[RE-wrenches] Odd Outback FNDC/Mate issue

[William Miller]

Joel:

I am correcting you.  Twisting wires causes cancellation of RF 
energies.  This is true for wires that have RF energy on them that you wish 
to keep from emitting RF energy or wires that do not have RF energy and you 
wish to prevent them from receiving RF energy.

Therefore, if one could twist battery cables tightly enough, one might 
reduce RF emitted from them.  This is not always practical for 4/0 cables, 
but is practical for small gauge sensor wires.

One of the best wires for rejecting RF energy is your garden variety Cat 5 
cable.  We use it to send audio signals (I volunteer as a technician for 
entertainment events) for up to 2,000 feet and in the same cable is a ring 
line with 100 VAC at 20 cycles.  There is no cross talk.  What also makes 
this possible is the audio signals are a true balanced signal --  every 
electron that moves one direction causes another electron to move the other 
direction in the other cable.  This allows "common mode rejection."  This 
is cancellation of any induced signal.  The induced signal causes electrons 
to move in the same direction at the same time in both wires of the 
pair.  This equi-direction signal can be easily removed by a transformer or 
matched linear amplifiers.

I go into this detail only in hopes engineers with Outback might see if 
these principals might be applied to future designs.

William Miller


At 09:17 AM 3/28/2009, you wrote:

>Please correct me if I am wrong, but I thought that twisting wires creates 
>a magnetic field and increases radio frequency interference.

Please note new e-mail address and domain:

William Miller
Miller Solar
Voice :805-438-5600     Fax: 805-438-4607
email: william at millersolar.com
http://millersolar.com
License No. C-10-773985
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