Help with AMZ Mosfet Boost?

[ThisBrian]

I figured I'd try my hand at designing a PCB so I decided on the AMZ Mosfet Boost (a circuit I somehow screwed up on perfboard). Anyway, this is my first try and I didn't want to make a PCB and then have it not work so I was wondering if the more enlightened ones on the board could have a look over and see if I made any mistakes. It's a view of the copper side looking up, not a top view like you're looking in the pedal. R0 is a 2M2 pulldown, R7 is a 4k7 for the LED, and all the external hookup goes like so:

1. LED +
2. 9V
3. POT 1
4. POT 2
5. POT 3
6. 9V Jack Ground
7. Out Jack Ground
8. Out > Switch
9. LED - > Switch
10. IN > Switch
11. In Jack Ground



http://www.muzique.com/schem/mosfet.htm

Thanks

[danelectro]

http://www.generalguitargadgets.com/v2/index.php?option=displaypage&Itemid=162&op=page&SubMenu=

[ThisBrian]

I just revised the thread and design. Thanks again.

[ThisBrian]

Here is an alternate view, setup more like a normal parts layout. I'd really appreciate someone looking over this. I've looked it over and over and don't see anything wrong, but with my inexperience I'm sure I did something wrong.

[bwanasonic]

I didn't notice anything *wrong* on comparing it to the schem, but it's probably a good idea to mark the polarity of the electrolytic caps. Many find it convenient to use a trim for R2, so you might want to consider making room for one. I'm just getting into doing some PCB layouts, so I like to see different people's layout *style*. Good luck!

Kerry M

[ThisBrian]

Thanks. I marked the polarity. Using a trim for R2 sounds like a good idea too, I'll mess with that after I'm sure it'll work as it is.

[petemoore]

I just found R2 for a Mosfet Boost.
 I used a 100k pot with wires coming off of an outside lug, the other one coming off the wiper and remaining lug.
 I had a socket for the cap, and using the new test jig...a heavy box with jacks grounded and tips connected to wire/alligator clips, and a cardboard [diagonal cut] Mouser box on top with holes to jam pots in.
 I just stuck the 100k's leads into R2's socket, tested for sound, the set it so drain is at ~5,50v, then measure the undisturbed, removed pot, which measured 52k...actually I couldn't get the pot to hold the drain still at 5.50v, but very close and opted for a 56k...that brought the drain to ~5.46v...perfect enough for Rock and roll....one less pot used.