Pickup 20-73 not responding

[duskb]

I disassembled my '70 Rhodes last week to do a full cleaning (it was in really bad shape) and once we lit it up again keys 20-73 would not respond to any signal (contact or otherwise). The pickups worked before we took it apart but I find it hard to believe that we damaged all the pickups just by cleaning the piano (with it turned off mind you).

I guess we broke some wire somewhere?

Outside of that the only attention paid to the pickups was a mild scrubbing (with Scotchbrite) of the rust that had set in on pickups 1-15. These pickups still work though. We also had to readjust the left to right positioning of many of the pickups because the tines did not exactly line up with the pickups once we put everything back together (off by 1/4" in spots). Now these magnets are dead.

I spent some time looking at the diagram in the manual but I'm unsure what to look for around pickup 20 to determine where the fault would lie.

Any thoughts?

Dusk

[pianotuner steveo]

It sounds like it may be just a broken ground..can you post a picture of around pickup 20?

[Ben Bove]

I forget if your 1970 is wired the old-school way of the 60s pianos, where i believe they're like Christmas lights (one goes out they all go up).

You may want to just bridge over pickup #20 appropriately to test if you get signal beyond that pickup.  May have just died.

[duskb]

I forget if your 1970 is wired the old-school way of the 60s pianos, where i believe they're like Christmas lights (one goes out they all go up).

You may want to just bridge over pickup #20 appropriately to test if you get signal beyond that pickup.  May have just died.

A few things:

1. At first I thought brushing the plastic strip across the pickup tree may have damaged some wiring (though I don't recall seeing any wires snap off when we dusted it). I did notice that several leads were broken but they seemed to represent some sort of odd pattern (notes 1-19 exhibit this pattern and work fine).

2. I compared the pattern in the '70 manual to what I have and, of course, they don't match, at all (or I must not be reading it right). So a visual isn't very helpful without an accurate schematic.

3.  Since posting, I did take an alligator lead and jumped the top-rear pickup lead of 19 to the top front pickup lead of 20. All of the pickups respond to physical tapping however the output is REALLY low.

4. We also replaced the harp output signal cable (the RCA to 1/4" panel cable that terminates to the circuit board). The original was heavily corroded so we rebuilt using higher end Mogami. We also re-terminated the "piano to amp umbilical" since the original work was really bad. However our work is clean and we copied the pinout before rebuilding it. Food for thought though since this was part of the restoration process.

[Ben Bove]

Yes I assume your cable work was fine, my guess would be pickup related at least to try first.  Especially because 1-19 are in perfect working order.

Can you take a pic of your wiring scheme on the pickups starting from low to ~30?

[duskb]

Yes I assume your cable work was fine, my guess would be pickup related at least to try first.  Especially because 1-19 are in perfect working order.

Can you take a pic of your wiring scheme on the pickups starting from low to ~30?

I dont have one at the shop but I will get one and post them.

Dusk