The AM Forum

This is an odd one...

A coworker has a Rickenbacker Electro Spanish "Electric" Guitar made in 1935 and it has one of those funky old style pickups. I looks like someone may have changed the volume control pot at some point, but we are not sure. The pot has one of the 3-terminals on the end cut off and the way it is wired sort of looks similar to what you would do in a tone control configuration, but without the capacitor.

I searched around the web and found this:

"This entire unit is then mounted into the Bakelite cavity, and is height-adjustable by the twisting of two knurled, spring-loaded nuts. This height adjustment is, essentially, a slant adjustment that changes the relative distance of the pole pieces to the strings. The pole pieces are graduated in height from flush at the treble side to a .056" elevation at the bass end. The combined effects of low magnetic pull in an opposing magnetic field, graduated pole pieces, and nonmagnetic hardware make this pickup a masterpiece in design for its time."

What we are trying to figure out is if this funky volume control wiring is correct or if someone did just replace the pot and wire it wrong.

Has anyone had any experience with these old guitar pickups?


(http://2.bp.blogspot.com/_BBUxvfcVq68/S1LFq6oKBzI/AAAAAAAAA8Y/mzATNBfdm1s/s200/modelb1.JPG)

Sounds like it is now wired as a shunt deal, dropping the voltage & impedance simultaneously.  Rather than a potentiometer, that is.

Probably worth enough dinero that it ought to go to a pro for the original/correct way.

Did you see this site while looking around? Probably did. Looks like the one you are talking about toward the bottom of the front page.
 Since they started in 1931 I would think this is a museum piece no matter what non-original control might have been installed. There is a "contact" tab on the page, I'll bet they can give you all the info you need.

http://www.rickenbacker.com/history_early.asp

Post a jpeg of the part itself??

Also contact Buzzy at www.larkstreetmusic.com - he is a very experienced dealer and restorer of old guitars, probably has had his hands on one of these...

                       _-_-bear

standard old pot, pin looks broken off... or never there...

           _-_-bear

Edit: oddly enough as shown the addition of the wire from the bottom of the pot to the lower leg will not change the operation, except as a taper... this is supposed to adjust the volume??  Odd way to do things... sure this works and is right??

Maybe it wasn't a volume control. It may have been a tone control as wired. With out a ground it would only vary the audio a smalle amount.

Fred

replace pot - add missing ground wire...

maybe a small cap between the wiper and top end to keep the tone (highs) up as the pot is turned down
(sometimes in series with a resistor). Looks like the lug is broken off from the pix...

Not much to think about here...

Carbon pots have been around a while...

                        _-_-bear

I wouldn't touch it move it as it's found.

Maybe if he went to the Rickenbacker website and contacted them direct they could tell him exactly what should be in there. It's a piece of their history. I would bet that they'd be glad to help him. Why mess with a relic.
Of course it's his baby and his call but this might take his playing enjoyment to a new level.

Xactly..why mess with a relic, who owned it are they still alive touch base with the maker it doesn't hurt to ask....but just to decide through any old audio pot in there
isn't contributing to the classic sense of the unit.

ah well...