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previous: zachary vex the dole, and magicians -- 8/16/2000 9:54 AM view thread

Encapsulated circuits...?

8/29/2000 6:59 AM
Steve A.
Encapsulated circuits...?
Zachary:  
 
    Perhaps this has come up in a different thread, but to protect your designs why don't you just encapsulate the circuits in epoxy or casting resin? A friend of mine had gotten a Sea Moon "Funk Machine" back in the early 70's, which was a combination envelope follower/wah pedal apparently produced by a hippie commune in Northern California. I had never heard anything like it and popped the bottom panel off to look at the circuit (not that it would have meant anything to me...) Alas, there was a large block of casting resin in the middle with several leads coming out... :(  
 
    I don't like the idea of globbing silicone over the circuit boards in a tube amp, but with FX pedals it might be an acceptable measure to take to protect your designs. The cost of producing the board itself is very small compared to all of your other operating expenses and if you had to replace the board for any defective pedals that were returned, I do not believe it would be any more expensive than having to deal with copycat clones...  
 
    While an owner of one of your pedals might let a techie friend look inside and trace out the circuit, I really doubt that he would let his friend to destroy his pedal by cutting into the casting resin... A dedicated cloner would have to buy one of your pedals (Hey- that would be one more sale!) and even then he would probably destroy the board in the process of removing it from the resin...  
 
    To further complicate things, you could remove the markings from at least some of the components and use your own private color codes to keep track of which part is which. R.G. has an article on his site which mentions other tactics used by builders to keep their designs secure.  
 
    I don't like the idea of encapsulating or potting a circuit board in a tube amp because it makes the inevitable maintenance and repairs much more difficult (if not impossible) to perform. If you were to encapsulate your boards, you would need to keep replacements available, which you might ship out as needed to your network of trusted dealers to expedite repairs. You might consider offering a lifetime parts only warranty for the encapsulated boards (isn't it usually the pots, switches and jacks that go bad with your pedals? Or do you use IC's which might possibly fail more than discrete semiconductors?)  
 
Steve Ahola  
 
P.S. Your point about not POSTING your schematics is well taken. You never know who may be lurking in the background here whose intentions are not honorable. Sharing knowledge between trusted friends is one thing; passing out proprietary information to anyone who might wander by is something else...  
 
P.P.S. In your "library" you wouldn't have a schematic for one of those Funk Machines, would you? :D

 
Replies:
aron Personally I HATE epoxy on circuit ... -- 8/29/2000 8:35 AM
R.G. I'll post the Funk Machine schemati... -- 8/30/2000 10:01 PM