In article ,
"Ralph D." wrote:

Hi,

I need a cable (ideally about 20ft), stereo 3.5mm male/male, highly shielded
to connect my audio source to a transmitter across a room. This cable passes
many sources of interference, so the shielding is critical.

I would prefer to get it from Amazon so as to get it quick with Prime
(incredibly narrow window of free-time during a currently very busy
schedule) but would be OK with ordering from one of the Ham sites if
turnaround time is very good. I could not get a good search parameter on
Amazon that didn't turn up thousands of hits that I just don't have time to
sift through right now.

Any good cable with known good isolation would be good. I have ferrite
chokes I can use, but would prefer a cable of suitable quality that did not
need them (current cable is getting interference even with them as this is
not just run-of-the-mill 60cycle stuff).

Any good suggestions would be appreciated.

Look for a cable TV-coax (RG-6, maybe) that has a continuous foil shield.

Isaac

On 3/9/14 23:49 , isw wrote:
In article ,
"Ralph D." wrote:

Hi,

I need a cable (ideally about 20ft), stereo 3.5mm male/male, highly shielded
to connect my audio source to a transmitter across a room. This cable passes
many sources of interference, so the shielding is critical.

I would prefer to get it from Amazon so as to get it quick with Prime
(incredibly narrow window of free-time during a currently very busy
schedule) but would be OK with ordering from one of the Ham sites if
turnaround time is very good. I could not get a good search parameter on
Amazon that didn't turn up thousands of hits that I just don't have time to
sift through right now.

Any good cable with known good isolation would be good. I have ferrite
chokes I can use, but would prefer a cable of suitable quality that did not
need them (current cable is getting interference even with them as this is
not just run-of-the-mill 60cycle stuff).

Any good suggestions would be appreciated.

Look for a cable TV-coax (RG-6, maybe) that has a continuous foil shield.

Isaac




For this application, you'd want a cable with at least a 95% braid shield.

A more effective solution would be to convert the audio to a balanced
line at one end, and then back to unbalanced at the other. Better CMRR.
Shielded twisted pair, here, will get the job done.

On Mon, 10 Mar 2014 08:24:12 -0700, D. Peter Maus
wrote:

...snip...
For this application, you'd want a cable with at least a 95% braid
shield.

A more effective solution would be to convert the audio to a balanced
line at one end, and then back to unbalanced at the other. Better CMRR.
Shielded twisted pair, here, will get the job done.




might look into high quality cabling like Belden 1800F
John Woodgate in UK and I worked together to extensively analyze that
cabling and exploring 'weaknesses', have LTspice models and he has a lot
of application data.