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    Comments welcome re. amplification/scaling and offset/bias CCT

    righto - ok - thanks for the drawing.. really helpful I'll try the buffer, it'll be easy as the op-amp is a dual type, I also need to put a Low pass filter on the cct as I only need light change transistions no faster than say 200mS ... I was thinking it would be best placed on the input side...
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    DXF - problem with import into PCB, where are my nets - and what are nodes ?

    Hi, I have gone through the DXF 'getting started with PCB design' .pdf with flying colors and decided it was time to create my own cct and PCB... It was a little more complex but really nothing more in terms of using the application - at least i thought... Once I have compiled the schematic...
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    Comments welcome re. amplification/scaling and offset/bias CCT

    It is a dual-gang pot - two pots mechanically connected to provide the same (close enough) resistance as the other, they are not connected electrically.  Theese particulars ones are 'B1=B2' ... I haven't been around the electronics world long enough to encounter a different set-up... I dont...
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    Comments welcome re. amplification/scaling and offset/bias CCT

    these are linear - I checked... I was thinking maybe log would be the answer ... thanks for the reply though, always appreciated... Nick
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    Comments welcome re. amplification/scaling and offset/bias CCT

    Hi, a few months back I made this cct so I could control the output of an LDR (or phototransistor) to give me an output that would cover a 0~X Volt range (X could be anywhere from 12V down to zero). for instance if the LDR output was 2~4V volts I would minus 2 Volts with the bias single gang...
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    Remote control - all i need is one bit (;

    Hi, A project we are working on at the moment requires us the ability to have control of an operate switch on a remote piece of moving gear. Because the sight lines are so unreliable we cant use IR ... Does any one know of a radio control cct or kit that gives us one or more bits of info...
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    Flex sensor

    they were used in Nintendo power gloves ...
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    pid controller circuit

    the reason i am aware of PID control is through reading up on motor control - perhaps you could look into modifying some of the cct's and systems used in that field ? the forums at CNCzone.com have heaps of info on that... [move] :P
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    pid controller circuit

    wouldn't proportional control be enough ?  or are you introducing drag/delay/error in the system yourself ? An outline of the sensor and driven system would be helpful for anyone who wishes to help you, are you working in analog or going digital ? a lamp and LDR/phototransistor ? what are the...
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    Voltage level shifting

    Hi, I am working on a project that is using LDR's to sensor light which needs to be scaled to both 0-5v and 0-12volts with adjustable 'zero' points and scale factors depending on the ambient light mins and max's - looks like I need a similar cct... I have only worked with op amps making simple...
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    Darlington Phototransistor - can i fudge one from an NPN phototransistor ??

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    Darlington Phototransistor - can i fudge one from an NPN phototransistor ??

    Hi, I am keen to make the circuit outlined here: http://www.aaroncake.net/circuits/slave.htm it calls for a '2N5777 NPN Darlington Phototransistor' of which I am yet to find a supply of here in NZ - upon looking at the symbol used for the Darlington Phototransistor in the cct diagram in the...
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    Servos - PWM - 555 - how to get *really* low switching Hz and duty cycle

    Hi, I am trying to make a servo driving unit for time-lapse photography on an old 60's 16mm camera 8) - the servo will simply push a mechanical button but it needs adjustability that other systems wont give (like cam-follower DC motor or solenoid) - I have so far managed to get the mechanics...
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