Push-pull "Switchblade" mid booster preamp...

[mistermikev]

so yawn... yest another push-pull preamp layout from mike v... I know.  Just figured I'd share... another variation on a mid booster based on popular internet schem. 

NOTE: need to wire in some resistors across lugs 1/2 and 2/3 to turn a 250k(or 100k) pot into a 50k pot depending on what is available (100k if 100k or 62k if 250k).

 

[mistermikev]

BladePreamp_V1.3.pdf

for the record and in case anyone wants to try this I made some changes(new version above) and verified this version tonight.  There are a few small changes/notes I would make regarding a build:

1) pretty std practice but resistors first, then ic mount, then there were a couple parts I mounted on the back of the pcb since they would be close to the push/pull.  the diode for instance (make sure to orient correctly or you won't have power).  Also the .0033uF cap - you could bend it flat and it's really close but I just mounted it on the back.  finally, the 4.7uF cap - I used tantalum and bent it away from the push/pull.

2) I couldn't find acceptable pcb mount push pull pot so I used a std lug 25ok linear.  I used a set of 62k resistors and wired them directly to the pot lugs connecting together in the middle... I used the extra lead from each resistor to mount the pot to the board.  I drilled bigger holes for the dpdt part of the switch and this allowed the std lugs to push right in.

3) the ic is really close to the push/pull... I actually bent one of the tabs on the push/pull downward to give just enough clearance to sneak the chip in but with more patience it probably would have fit fine.

4) I had to trim off the bottom row on the board (by the pot) as my top was 1/4" thick.  More than likely this wouldn't be a problem in the std strat pickguard but if you need to you can sand off that bottom row (ground) and simply run a wire from bridging the top left corder to reconnect the left side.