By maintaining a higher average-to-peak ratio. In broadcasting, we call it
"masking", and it has been used by AM broadcasters for years to cover up
audio from co-channel stations that interfere with them in the fringe
coverage areas. The first company to popularize that was CBS Labs with
their famous Audimax and Volumax processors of the 1960's, which were
advertised as being able to bring entire new communities into a station's
coverage area, and it really did!
FM stations use heavy processing to cover up noise, especially with a stereo
signal since the SN 'hit' a stereo signal has to take when decoding the L-R
38 kHz DSB subcarrier is on the order of 17 dB. That type processing became
popular when engineers found out they could increase average modulation with
a set of back-to-back diodes across the composite output of the stereo
generator. A better, more sophisticated method gained popularity with the
Modulation Sciences CP-803 Composite Clipper. Today, Telos-Omnia has taken
the technology to the max with their Omnia 6ex processor. It has around 100
adjustable parameters that can be controlled locally or via an Internet
connection, so I can sit in my car with a laptop and adjust the box in a
normal listener environment.
Another poster said "I always work the cleanest clearest signal first...".
If he can't hear the signal, he won't work it.
There seems to be a notion that intelligibility decreases when processing
increases, and there is some truth to that when it's done poorly. But done
right, you can create a "wall of sound" that busts through pile-ups. With
SSB, more RF equals a bigger wall! That's why the Orion "talk power"
problem is a real issue.
Ron N6IE
www.N6IE.com
(Formerly N6AHA)
----- Original Message -----
From: "Barry Gross" <barry.n1eu@gmail.com>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Saturday, December 23, 2006 4:46 AM
Subject: Re: [TenTec] Orion 1 & 2 "Talk Power" problem
Please indulge me - I want to understand the point. How does one
create the QRM that keeps weaker stations from being heard, other than
having a strong signal (max ERP at optimal arrival angle, properly
compressed/equalized audio)?
73,
Barry N1EU
On 12/23/06, Ron Castro <ronc@sonic.net> wrote:
Simple...in keeps weaker stations from being heard under you.
> On 12/22/06, Ron Castro <ronc@sonic.net> wrote:
>> That may be true, but creating the QRM needed to get out in front is
>> fair
>> play, even though on the surface, it may not sound that way.
>
> How does "creating QRM" help one "get out in front"? (seriously, I
> don't get this and I've played in my share of pileups)
>
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