cajitastompboxes
New member
- Joined
- Sep 21, 2018
- Messages
- 4
Hi from Argentina, im working on an two channel YAMAHA Pm2000 rack, from channels strips of the original board.
So i was having noise crackling in both channels, and when the gain rotary switch bypass the NE80200 at -20db, the noise it goes, so im assuming that this OPAMP its faulty or noisy.
So i take one and degooped it (its no that hard because is silicon no epoxy), and make the photos, and clon version in express pcb, also a not so good schematic, i think its correct, but im lacking some technical abilities to find out where to start, to maybe resolve the crackling issue.
Y see four diodes and they have no markings, only a number 1, maybe they are simply 4148, doubt about they been zeners of some type.
So im posting the info in case of the curiosity of someone and also asking what can be changed to fix the opamp, or what can check first maybe.
What i already done is, the solder was brittle and old so i reflow everything.
Thanks i hope the pictures can be the help for someone else.
So i was having noise crackling in both channels, and when the gain rotary switch bypass the NE80200 at -20db, the noise it goes, so im assuming that this OPAMP its faulty or noisy.
So i take one and degooped it (its no that hard because is silicon no epoxy), and make the photos, and clon version in express pcb, also a not so good schematic, i think its correct, but im lacking some technical abilities to find out where to start, to maybe resolve the crackling issue.
Y see four diodes and they have no markings, only a number 1, maybe they are simply 4148, doubt about they been zeners of some type.
So im posting the info in case of the curiosity of someone and also asking what can be changed to fix the opamp, or what can check first maybe.
What i already done is, the solder was brittle and old so i reflow everything.
Thanks i hope the pictures can be the help for someone else.
