Yet another transformer orientation question

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Hey all,

I read a bunch of the existing threads and yet was not able to find a conclusive answer.
With both PT and OPT vertical/upright, 90deg orientation to each other is understood.

I have ordered a PT from ISO and theirs is horizontal/laydown while my OPT's are the more common upright.

With the short side of the PT towards the OPT, is the correct orientation option A, or option B (attached photo).

Thanks!
 

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Circling back to this, would appreciate feedback if there is a preference to either of these layouts.
-Dimensions are 16"x11.5"
-This is for a headphone amplifier. Volume and headphone jack are in the front right.
-Power transformer is similar to the one pictured.
-Bottom left is tomchr's 21st Maida Regulator
-Top plate will sit on top of wooden base and prefer all parts on top plate.
-RCA connectors are top right next to OPT

Generally, I prefer option 2. Centers of all transformers are aligned on-top and (unless I'm mistaken), the center axis of the PT is not "pointing" at the tubes or OPT's. The only thing I dislike about this is the position of the IEC inlet.

Option 1 puts the IEC inlet in a better position, but I'm not sure if the rotation of the PT is now an issue. Although, in this layout the PT is even further away from the OPT's.

Thoughts?
 

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Using a wood cabinet is fine.
However, it's good to line it with alumium, such as the flashing used for roofs, etc.
You want a total electrical shielding, top, bottom, all sides, to eliminate any stray hum in the system.
Of course these aluminum pieces must be electrically connected as one.
 
How 'bout keeping the orientation of the PT the same as Option 1, but moving it toward the front by the depth of the IEC? So the IEC would have the location of Option 2, but without rotating the PT to make room for it.

Just a thought.

Ooh, and +1 to wiseoldtech . And remember, aluminum 'skins over' immediately, so when you go to connect the sides to the top, put a sharp-edged lockwasher (or some such) in the 'sandwich' to make sure you're cutting through the thin but durable oxide film.

Regards,
Rick
 
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How 'bout keeping the orientation of the PT the same as Option 1, but moving it toward the front by the depth of the IEC? So the IEC would have the location of Option 2, but without rotating the PT to make room for it.

Just a thought.

Ooh, and +1 to wiseoldtech . And remember, aluminum 'skins over' immediately, so when you go to connect the sides to the top, put a sharp-edged lockwasher (or some such) in the 'sandwich' to make sure you're cutting through the thin but durable oxide film.

Regards,
Rick


yeah Rick, those are "star lockwashers".
I use 'em all the time.
 
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Thanks all for the feedback.
I have made some progress and am going with a chassis that will allow me to put the RCA and IEC inlet in the back. So no issues regards those anymore.

Not sure though if there are any preferences with regards to the transformer orientation in Option 1 vs Option 2. FWIW, option 2 seems to be used much more often and looks to be a more "standard" layout
 
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Thanks all for the feedback.
I have made some progress and am going with a chassis that will allow me to put the RCA and IEC inlet in the back. So no issues regards those anymore.

Not sure though if there are any preferences with regards to the transformer orientation in Option 1 vs Option 2. FWIW, option 2 seems to be used much more often and looks to be a more "standard" layout




The Magnavox chassis that I rebuilt/upgraded/customized/etc., is dead silent, cranks out excellent sound, been using it for 15+ years now without an issue.
 

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Nice! That is the same as layout 2 I mention.

The reason why I am asking about this is because I am slightly concerned with the length of the PT secondary wires.
The connections in the PCB for the 5V heater and HV center tap are on the bottom left of the PCB.
With layout 2, my 120V AC wires are short to the rear, but the AC secondaries (HV CT and 5V heater and 6.3VCT are rather long wires to the PCB)
The DC wires from the HV reg are short though.

With layout 1, the 120V AC is slightly longer (which is fine), but the AC secondaries are much shorter and closer to the PCB.

So basically its a compromise between shorter secondary wiring, and transformer orientation...... I simply don't know which is better in this case
 
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Nice! That is the same as layout 2 I mention.

The reason why I am asking about this is because I am slightly concerned with the length of the PT secondary wires.
The connections in the PCB for the 5V heater and HV center tap are on the bottom left of the PCB.
With layout 2, my 120V AC wires are short to the rear, but the AC secondaries (HV CT and 5V heater and 6.3VCT are rather long wires to the PCB)
The DC wires from the HV reg are short though.

With layout 1, the 120V AC is slightly longer (which is fine), but the AC secondaries are much shorter and closer to the PCB.

So basically its a compromise between shorter secondary wiring, and transformer orientation...... I simply don't know which is better in this case


Let me make it simple for you.....
What you're saying about wiring length is of no issue - all you need do is to splice suitable extensions to the transformer, and shrink tubing over the splices.
It's really that simple.


Any wiring carrying AC should be twisted pairs, dressed close to the chassis, to eliminate hum.
 
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