Crawls Backward (When Alarmed)

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Finishing the MIM 50s Stratocaster Upgrades

Now I'll get back to the Main Event, which is finishing up my MIM 50s Strat.

I have the new Don Mare Super Sport pickups installed, along with a new 5-way CRL swich and new volume and tone pots.  I'm also wiring up a Fralin blender circuit.  I have one on the Surfcaster, too, so I figured 'what the heck.'

You can see the hardware installed on top of a nice new aluminum pickguard shield.  Hopefully the shield, combined with the copper shielding I did to the body will cut down hum.

One of the keys to cutting down hum in a Strat is to ground everything to one point.  In the e-leck-tron-icks world, this is known as a "star ground."  If a circuit is grounded in multiple points, it's likely there will be 'ground loops' - points where current can literally circle between multiple grounds.  The result is hum in the output.

My star ground is just a terminal screwed into the guitar's control cavity.  I'll run the pickup ground leads, the output ground, and the grounds from the pots together and ground them here.

Check this out.  These are the capacitors I'm going to use.  They're Russian paper-in-oil (aka PIO) caps, and they have a reputation for nice detailed output.  I'm not convinced they will make a difference in this application, but I have 'em so here we go!

If you do a search on that big auction site on the Interweb, you'll see a lot of Russian PIO caps.  These are not all alike - these are K40Y-9s.  In my research, these were mentioned as being some of the "good" ones.  They sure look cool.

The cap on the left is an .033 uF - I'm using that for the main tone cap. 

I have the other two caps - 1000 pf - wired in parallel with a 220K resistor to make a 'treble bleed' circuit.  The caps total 2000 pf connnected this way.

If you're a geetar player and you've experienced that loss of treble when you roll the guitar's volume pot down, this is one solution.  It doesn't let the treble 'bleed' off. 

The values are not exact - these are a starting point.  If you experiment with this - do just that - experiment with the values.

Here we have the finished wiring. 

The green arrow points to the treble bleed circuit.  It's wired across the 'hot' and center leads of the volume pot.  I taped it up so nothing can short it out.

The blue arrow points to the .033 uF tone cap.  Fender originally used a .1 (super bassy), then went to an .047, and 'modern' Strats use an .022.  I'm starting with this value to see how I like it.

The yellow arrow is a terminal where I connected all the grounds.  The other end of this lead goes to the main ground in the control cavity.

Finally, the grey wire at the top of the picture is a shielded cable for the output.  If you use shielded cable, remember to ground the shield only at one end - otherwise you'll have a ground loop.

Here's the output jack - you can see where the cable runs through the body and connects to it.

It's a good idea to test your wiring before you button it all up.  You can plug the guitar in, and gently tap each pickup with a screwdriver and see if you have output and the switching works as you expect.

I still need to get some shots of the completed guitar - those are forthcoming.

 
 
 
 

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