Best way to isolate non-isolated RCAs?

[Sherman]

I cut and drilled the top plate for my new project and am almost ready to fire up the soldering iron! But first a question.

One of the goals of this project was to try and work with what I had in the parts boxes and what was in the boxes were some uninsulated RCA jacks I'll use for inputs (only 2, I'll be using a "passive preamp" for source switching). I would prefer not having the input jacks "grounded" to the chassis. Does anyone have any good suggestions for isolating those 2 jacks or am I going to have to break down and purchase isolated jacks?

BTW the jacks mount from the outside with a 1/4" hole. My top plate is 1/8" aluminum so there isn't a ton of "extra" length sticking through.

Thanks for any ideas!

 

[SY]

There are a few ways to proceed. The method I use for a pair of RCAs is to drill the holes out to half an inch or so, then fashion an insulating backer board with 4 mounting holes for screws and two 1/4" holes for the RCA jacks. The plastic board can be unclad PCB or (if you want it to look fancier) some 1/8-3/16" Lucite. This isn't elegant, but it can be done with a minimum of tools.

 

[leadbelly]

Try grommets plus nylon washers fore and aft. The washers allow you to deform the grommets and make it tight.

 

[Jocko Homo]

I have a stash of insulating washers for a variety of jacks. E-mail me the dimension, and I'll look to see if any will work for you.

If that won't work...........

I have a stash of triple insulated jacks, in a vertical stack. Red,white, yellow style........the kind you see for video. You can have some if you are in a bind. No promise on how they sound, but they are insulated.


Jocko

 

[Enzo]

They make shoulder washers (T washers) for exactly that purpose. Otherwise I also make a larger hole then mount a piece of plexi behind it and mount the jacks to the plexi. Black plexi looks nice.

 

[sam9]

I used a piece of scrap PCB material. Mounted the RCA on that and then mounted the whole thing on the enclosure.. If it looks like it is going to be ugly even with near cuts, one possability is to first paint the PCB material a color that dosen't look like FR4 such as metalic silver.

 

[Sherman]

Thanks for all the replies!

My thoughts were sort of drifting in the direction of Sy's solution. I have a sheet of black Acrylic, a sheet of plexiglas and a sheet of 1/8" clear lexan. Should be a piece of cake to mount below the chassis.

I looked in the 'ol parts bin and it appears I have a dozen or so of these non-isolated RCAs so I may also look at the other solutions for future projects.

 

[Sherman]

I have a stash of insulating washers for a variety of jacks..

If that won't work...........

I have a stash of triple insulated jacks, in a vertical stack. Red,white, yellow style...

Thanks for the offer Jocko! I am constantly impressed at the generosity of people on this forum! I think I'm going to go with mounting the jacks in a piece of acrylic in keeping with the "do it with spare parts" theme.

So far the PTX is my only "real" purchase for this project. (I did also re-stock my resistor drawers but since those will also be used in future projects that doesn't count does it? 😀 )