Noob question - adjusting dual IF transformer cores (Pioneer TX-6500)

[MWH901]

Pictured is the T5 dual IF transformer on the Pioneer TX-6500 tuner. Adjusting the lower core centers the meter; adjusting the upper core minimizes distortion.

Question: is the gray hex-shaped hole in the middle used to adjust the lower core?

If so, which tool is used to adjust the upper core? If not, what do you use to reach through to adjust the lower core?

Thanks in advance...
-Mike

 

[Punker X]

I always find it easier to adjust from the bottom of the board. Most of the time there is a hole in the board to access the core. If not you can use correct alignment tool and adjust from the top. I find this more difficult. The hex doesn't catch as well, and you can change the top when trying to remove it. I have resorted to removing the transformer, drilling a hole in the board.

 

[gadget73]

usually you can just push the tool through the upper core and into the lower one, but if the spacing is dumb or the alignment of the flats is not right it won't actually get all the way through so they can adjust independently. Should be the same size hex for both cores though. Have to use one of those tools with the hex on the end and a smaller shank behind it, and those tend to be a bit flexy.

but yeah, honestly easier to flip the board over and go from each end most of the time.

 

[MWH901]

I always find it easier to adjust from the bottom of the board. Most of the time there is a hole in the board to access the core. If not you can use correct alignment tool and adjust from the top. I find this more difficult. The hex doesn't catch as well, and you can change the top when trying to remove it. I have resorted to removing the transformer, drilling a hole in the board.

I popped off the bottom cover and there is a hole in the bottom of the board. Thanks so much for the tip!

 

[MWH901]

usually you can just push the tool through the upper core and into the lower one, but if the spacing is dumb or the alignment of the flats is not right it won't actually get all the way through so they can adjust independently. Should be the same size hex for both cores though. Have to use one of those tools with the hex on the end and a smaller shank behind it, and those tend to be a bit flexy.

but yeah, honestly easier to flip the board over and go from each end most of the time.

Confirmed same-size hex on both cores. I will access the lower one from the bottom as you suggest. Thanks for the advice!