T901 sub transformer is open (lightning). I subbed in a 12V control transformer and it works as it should, but it's too big to mount in the confined area. The original transformer is a through the hole PC mount.
Yamaha part number is XA754001 obsolete as of 2008. Anyone have one to sell, or do they know of a close enough sub to fit the board for this model. I don't mind relocating foils or redrilling if I have to but customer prefers to keep it authentic if at all possible. Thanks.

On Mon, 24 Aug 2020 10:33:38 -0700 (PDT), "
wrote:

T901 sub transformer is open (lightning). I subbed in a 12V control transformer and it works as it should, but it's too big to mount in the confined area. The original transformer is a through the hole PC mount.
Yamaha part number is XA754001 obsolete as of 2008. Anyone have one to sell, or do they know of a close enough sub to fit the board for this model. I don't mind relocating foils or redrilling if I have to but customer prefers to keep it authentic if at all possible. Thanks.

What's the size and pin spacing/function?

RL

How abut a wall wart?

On 8/24/2020 1:33 PM, wrote:
T901 sub transformer is open (lightning). I subbed in a 12V control transformer and it works as it should, but it's too big to mount in the confined area. The original transformer is a through the hole PC mount.
Yamaha part number is XA754001 obsolete as of 2008. Anyone have one to sell, or do they know of a close enough sub to fit the board for this model. I don't mind relocating foils or redrilling if I have to but customer prefers to keep it authentic if at all possible. Thanks.

A lot of surround receivers have a 12V standby supply derived from a
small transformer on the board. If you look at the size of the one you
need, you might find something very close in an old surround receiver.
NAD, Arcam certainly used them, and I'm sure others as well.

You might also want to look at all of the pins on the old one, as you
might have an open thermal fuse. On some transformers it might be
possible to replace it. Sometimes it will take unwrapping the
transformer tape to find it. I would NOT suggest bypassing a thermal
fuse as a long term solution.

Regards,
Tim

On Tuesday, August 25, 2020 at 8:33:59 PM UTC-4, Tim Schwartz wrote:
On 8/24/2020 1:33 PM, wrote:
T901 sub transformer is open (lightning). I subbed in a 12V control transformer and it works as it should, but it's too big to mount in the confined area. The original transformer is a through the hole PC mount.
Yamaha part number is XA754001 obsolete as of 2008. Anyone have one to sell, or do they know of a close enough sub to fit the board for this model.. I don't mind relocating foils or redrilling if I have to but customer prefers to keep it authentic if at all possible. Thanks.

A lot of surround receivers have a 12V standby supply derived from a
small transformer on the board. If you look at the size of the one you
need, you might find something very close in an old surround receiver.
NAD, Arcam certainly used them, and I'm sure others as well.

You might also want to look at all of the pins on the old one, as you
might have an open thermal fuse. On some transformers it might be
possible to replace it. Sometimes it will take unwrapping the
transformer tape to find it. I would NOT suggest bypassing a thermal
fuse as a long term solution.

Regards,
Tim


Thanks for the advice fellas. For posterity, here's a solution by substitution, although the sub may be just as hard to find in the near future. By wasting far too much time, I discovered that the Sony 1-448-852-11 transformer is the same as the Yamaha XA754001. Same size, footprint, and even the same plastic foot snaps. Perfect fit with no mods required. All is well.

John