I recall a memory board that was wirewraped we this used on a 8080 sbc micro controller, The power supply was the problem the wire all went in the same direction across the board, we removed the power and rewired the power at 900 with a larger gauge wire from 35g to 22g {if my memory is ok... no pun here} This and loads of caps sorted the noise problem. also some people run all the wraps in a cableform the noise from other wire are unbelivable, I liked to wire point to point myself. ----- Original Message ----- From: Chris Eddy To: Sent: Wednesday, March 22, 2000 8:20 PM Subject: Re: (ot) noisy wire-wrapped project | Jane; | | I will put a case of beer on power supply routing on your prototype. | | All audio and digital grounds must be kept seperate. Return them | seperately to the central power point with a big filter cap at the | center. Never mix ana and digi together. | (the secret is not wire gauge, but the fact that digital switch currents | are passing through the same ground traces that you are using for your | analog circuits). | | Also, add the obligatory 0.1 mic caps everywhere. But they will not | make up for ground layout. | | Chris Eddy | | Jane Ifurung wrote: | | > Helpppp! I had my circuit wire-wrapped and found out | > that it's so noisy. My project is a voice multiplexer | > and I have subscriber line interface circuit(SLIC), | > codec, relays, transformer, and logic ICs. I did not | > use bigger wires for the power supplies. | > | > Any idea what caused this and ways how to reduce the | > noise? Any site that would be useful? | > | > I used vector board and no ground plane. | > | > Hoping for your answers. | > | > ===== | > *~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~ | > Jane Ifurung | > UP Diliman, Quezon City | > 920-5301 loc 5854 | > (632)731-3545 | > jifurung@eee.upd.edu.ph | > *~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~ | > | > __________________________________________________ | > Do You Yahoo!? | > Talk to your friends online with Yahoo! Messenger. | > http://im.yahoo.com |