air suply to each pipe.But as it is still a hobby it must be payable Any idee ?I googled but it's all seems expencive (38 X ) Greetings , Johan

Well, you could try eBay.

Or you could search using Froogle: http://froogle.google.com/froogle?q=DC+mag...=en&btnG=Search

Hope this helps....

We are ebayers but nothing found.This froogle thing looks OK.Maybe buy from Chinese sellers?!?Thanks ,Johan

I was wondering johan, did you have success in finding the right valves?

I did n't surch this week because i had lots of work.Have jou find anything interesting on the net?

What do you think of building a electronic synthesizer? It's possible to build one, even without a use of a microcontroller....

Ok, you made me currious !!shoot!!!!

If you're new into these type of stuff, you can get a nice kit from here:
http://www.paia.com/
or
http://www.ladyada.net/make/x0xb0x/


Here's some links to help you out:
http://www.musicfromouterspace.com/
http://www.abacom.com/~ivanohe/synth/ivanohe1e.html
http://www.oldcrows.net/~patchell/
http://home.swipnet.se/cfmd/synths/friends/stopp/

This one was in a Nuts and Volts issue:
http://www.musicfromouterspace.com/analogs...H/soundlab.html

Hope you have fun building a synthesizer. They're really cool.