1 Octive is Out

[sneed]

On my old 1986 Yamaha PF-80 weighted electric piano, the 2nd lowest octive of keys went out suddenly. Everything elese works fine. Any ideas?

 

[happyrat1]

Probably a dirty connector or a leaky capacitor.

Most likely oxidation on a keyboard connector, but at that age the capacitors are surely drying out.

DIY repair at your own risk.

Gary

 

[sneed]

The octive came back suddenly. Clearly this is an intermittent problem.

 

[happyrat1]

Loose or dirty connection. The problem will likely return.

 

[sneed]

So today the lower octave of keys is still working, but the 2nd to highest octave of keys is now out!

 

[happyrat1]

Dirty connectors.

 

[happyrat1]

Look. Do you feel confident enough to take it apart and remove the connectors, clean them, and reconnect them without bending any pins and reassemble the entire unit without creating any new problems for yourself or not?

There's plenty of instructional youtube videos on the subject and my first (and only) tip is to thoroughly document the entire disassembly with video or still pics.

But if you're not up to it, take it to a tech for $125 an hour.

The diagnosis is not going to change. A loose or dirty internal connector.

Gary

 

[Biggles]

So today the lower octave of keys is still working, but the 2nd to highest octave of keys is now out!

Is English your first language or do you have to run the replies through the translator?

You have been given the response as to the likely cause.

Others here including myself will offer the same advice.

So move on, get it repaired or buy a new keyboard.

Clicking the LIKE on Happyrat1’s replies would at least show some appreciation for the time he has taken to type the responses and for his advice.

 

[sneed]

I've opened the unit several times and repaired a few issues successfully. In doing so I have also disconnected and reconnected all wires and ribbon cables and sprayed a small amount of contact cleaner on them. I even tested the keys with the piano powered up and opened to see if manipulating the wires and cables affected any of the keys but saw no results.

 

[happyrat1]

Like I said, there is a lack of continuity affecting single banks of keys.

Pull out your scope and start tracing signals.

On a 40 yr old board, electrolytic caps are suspect.

 

[happyrat1]

Also with all that opening and closing, inspect the solder joints for cold flows and cracking.

 

[sneed]

Fixed it! Thanks happyrat1!

 

[happyrat1]