MX-1000 C549 Mystery

Crazeehorse

Active Member
While replacing the binding posts on my MX-1000 I noticed something strange. C549 ont the binding post board has a polar 47uF 50v cap in place but the manual calls for a bi-polar 4.7uF 50v cap. The circuit board is printed such that it should have a bi-polar cap there as well. Any thoughts?
 
While replacing the binding posts on my MX-1000 I noticed something strange. C549 ont the binding post board has a polar 47uF 50v cap in place but the manual calls for a bi-polar 4.7uF 50v cap. The circuit board is printed such that it should have a bi-polar cap there as well. Any thoughts?

Go with whats installed!
 
Read the third bullet statement right below the schematic view of the cap.

"Diagram subject to change without notice"
 
I wouldn't.. But its your project. Be a waste of and "ES". Its in the protect circuit. No sonic benefit what so ever. I'd go with a " KL" .
 
Go with what is there.
What is your serial number?
These amps have had a few changes to circuitry without any official service bulletins.
More on this later...taking off with the plane...
 
K, back on line..the plane has WiFi and I have a few hrs to kill....LOL

Abt the serial number... The 02xxx+ would have had the changes already made. The 01xxx would have had the bi-polar 4.7uf. The changes were made for a reason. I have seen a 01xxxx very messed up. Yamaha went ahead and improved the protection circuit mainly as well as other areas of the amp.... Like I said, I am not aware of any service bulletins for this amp, but I am certain abt the changes.

Like Avionic said, don't waste that ES, you'll find a better use for it somewhere else.

If you post a photo of the sub-boards / amp boards, I will be able to point you to that other areas of where the circuitry changes were made.
 
Resurrecting a Zombie thread in case someone else runs into the C549 issue and pulls it before noting the orientation of the correct 47uf 50V Polar cap. The negative mark on the cap faces the outside of the case! If it's backwards it will be stuck in protection.
 
Back
Top Bottom