EP5 cable connectors (Amphenol)

[ed_]

Hi folks... this is what happens when a lampy starts messing with audio kit:

 

I'm making up some EP5 cables. To cut a long story short, the female cable connector is very straightforward to assemble: put the back shell on the cable, solder, slide shell over insert, apply cable grip and crucially, insert one screw in the body of the connector to retain the plastic bit with all the contacts. Same way some cheap XLRs work. Said screw is supplied with the connector and where it goes is clear as day. The Amphenol assembly drawing illustrates well:

 

http://www.amphenol.com.au/drawing/128_Ser...128199-000X.pdf

 

However, the male cable connector is a different story. The metal backshell is not keyed (i.e. rotationally symmetric) so the insert is free to twist. Although there is a hole in the shell, there is no corresponding hole in the insert, nor is a screw supplied. So all that stops the contacts from falling out the front is the solder joints. I'm clearly doing something very wrong here. How is it retained? Have I got dodgy EP5 connectors here? Anyone who's done this before will either know the answer off the top of their head and make me look stupid, or confirm my suspicion that the connector is duff.

 

However, the Amphenol assembly drawing makes it clear there is no screw: http://www.amphenol.com.au/drawing/126_Ser...126036-000X.pdf - is it just a poor design?

 

Any help much appreciated, I would call Amphenol but they're shut until the morning and I was planning on a night of soldering...

 

Edit: fixed link

[boswell]

Both drawings you refer to are the same! :blink:

[ed_]

Both drawings you refer to are the same! :blink:

 

Link updated.

[boswell]

Not used the Amphenol before but is the screw that holds the screen lug meant to go thro' the hole in the backshell?

That's the only thing I can see from the drawing

HTH but prob not!! :blink:

[Lion Tamer]

I may be wrong here as I have never used these connectors but have used many other connector types in the past.

 

1. I think that if you turn the insert round so that you can see the chassis connection tag you will find a screw.

2. Put the insert into the chassis so that the above screw lines up with the hole in the chassis.

3. Insert a screwdriver through and turn the screw clockwise (it may be anticlockwise but I think they are reverse thread from memory) as you would normally - you should find that the screw actually comes up so that the head sits in the hole in the chassis and locks the connector together.

 

This may seem a counter intuitive way of doing it but it does stop you loosing the screw if it undoes itself.

 

I may be wrong but that is what it looks like from the drawing (I have come across a similar thing with some XLR connectors).

 

Hope that helps

 

Jem

[ed_]

3. Insert a screwdriver through and turn the screw clockwise (it may be anticlockwise but I think they are reverse thread from memory) as you would normally - you should find that the screw actually comes up so that the head sits in the hole in the chassis and locks the connector together.

 

You're right, there is a screw, but it's threaded normally. I thought of this and tried it, but the screw is not long enough and falls out of the insert before meeting the shell. I just don't know why the hole is in the shell (and it lines up with the screw) but the screw is too short (and loosening it also causes the grounding tag to become loose).

 

A concurrent post has been automatically merged from this point on.

 

Update: Solved. The screw that holds the chassis solder tag is the right one, and yes you need to unscrew it. However on my sample I had to flip the solder tag upside down (as the bit the screw goes in dips slightly, and reversing it makes it raise slightly) which is enough to make the screw engage the shell.

 

Thanks Jem - and also Amphenol, who being Australian, are answering the phone this time of day!

[Rob_Beech]

Come to this one a bit late, so my answer is useless now as you've already found it but pleased you got it sorted, there are a few XLR's like that, infact IIRC they're Amphenol ones. It's not a bad design, just seems a bit odd.

 

<insert joke about it being the opposite way on and it being the right way in Australia here>