Hi, i have a transmitter 500w. I am using coaxial audio cable to give
modulation to the pll. I have many problems with R.F interferences from my
antenna or linear to pll. I believe that the audio cable collects R.F from
the antenna and transfers it to pll. I have read some articles about this
problem. the last one is this:
http://www.audiosystemsgroup.com/SAC0305Ferrites.pdf
I have read this:
<<*Avoid the use of shielded cables with a drain wire if the system will be
exposed to
strong RF below 10 MHz (AM broadcast, ham transmitters, light dimmers). Any
cable
with a drain wire will have significantly greater SCIN below about 10 MHz
than
a cable that uses a good braid shield. On the other hand, foil-shielded
cables provide
better shielding above 20 MHz. The best cable, if you can find it, is one
that
has both a foil and braid shield. Second best are those with very dense
braid
shields.
Both of these cable mechanisms are quite powerful -- simply switching from
zip
cord to twisted pair for loudspeaker wiring, or from foil/drain cable to a
good braid
cable, can easily reduce RFI by 20-30 dB if that is how the RF is getting
in.>>
*I can't understand it very well (my english are not very good). The editor
says to use or not coaxial cables for audio? What do you propose? *I*f i
must not use coaxial audio cable for modulation , what cable is most proper
to use for this purpose, to avoid R.F interference to my pll?
Thank you very much!
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