Older Kent armstrong hotrail pickup wiring.

musicalstash

Any  ideas on the wiring layout on an older Kent armstrong hotrail style pickup. 

It has red - bare  - white - black - blue wires 

Guessing the red goes to the pickup selector and the barevback of the pots but not too sure if the others. 

The newer Kent armstrong pickups have a different layout. 

Just want  to wire it as a standard "full" humbucker. 

Any help would be appreciated. 

Funkfingers

Use a resistance meter to identify which of the four conductors connects to which end of which coil bobbin. 

My guess is red hot/output, black to white, blue and bare to ground.

BillDL

Going purely from memory of wiring an old Kent Armstrong and a Rainbow (very early Kent Armstrong brand) humbucker into a hollowbody guitar I believe the wiring code was a bit counterintuitive in that where we quite often expect red to be hot it wasn't:

• White = Hot (to switch or to input lug of volume pot depending on wiring scheme of guitar)
• Black and Bare wire = Ground (solder to back of pot or to common ground connection)
• Blue and Red = Solder together and insulate for series continuity link between coils for standard humbucker functionality.

My memory may be wrong though, so you would be best to check with a meter, but you might be able to get a more immediate impression of whether this is correct by temporarily twisting the red and blue together, taping the black and bare to the sleeve of a guitar cable's plug, and taping the white to the tip of the plug.  If the "thunk" when you tap the pickup lightly with a screwdriver is of the expected loudness and much the same as another humbucker equipped guitar plugged in and the pickup tapped then it's probably correct.

musicalstash

Thanks... Just had a meter on the pickup and it comes up a

Bare to red 5.56
Bare to black 0
Bare to white 
Bare to blue  0.02

the only other reading I can get is 

Red to blue 5.56

Not too sure but maybe an issue with the pickup?

BillDL

On a healthy humbucker you should only get a significant DC Resistance reading in the region of what you have seen (i.e. for one coil) between two of those wires as long as they are all separated out and none are making contact with each other.

You have established that Red is one end of one of the coils and Blue is the other end of that same coil, and it's reading somewhere in the region of half the expected DC Resistance if both coils were linked together in series.

You should therefore expect to see roughly the same DC Resistance for the other coil across the White and the covered Black wire.  Try this again and make sure you weren't just getting a dodgy connection with a probe, and that you have the digital meter set to DC Resistance up to 20K, which is often the lowest you have on many multimeters.

A bare uninsulated wire is normally connected to the metal frame of the pickup and would therefore be connected to ground / earth.  You shouldn't normally get a DC Resistance reading like that when connecting the bare wire to any of the others.  Try doing a continuity test if your multimeter has this setting.  Touch the bare wire with a probe and then touch each of the others in turn noting if it beeps on any of the contacts.

Something isn't right, but I'm not a pickup or electronics expert, so that diagnosis is best left to one of the experts.

ICBM

The bare wire should have no reading to any of the others - if it does there's a short somewhere. This might not be catastrophic depending on where it is - if it's in the pickup and can't be fixed it just means that wire has to be grounded. If it's in the cable it could be as simple as cutting it shorter, since it's most likely at the end which has been heated when soldering it to the back of a pot.

The first thing I would do is strip about an inch more of the outer sleeving from the cable and make sure all the wires are definitely separated from each other, then try the resistance readings again. Ideally you should have two pairs of 5.56K each.

impmann

http://kentarmstrong.com/schematics/KA_Wiring_Instructions.pdf