Talk:Bias
From Academic Kids
In my opinion the passage:
An example of bias is having an Americo-centric point of view (the point of view of an American, in particular one from the US), or similar for another country.
is unfair. Whilst I am no sympathiser with America (I doubt they need any), using any particular country in an example of bias is bias itself.
I think references to particular countries should be deleted from this article.
- Funnily the first section seems to be quite Americo-centric since it mentions only American examples :) Fornadan 20:05, 29 Apr 2005 (UTC)
I deleted the following para:
"Bias is used in modulation to create a carrier wave from the oscillator. In FM, the bias is quite high, and defines the center frequency. In AM, the bias is only as high as the peak of the normal audio input signal, and defines the average amplitude of the RF output signal."
As someone who has designed many AM and FM transmitter circuits, this is more or less rubbish. It may refer to one particular type of design, and one I'm not especially familar with at that - but it is not a statement that is in any way generally true. The first sentence in particular is simply wrong in any interpretation I can make of it. An oscillator produces a carrier wave, period. It does not need "bias" to make it produce a carrier wave - it just does. A certain design of oscillator may include an element that changes the frequency of the oscillator, and is sensitive to voltage - a varicap diode for example - in such a circuit, a bias voltage would be usually needed to establish the center frequency, and an AC signal applied here would cause frequency modulation - but this is all a particular implementation detail, it does not belong in this article. This use of the term bias is covered by the para that is already there. The mention of AM in this para is also erroneous, I have no idea what the author was trying to say. The AM modulators I've designed don't fit this picture, and I don't think my designs are especially wacky. In any case it's another implementation detail that doesn't belong in this article. Stay focused, people!
I should also say I have some issues with the para that talks about DBS receivers. I feel it is also very specific to a caertain kind of design, as well as being not terribly clearly written. However, I don't know enough about the subject to simply remove it, so I've left it in. GRAHAMUK 23:47, 27 Sep 2003 (UTC)
Etymology important for understanding English word "bias"
I would like to suggest that perhaps there should be a better definition on bias here since bias is taken to mean several things depending on which European root it was ultimately taken from. I would think that the English bias is ultimately an amalgimation of the two.
A) The Ancient Greek bia (pronounced Vi-a), means (when applied):
1. strength, force, opression, violence.
B) The Middle French biais (pronounced ), means:
2. a slant, an angle,
C) In English Bias means:
3 : a line diagonal to the grain of a fabric; especially : a line at a 45° angle to the selvage often utilized in the cutting of garments for smoother fit 4 a : a peculiarity in the shape of a bowl that causes it to swerve when rolled on the green b : the tendency of a bowl to swerve; also : the impulse causing this tendency c : the swerve of the bowl 5 a : BENT, TENDENCY b : an inclination of temperament or outlook; especially : a personal and sometimes unreasoned judgment : PREJUDICE c : an instance of such prejudice d (1) : deviation of the expected value of a statistical estimate from the quantity it estimates (2) : systematic error introduced into sampling or testing by selecting or encouraging one outcome or answer over others 6 a : a voltage applied to a device (as a transistor control electrode) to establish a reference level for operation b : a high-frequency voltage combined with an audio signal to reduce distortion in tape recording
Taken from (dictionary.com) & Pocket Greek dictionary - Langenscheidt.by Dr Karl Feyerbend.
--JamesTheJust 07:26, 7 Jun 2005 (UTC)
