AudioNervosa

Electro Stimulation Ward => Signals and Noise => Topic started by: S Clark on January 12, 2020, 03:37:45 PM

Title: Shielded cables for SUT?
Post by: S Clark on January 12, 2020, 03:37:45 PM
I have a step up transformer that has been loaned to me for quite some time, but it's incredibly picky about where it is located.  If it's next to nearly anything, it hums very loudly.  When move to a chair in front of the system, it's pretty quiet. But every IC cable I have is non shielded.  Is this likely to be the problem?  If so, what the shielded IC cables are you guys using?  Should I just get a Blue Jeans cheapy to see if this is the problem, or look for a recommended used cable?
Title: Re: Shielded cables for SUT?
Post by: Folsom on January 12, 2020, 03:56:02 PM
I would try some cheapies first to find out. I can't see inside it so I'm not sure exactly what is going on with it. Grounding is slightly different with these than something else because the ground for the TT is (or should only be) connected to the preamp. You are extending a shield. Where as your preamp relative to your amplifier is very different since you can ground out noise to the preamp so it never makes it to the amp.

Pics of the SUT?
Title: Re: Shielded cables for SUT?
Post by: S Clark on January 12, 2020, 04:15:52 PM

Pics of the SUT?
Wouldn't do much good.  It's a one off that Rim over at AC loaned me a couple of years ago.  It began life as some kind of multiple coil-multiple step up, but has been stripped to a single 18:1.  Basically coils in an aluminum box. 
Title: Re: Shielded cables for SUT?
Post by: Folsom on January 12, 2020, 04:40:18 PM
Ok but I can't see it's grounding configuration... Bust out the multimeter. See what is grounded and how.
Title: Re: Shielded cables for SUT?
Post by: S Clark on January 12, 2020, 05:08:47 PM
Ah,  tell you what, I've got dinner guest showing up any minute, but tomorrow I'll take the case off and get the meter on it.  I'll get a photo also.
Title: Re: Shielded cables for SUT?
Post by: Folsom on January 12, 2020, 05:34:17 PM
Ah,  tell you what, I've got dinner guest showing up any minute, but tomorrow I'll take the case off and get the meter on it.  I'll get a photo also.

Sounds good