If you are into guitar amp building or the likes, you will possibly hear the terms drop in or flat, vertical, horizontal mount tossed around when it comes to transformer layout styles. Here is a little enlightenment together with 1:1 scale pdfs to help you in your designs when it comes to using Mercury Magnetics transformers.
When it comes to mount a power or output transformer to the chassis, there are several ways to do this depending on your available chassis space. If you look in old Fender chassis you will find that the power transformers were mounted vertically, with only a hole in the chassis where the wires would pass through. Marshall on the other hand, had a lot of drop in power transformers where the chassis had to be modified to house one side of the winding. There are generally no ups or downs for either styles. It really comes down to a logical positioning of the transformer in your chassis design so it would not impede with other electronic components.
Mercury Magnetics has a simple system of identifying their transformer mounting styles. When you order, keep in mind the following characteristics:
Mounting Method: horizontal, vertical or flat.
Footprint: the center hole to center hole dimensions.
Layout: 2 or 4 hole.
Following are the available mounting styles from Mercury Magnetics transformers:
4 HOLE MOUNTING STYLE
Horizontal Mount – the transformer’s bobbin sits in horizontal position:
Vertical Mount – the transformer’s bobbin sits in vertical position:
Flat Mount – the transformer’s laminations (steel sheets that make up the transformer’s iron core) are parallel to the chassis:
2 HOLE A-FRAME MOUNTING STYLE
Usually this style is used to mount chokes or smaller transformers (like reverb transformers, etc.) where mass is not that critical so a 2 hole mount would suffice to keep it in place.
A-Frame Horizontal Mount – the bobbin is in horizontal position:
A-Frame Vertical Mount – the bobbin is in vertical position:
- Endbells (caps that cover the bobbins and laminations) are optional. Not all transformers and chokes can be fitted with endbells.
- A-Frame Mounts are standardized.
- 4-Hole Mount transformers mount in several ways, including L-brackets and endbells with “feet” (stamped and folded, one-piece).