I just visited your page and find it very eye opening.
While I was aware of the effects to which you refer in your article on
“Transmission Lines at Audio Frequencies”, I had not seen the actual plots of
the responses before.
I am sure you are aware, but lots of sellers of very expensive audio cables
exploit the effects to which you refer, effects that are negligible (as you
state) at cable lengths less than 500 feet. These sellers contend the these
effects can be heard at 10 foot lengths and claim to have somehow compensated
for these effects in speaker and coax cable costing well over $500 per foot in
some cases.
This is in the same bin as the fellow’s device intended to “degauss” compact
disks, which are, of course, made of polycarbonate and Aluminum, both of which
are non-magnetic.
Read the following bunch of BS and you will know what I mean:
http://www.stereophile.com/content/cd-demagnetizing-1
<http://www.stereophile.com/content/cd-demagnetizing-1>
Regards,
Gary
> On Feb 21, 2016, at 8:48 PM, Jim Brown <k9yc@audiosystemsgroup.com> wrote:
>
> Let's get our words straight. First, a cable shield is a SHIELD first, and a
> circuit conductor second. It is NOT a "ground." For a shield to WORK, it MUST
> be connected directly to the shielding enclosure at both ends. That is a
> fundamental principle of shielding -- it must be continuous. Sadly, virtually
> all mfrs of ham gear fail to understand this, and tell us to do things that
> are simply WRONG.
>
> A cable shield that is NOT connected directly to the chassis at the point of
> entry is a CAUSE of hum, buzz, and RFI. Failure to follow that fundamental
> principle is known in the audio world as "the Pin One Problem," and was first
> exposed by Neil Muncy, ex-W3WJE (SK), in 1994.
>
> There are several tutorials on my website about this, and I urge all to study
> them.
> k9yc.com/publish.htm
>
> I will NOT waste my time by repeating that tutorial work here for those who
> are too lazy to read what I've already taken the time to write. :)
>
> 73, Jim K9YC
>
> On Sun,2/21/2016 3:37 PM, Sergio Escudero wrote:
>> Hi to all, the problem is the ground with the microphone (must) be separated
>> from the chassis ground, separate the mic capsule ground from the shield and
>> radio chassis see figure 2.4 of mic connection me and a local friend we
>> have wire several mic to the Orion2 , this will fix the RFI problem W4ESA
>
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