BradHK
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I am going through the wiring of my 1954 M-75 Aristocrat and have a couple questions that somebody with a more extensive knowledge of guitar wiring hopefully can answer. From what I can tell, everything is original from 1954. I have drawn out a wiring diagram but need to take my hand drawn diagram and put it into an electric format. Any software packages or website tools for this? The general routing of the wiring is that the wiring from the pickups goes first to the three way selector switch, then to the tone pots, then to the volume pots and then to the output jack. My main question is around the use of caps.
The first question is that there is a 002 MFD cap at the three way selector switch between the bridge pickup lug and the ground lug. I would guess this would darken the tone of this pickup all of the time. Is that correct?
My second question is around the use of caps at the tone pots. The signal from the selector switch goes to a four lug circuit board beside the tone pot (Pictures below). The pickup signal goes to the far left lug in the photo of the pot from the back. In addition to the pickup lead there are two caps attached to this lug. A 022 MFD cap is wired between this left lug and the far right lug then goes to the tone pot center lug. This part (other than the circuit board use) is normal to me and the tone pot controls the use of this cap. The lug on the circuit board second to the right is just a ground. The lug on the circuit board second to the left is the signal going to the volume pot then to the output jack. This Circuit board lug is connected to the far lug on the left (pickup signal from the selector switch) by a cap. That would mean that all of my pickup signal is going through a cap. This was verified by a multimeter. The use of a cap to send the full pickup signal through (rather than bleed off high frequencies to ground) is new to me. Has anybody seen this before? Any thoughts?
The last question is whether anybody can identify the brand and size of the small brown cap in my photo with the yellow, purple and orange bands. I know the bands represent the value but I have not been able to locate a reference sheet for this brand cap.
The tone pot in the photo below is for the bridge pickup. The neck pickup does not have a cap at the selector switch, it is wired with two caps and the circuit board just like the bridge pickup but both of the caps for the neck pickup are 006 MFD. Based upon the use of caps it appears that this would make the bridge pickup darker than the neck. That seems backwards to me. I am unable to read the pot values so these could be different for the neck and bridge.
The volume and tone pot location in the guitar also appear backwards related to the pickups. The volume pots are on the top toward the center line of the guitar. The bridge pickup pots are on the left and the neck pickup pots are on the right. I can rotate the harness 90 degrees clockwise and I would have the two volume pots to the left and the neck would be on top like a “normal” four knob configuration. My guess is that was the intent and whoever installed the harness at the factory messed up. I will rotate when I reinstall the harness.
Any insight or thoughts appreciated!
The first question is that there is a 002 MFD cap at the three way selector switch between the bridge pickup lug and the ground lug. I would guess this would darken the tone of this pickup all of the time. Is that correct?
My second question is around the use of caps at the tone pots. The signal from the selector switch goes to a four lug circuit board beside the tone pot (Pictures below). The pickup signal goes to the far left lug in the photo of the pot from the back. In addition to the pickup lead there are two caps attached to this lug. A 022 MFD cap is wired between this left lug and the far right lug then goes to the tone pot center lug. This part (other than the circuit board use) is normal to me and the tone pot controls the use of this cap. The lug on the circuit board second to the right is just a ground. The lug on the circuit board second to the left is the signal going to the volume pot then to the output jack. This Circuit board lug is connected to the far lug on the left (pickup signal from the selector switch) by a cap. That would mean that all of my pickup signal is going through a cap. This was verified by a multimeter. The use of a cap to send the full pickup signal through (rather than bleed off high frequencies to ground) is new to me. Has anybody seen this before? Any thoughts?
The last question is whether anybody can identify the brand and size of the small brown cap in my photo with the yellow, purple and orange bands. I know the bands represent the value but I have not been able to locate a reference sheet for this brand cap.
The tone pot in the photo below is for the bridge pickup. The neck pickup does not have a cap at the selector switch, it is wired with two caps and the circuit board just like the bridge pickup but both of the caps for the neck pickup are 006 MFD. Based upon the use of caps it appears that this would make the bridge pickup darker than the neck. That seems backwards to me. I am unable to read the pot values so these could be different for the neck and bridge.
The volume and tone pot location in the guitar also appear backwards related to the pickups. The volume pots are on the top toward the center line of the guitar. The bridge pickup pots are on the left and the neck pickup pots are on the right. I can rotate the harness 90 degrees clockwise and I would have the two volume pots to the left and the neck would be on top like a “normal” four knob configuration. My guess is that was the intent and whoever installed the harness at the factory messed up. I will rotate when I reinstall the harness.
Any insight or thoughts appreciated!