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HighFidelityGuy
03-06-2010, 20:50
I've recently started work on a linear regulated DC supply for the Beresford Caiman and I've decided to use an XLR connector for the DC output as I like them. I'm going to use some spare balanced microphone cable as the DC power cable. I was originally going to use the two internal wires for the DC and leave the shield unconnected but I've just started wondering if there would be any point connecting this to the chassis ground inside the PSU. I'd then leave the shield unconnected at the DAC end.

Does anyone have any thoughts on whether I should do this or not? Is it actually likely to provide any sort of benefit in preventing interference from getting in or out?

Thanks. :)
DSJR
03-06-2010, 22:04
It can't do any harm I reckon...
Barry
03-06-2010, 22:07
+1

At worst it will do no harm, at best it could prevent RFI getting onto the supply wires and causing mischief.

Regards
leo
03-06-2010, 22:12
worth doing if its ran near any unshielded signal leads or anything sensitive to pick up
HighFidelityGuy
03-06-2010, 22:26
Thanks for the replies!
I'll definitely do it.

Cheers! :)
sponge
04-06-2010, 08:38
I've recently started work on a linear regulated DC supply for the Beresford Caiman and I've decided to use an XLR connector for the DC output as I like them. I'm going to use some spare balanced microphone cable as the DC power cable. I was originally going to use the two internal wires for the DC and leave the shield unconnected but I've just started wondering if there would be any point connecting this to the chassis ground inside the PSU. I'd then leave the shield unconnected at the DAC end.

Does anyone have any thoughts on whether I should do this or not? Is it actually likely to provide any sort of benefit in preventing interference from getting in or out?

Thanks. :)

I've just done the very same thing on a linear I have just built (not for a Beresford though). Only difference is that I have wired directly to the regulator output and run the screened cable through a strain relief grommet which saves a couple of soldered joints and a mechanical connector.

Just make sure the screen is ONLY connected to earth at the PSU end.

Ken
lovejoy
04-06-2010, 14:57
I used one set of twisted pairs of a run of CAT5 cable for my PSU -> Caiman lead. The twisted pairs make for very good noise cancellation and it has worked a treat.