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Partridge MC transformers (Part 2)

Designing the layout on a chassis can be difficult, but this is only a step-up device so should be easy.

Here are the raw parts:


Enclosure (mine is a Hammond 7" x 5" x 3")
2 Partridge mic transformers
4 RCA connectors
1 phono ground post
Hook up wire 

To put holes into my chassis, I used a stepped drill bit and a Greenlee chassis punch.


Morgan Jones recommends a chassis punch for any hole greater than 9 mm. I only wanted the top half of the Partridge cans to poke out, so I chose a 1-3/16" punch. These are easy to find cheap on eBay and usually come in sets like drill bits. To use the punch, first drill a 1/2" preliminary hole with the stepped drill bit.


Then attach the punch and tighten until you "snap" open a hole.


The hole is actually kind of smooth even without a file (I didn't have one available).


Both transformers attached now.


I subsequently took a break here and tried to remove old solder from the pins with solder wick/desoldering braid. What a pain.

Anyway, I didn't have a ruler, so I just eyeballed the RCA placements.


Looks ugly, but hopefully it'll sound OK after wiring it up and laying some shielding.


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