Can't measure 325C64 bridge pickup

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Can't measure 325C64 bridge pickup

Postby (arrow201) » Fri Oct 18, 2013 2:16 pm

I just got my first 325C64, it was built in 2008. A friend of mine also has a 325C64, his was built in 2006.
We plugged in each of our guitars into the same amp, (one at a time). The middle/neck pickups put out the same volume
for both guitars, but his bridge put out more volume then mine. So we opened up mine, the middle/neck pickups measured
as expected, just over 7k BUT the bridge measures in the 9 megs area !?!?!? ...so, then we measured right at the pup assembly
where the wires are soldered on ...measured the same ????? Then we did the same with his and it has same type of reading !?!?
So, what's going on ? We used 2 different meters with the same results. Both guitars appear to work fine, though his bridge
is slightly louder than mine. It's like there's a cap right inside the pup assembly ...can someone shed a light of what might
be going on ?

Also, is the 325 schem at the RIC site: http://www.rickenbacker.com/pdfs/19512.pdf also applies to the 325C64 ?
If not, what are the differences.

Thanks !
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Re: Can't measure 325C64 bridge pickup

Postby (deaconblues) » Fri Oct 18, 2013 3:07 pm

There's no difference between the pickups. If you're reading 9 meg it's most likely a measurement problem.

There is a .0047 cap connected to the bridge pup in the wiring harness. It's common to take them out or jump them -- your friend's might have had that done?
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Re: Can't measure 325C64 bridge pickup

Postby (arrow201) » Fri Oct 18, 2013 3:22 pm

deaconblues wrote:There's no difference between the pickups. If you're reading 9 meg it must be a measurement problem.

There is a .0047 cap connected to the bridge pup in the wiring harness. It's common to take them out or jump them -- your friend's might have had that done?


Thank you for your reply. I don't see how it can be a measurement problem. we measured the middle and neck pups and they
are both in the 7k area as expected, took the pup right out of the body cavity and measured at where the 2 wires are soldered
at the pup, ~9 megs ....strange... unless, just by chance his is bad too, but they do work ...hmmmmmmm...

Yes, thank you for the cap info, I told my friend to check if his is still there.
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Re: Can't measure 325C64 bridge pickup

Postby (glen_l) » Fri Oct 18, 2013 7:39 pm

If you measure a stock 325c64 at the point where the neck and middle duo are soldered to the toggle switch, and with the toggle switch in the treble setting (to isolate them from the circuit) you should see approx 4k ohms. If you measure the point where the bridge pickup is soldered to the toggle switch, and with the toggle in the full bass setting, you should read approx 8k ohms.

The schematic you linked to is for a standard production 5 control, 3 pickup model such as 340, 345, 370, 375. There are differences with the reissue models like the c64, such as pot values and high pass capacitor in the treble path.
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Re: Can't measure 325C64 bridge pickup

Postby (arrow201) » Sat Oct 19, 2013 1:56 am

glen_l wrote:If you measure a stock 325c64 at the point where the neck and middle duo are soldered to the toggle switch, and with the toggle switch in the treble setting (to isolate them from the circuit) you should see approx 4k ohms. If you measure the point where the bridge pickup is soldered to the toggle switch, and with the toggle in the full bass setting, you should read approx 8k ohms.

The schematic you linked to is for a standard production 5 control, 3 pickup model such as 340, 345, 370, 375. There are differences with the reissue models like the c64, such as pot values and high pass capacitor in the treble path.


Glen thank you ...yes, that is what I did. The middle and the neck pup measure ~7.4k ...I didn't unsolder the pair, but my guess one is a true 7.4k and the other
is appearing open like the bridge ..so it reads 7.4k. I'm waiting for my friend to measure his middle and neck too to see if he gets the same.

Now, I also have a 325V63, all the pups are 12k, and everything measures as expected. The middle and neck being in parallel measure ~6k, the bridge measures ~12k.
I'm finding it strange with the readings I get from the C64, yet it appears to work fine......

Has anyone here with a stock 325C64 tried measuring the pups ?
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Re: Can't measure 325C64 bridge pickup

Postby (arrow201) » Sat Oct 19, 2013 11:54 pm

Bottom line is both the bridge and middle pups are bad~~~~~~
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Re: Can't measure 325C64 bridge pickup

Postby (glen_l) » Mon Jan 20, 2014 4:35 am

Yes, it sounds like at least one open circuit pickup
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