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74ls04 21:50 (2006.07.31:4 research#33 tech_notes#169)

40106 application note 20:22 (2006.07.31:3 research#32 tech_notes#168)

as:

astable or monostable multivibrators

also transistor as variable resistor (obviously voltage controlled) 19:55 (2006.07.31:2 research#31 tech_notes#167)

to add further layer of switching/automation/self-immersion for new synthesiser

also as add-on modules for old neural

circuit page 38 polytronic (DDR electronics kit)

voltage control on base, emitter to ground and resistance flows across positive (of controlled signal) to collector

day one of electronics playing (one week) 17:42 (2006.07.31:1 tech_notes#166 research#30)

program as described previously

1] 555 as astable circuit producing automatic series of pulses 

a la: http://www.doctronics.co.uk/555.htm#astable

- timing portion consisting of 2 resistors and 1 ca[ (4.7 uF)

(one VR light dependent, one 680 ohms determining frequency and high
and low times of each pulse)

2] 555 also as accepting control voltage for frequency - pin 5

3] 555 as monostable trigger

4] Schmitt trigger - 2 transistors as in Polytronic book (2nd
variation with both emitters tied and potentiometer to ground.

addition of a 3rd transistor in place of one potentiometer

new ideas/work/TODO:

1] today maybe tackle RC oscillator (p162 poly) and tone generator
(p104) and compare circuits to basic electronics

2] make simple low-frequency radio circuit for connection to fences,
street furniture (along with regular transmitter)

3] print all necessary data sheets

4] plus all circuit modules as outlined.

5] hysteresis in Schmitt triggers as gap between positive and negative
going switching voltage

hysteresis:

a retardation of the effect when the forces acting upon a body are
changed (as if from viscosity or internal friction); esp: a lagging in
the values of resulting magnetization in a magnetic material (as iron)
due to a changing magnetizing force.

see:

http://www.lassp.cornell.edu/sethna/hysteresis/WhatIsHysteresis.html

and also noise in hysteresis in relation to avalanching:

http://www.lassp.cornell.edu/sethna/hysteresis/noise.html

and,

http://www.lassp.cornell.edu/sethna/hysteresis/hysteresis.html