List of psychoactive plants - Revision history

93.109.103.42: /* Fabaceae (Leguminosae) */ just adding missing bullet-point

2015-01-02T06:05:01Z

Fabaceae (Leguminosae): just adding missing bullet-point

← Older revision		Revision as of 08:05, 2 January 2015
Line 1:		Line 1:
	~~Hi there,~~ I ~~am Felicidad Oquendo~~. I currently ~~reside~~ in ~~Alabama. Managing people is how she makes money~~ and ~~she will not alter it whenever quickly. What she enjoys performing is to perform croquet but she hasn~~'t ~~produced a dime with~~ it.<br><br>~~Feel free to surf to~~ my ~~webpage ::~~ [http://~~exitus.bplaced~~.net/index.php?~~mod~~=~~users~~&~~action~~=~~view~~&id=~~139~~ http://~~exitus.bplaced~~.net]		The writer is known as Wilber Pegues. What me and my family members adore is doing ballet but I've been using on new things lately. My day job is an invoicing officer but I've currently utilized for another one. For years he's been residing in Mississippi and he doesn't plan on changing it.<br><br>Stop by my weblog - real psychics ([http://findyourflirt.net/index.php?m=member_profile&p=profile&id=117823 http://findyourflirt.net/])

en>Sasata: Reverted edits by 94.101.164.117 (talk) to last version by Sasata

2014-02-04T15:43:20Z

Reverted edits by 94.101.164.117 (talk) to last version by Sasata

← Older revision		Revision as of 17:43, 4 February 2014
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	~~A '''frequency divider'''~~, ~~also called a '''clock divider''' or '''scaler''' or '''prescaler''', is a [[Electronic circuit\|circuit]] that takes an input signal of a [[frequency]], <math>f_{~~in~~}</math>, and generates an output signal of a frequency:~~		Hi there, I am Felicidad Oquendo. I currently reside in Alabama. Managing people is how she makes money and she will not alter it whenever quickly. What she enjoys performing is to perform croquet but she hasn't produced a dime with it.<br><br>Feel free to surf to my webpage :: [http://exitus.bplaced.net/index.php?mod=users&action=view&id=139 http://exitus.bplaced.net]

	~~:<math>~~
	~~f_{out} = \frac{f_{in}}{n}~~
	~~</math>~~

	~~where <math>n</math> is an integer~~. ~~[[Phase-locked loop]] [[frequency synthesizer]]s make use of frequency dividers to generate a frequency that~~ is ~~a multiple of a reference frequency. Frequency dividers can be implemented for both [[analog electronics\|analog]]~~ and ~~[[Digital data\|digital]] applications~~.

	~~== Analog dividers ==~~
	~~Analog frequency dividers are less common and used only at very high frequencies. Digital dividers implemented in modern IC technologies can work up~~ to ~~tens of GHz.{{citation needed\|date=April 2012}}~~

	~~===Regenerative frequency divider===~~
	~~A regenerative frequency divider, also known as~~ a [[Miller frequency divider]],<ref>{{cite journal\|author=R. L. Miller\|title=Fractional Frequency Generators Utilizing Regenerative Modulation\|journal=Proceedings of the IRE\|year=1939\|pages=446–457\|doi=10.1109/JRPROC.1939.228513\|volume=27\|issue=7}}
	~~</ref> mixes the input signal~~ with ~~the feedback signal from the mixer.~~
	~~[[File:RFD block digram~~.~~jpg\|center\|Regenerative frequency divider]]~~
	~~The feedback signal is~~ <~~math~~>~~f_{in}/2~~</math>. This produces sum and difference frequencies <math>f_{in}/2</math>, <math>3f_{in}/2</math> at the output of the mixer. A low pass filter removes the higher frequency and the <math>f_{in}/2</math> ~~frequency is amplified and fed back into mixer.~~

	~~===Injection-locked frequency divider===~~
	A free-running [[oscillator]] which has a small amount of a higher-frequency signal fed to it will tend to oscillate in step with the input signal. Such frequency dividers were essential in the development of [[television]].

	~~It operates similarly to an [[injection locked oscillator]]. In an injection locked frequency divider, the frequency of the input signal is a multiple (or fraction) of the~~ free~~-running frequency of the oscillator. While these frequency dividers tend~~ to ~~be lower power than broadband static (or flip-flop based) frequency dividers, the drawback is their low locking range. The ILFD locking range is inversely proportional~~ to the quality factor (Q) of the oscillator tank. In integrated circuit designs, this makes an ILFD sensitive to process variations. Care must be taken to ensure the tuning range of the driving circuit (for example, a voltage-controlled oscillator) must fall within the input locking range of the ILFD.

	~~== Digital dividers ==~~
	~~[[File~~:~~Frequency divider animation.gif\|thumb\|250px\|An animation of a frequency divider implemented with D flip-flops, counting from 0 to 7 in binary]]~~
	For power-of-2 integer division, a simple binary counter can be used, clocked by the input signal. The least-significant output bit alternates at 1/2 the rate of the input clock, the next bit at 1/4 the rate, the third bit at 1/8 the rate, etc. An arrangement of [[Flip-flop (electronics)\|flipflops]] are a classic method for integer-n division. Such division is frequency and phase coherent to the source over environmental variations including temperature. The easiest configuration is a series where each flip-flop is a divide-by-2. For a series of three of these, such system would be a divide-by-8. By adding additional logic gates to the chain of flip flops, other division ratios can be obtained. Integrated circuit logic families can provide a single chip solution for some common division ratios.

	Another popular circuit to divide a digital signal by an even integer multiple is a [[Johnson counter]]. This is a type of [[shift register]] network that is clocked by the input signal. The last register's complemented output is fed back to the first register's input. The output signal is derived from one or more of the register outputs. For example, a divide-by-6 divider can be constructed with a 3-register Johnson counter. The three valid values for each register are 000, 100, 110, 111, 011, and 001. This pattern repeats each time the network is clocked by the input signal. The output of each register is a f/6 square wave with 60° of phase shift between registers. Additional registers can be added to provide additional integer divisors.

	~~===Mixed signal division===~~
	~~(''Classification~~:~~'' ''[[Asynchronous circuit\|asynchronous]] [[sequential logic]]'')<br>~~
	An arrangement of [[D flip-flops]] are a classic method for integer-n division. Such division is frequency and phase coherent to the source over environmental variations including temperature. The easiest configuration is a series where each D flip-flop is a divide-by-2. For a series of three of these, such system would be a divide-by-8. More complicated configurations have been found that generate odd factors such as a divide-by-5. Standard, classic logic chips that implement this or similar frequency division functions include the 7456, 7457, 74292, and 74294. (see [[List of 7400 series integrated circuits]])

	~~== Fractional-n dividers ==~~
	~~{{Main\|Dual-modulus prescaler}}~~
	A fractional-n frequency synthesizer can be constructed using two integer dividers, a divide-by-n and a divide-by-(n + 1) frequency divider. With a modulus controller, n is toggled between the two values so that the [[voltage-controlled oscillator\|VCO]] alternates between one locked frequency and the other. The VCO stabilizes at a frequency that is the time average of the two locked frequencies. By varying the percentage of time the frequency divider spends at the two divider values, the frequency of the locked VCO can be selected with very fine granularity.

	~~=== Delta-sigma fractional-n synthesizers ===~~
	If the sequence of divide by n and divide by (n + 1) is periodic, spurious signals appear at the VCO output in addition to the desired frequency. Delta-sigma fractional-n dividers overcome this problem by randomizing the selection of n and (n + 1), while maintaining the time-averaged ratios.

	~~==See also==~~
	~~{{Portal\|Electronics}}~~
	*[[Phase-locked loop]]
	*[[Prescaler]]
	*[[Pulse-swallowing counter]] and [[pulse-swallowing divider]]

	~~==References==~~
	~~<references/>~~

	~~==External links==~~
	* [http://~~www~~.~~electronicproducts~~.~~com~~/~~ShowPage~~.~~asp~~?~~SECTION~~=~~3700~~&~~PRIMID~~=&~~FileName~~=~~FEBCON1.FEB2001 Delta-sigma fractional-n synthesizers]~~
	* [http://~~www.ece.uci~~.~~edu/~payam/RFD_ISCAS2005~~.~~pdf A Study of High Frequency Regenerative Frequency Dividers]~~

	~~[[Category:Electronic circuits]~~]

en>Sasata: Undid revision 593007104 by 65.9.175.167 (talk) rv incorrect: they have not been "mixed with other plants", these are different strains

2014-01-29T20:29:34Z

Undid revision 593007104 by 65.9.175.167 (talk) rv incorrect: they have not been "mixed with other plants", these are different strains

← Older revision		Revision as of 22:29, 29 January 2014
Line 1:		Line 1:
	~~Hi there~~, ~~I am Alyson Pomerleau~~ and ~~I think it seems fairly great when you say~~ it. The ~~favorite hobby~~ for ~~him~~ and ~~his kids~~ is ~~fashion and he~~'ll be ~~starting something else alongside~~ with it. ~~Invoicing~~ is ~~what I do~~. ~~Alaska~~ is ~~where I~~'~~ve always been residing.~~<br><br>~~Here is my web page;~~ [http://www.~~prograd~~.~~uff~~.br/~~novo~~/~~facts-about-growing-greater-organic-garden psychic love readings~~]		A '''frequency divider''', also called a '''clock divider''' or '''scaler''' or '''prescaler''', is a [[Electronic circuit\|circuit]] that takes an input signal of a [[frequency]], <math>f_{in}</math>, and generates an output signal of a frequency:

			:<math>
			f_{out} = \frac{f_{in}}{n}
			</math>

			where <math>n</math> is an integer. [[Phase-locked loop]] [[frequency synthesizer]]s make use of frequency dividers to generate a frequency that is a multiple of a reference frequency. Frequency dividers can be implemented for both [[analog electronics\|analog]] and [[Digital data\|digital]] applications.

			== Analog dividers ==
			Analog frequency dividers are less common and used only at very high frequencies. Digital dividers implemented in modern IC technologies can work up to tens of GHz.{{citation needed\|date=April 2012}}

			===Regenerative frequency divider===
			A regenerative frequency divider, also known as a [[Miller frequency divider]],<ref>{{cite journal\|author=R. L. Miller\|title=Fractional Frequency Generators Utilizing Regenerative Modulation\|journal=Proceedings of the IRE\|year=1939\|pages=446–457\|doi=10.1109/JRPROC.1939.228513\|volume=27\|issue=7}}
			</ref> mixes the input signal with the feedback signal from the mixer.
			[[File:RFD block digram.jpg\|center\|Regenerative frequency divider]]
			The feedback signal is <math>f_{in}/2</math>. This produces sum and difference frequencies <math>f_{in}/2</math>, <math>3f_{in}/2</math> at the output of the mixer. A low pass filter removes the higher frequency and the <math>f_{in}/2</math> frequency is amplified and fed back into mixer.

			===Injection-locked frequency divider===
			A free-running [[oscillator]] which has a small amount of a higher-frequency signal fed to it will tend to oscillate in step with the input signal. Such frequency dividers were essential in the development of [[television]].

			It operates similarly to an [[injection locked oscillator]]. In an injection locked frequency divider, the frequency of the input signal is a multiple (or fraction) of the free-running frequency of the oscillator. While these frequency dividers tend to be lower power than broadband static (or flip-flop based) frequency dividers, the drawback is their low locking range. The ILFD locking range is inversely proportional to the quality factor (Q) of the oscillator tank. In integrated circuit designs, this makes an ILFD sensitive to process variations. Care must be taken to ensure the tuning range of the driving circuit (for example, a voltage-controlled oscillator) must fall within the input locking range of the ILFD.

			== Digital dividers ==
			[[File:Frequency divider animation.gif\|thumb\|250px\|An animation of a frequency divider implemented with D flip-flops, counting from 0 to 7 in binary]]
			For power-of-2 integer division, a simple binary counter can be used, clocked by the input signal. The least-significant output bit alternates at 1/2 the rate of the input clock, the next bit at 1/4 the rate, the third bit at 1/8 the rate, etc. An arrangement of [[Flip-flop (electronics)\|flipflops]] are a classic method for integer-n division. Such division is frequency and phase coherent to the source over environmental variations including temperature. The easiest configuration is a series where each flip-flop is a divide-by-2. For a series of three of these, such system would be a divide-by-8. By adding additional logic gates to the chain of flip flops, other division ratios can be obtained. Integrated circuit logic families can provide a single chip solution for some common division ratios.

			Another popular circuit to divide a digital signal by an even integer multiple is a [[Johnson counter]]. This is a type of [[shift register]] network that is clocked by the input signal. The last register's complemented output is fed back to the first register's input. The output signal is derived from one or more of the register outputs. For example, a divide-by-6 divider can be constructed with a 3-register Johnson counter. The three valid values for each register are 000, 100, 110, 111, 011, and 001. This pattern repeats each time the network is clocked by the input signal. The output of each register is a f/6 square wave with 60° of phase shift between registers. Additional registers can be added to provide additional integer divisors.

			===Mixed signal division===
			(''Classification:'' ''[[Asynchronous circuit\|asynchronous]] [[sequential logic]]'')<br>
			An arrangement of [[D flip-flops]] are a classic method for integer-n division. Such division is frequency and phase coherent to the source over environmental variations including temperature. The easiest configuration is a series where each D flip-flop is a divide-by-2. For a series of three of these, such system would be a divide-by-8. More complicated configurations have been found that generate odd factors such as a divide-by-5. Standard, classic logic chips that implement this or similar frequency division functions include the 7456, 7457, 74292, and 74294. (see [[List of 7400 series integrated circuits]])

			== Fractional-n dividers ==
			{{Main\|Dual-modulus prescaler}}
			A fractional-n frequency synthesizer can be constructed using two integer dividers, a divide-by-n and a divide-by-(n + 1) frequency divider. With a modulus controller, n is toggled between the two values so that the [[voltage-controlled oscillator\|VCO]] alternates between one locked frequency and the other. The VCO stabilizes at a frequency that is the time average of the two locked frequencies. By varying the percentage of time the frequency divider spends at the two divider values, the frequency of the locked VCO can be selected with very fine granularity.

			=== Delta-sigma fractional-n synthesizers ===
			If the sequence of divide by n and divide by (n + 1) is periodic, spurious signals appear at the VCO output in addition to the desired frequency. Delta-sigma fractional-n dividers overcome this problem by randomizing the selection of n and (n + 1), while maintaining the time-averaged ratios.

			==See also==
			{{Portal\|Electronics}}
			*[[Phase-locked loop]]
			*[[Prescaler]]
			*[[Pulse-swallowing counter]] and [[pulse-swallowing divider]]

			==References==
			<references/>

			==External links==
			* [http://www.electronicproducts.com/ShowPage.asp?SECTION=3700&PRIMID=&FileName=FEBCON1.FEB2001 Delta-sigma fractional-n synthesizers]
			* [http://www.ece.uci.edu/~payam/RFD_ISCAS2005.pdf A Study of High Frequency Regenerative Frequency Dividers]

			[[Category:Electronic circuits]]

76.241.142.254: /* Plants containing other psychedelic substances */

2012-08-10T04:10:05Z

Plants containing other psychedelic substances

New page

Hi there, I am Alyson Pomerleau and I think it seems fairly great when you say it. The favorite hobby for him and his kids is fashion and he'll be starting something else alongside with it. Invoicing is what I do. Alaska is where I've always been residing.<br><br>Here is my web page; [http://www.prograd.uff.br/novo/facts-about-growing-greater-organic-garden psychic love readings]