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    Noisy relay now dead - help ~!

    pdf is 3.3MB hmmmm here's the PSU pages though... Too small ??  :P
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    Noisy relay now dead - help ~!

    Hello, My stereo amp (NAD 317) when I turned it on started making a ratcheting up buzzer noise which would last about half a second then 'start up' (some relay would click on and all was well)...  This lasted a few days until this weekend when I was going to have a look at it but today it no...
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    Analog Filter advice required

    The square wave Its the output of an LDR, which is conditioned into the red line signal which is then scaled appropriately to be sent to various analog synthesizers ... There will be at least 10 of these sensor set ups. The idea was to keep it all analog, but maybe a bunch of sample and hold...
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    LDR offset + span adjustment

    this might be interesting reading: http://www.electronics-lab.com/forum/index.php?topic=9124.msg52348#msg52348
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    LDR offset + span adjustment

    I remember asking the same thing here years ago ... Exactly the same issue - you have an output range from A to B and you want to scale it linearly so that A is now A1 and B is B1 A1 and B1 are within reason arbitrarily related to A and B - easy to do in code (with the possible resultant...
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    Analog Filter advice required

    Hello, Question simplified: Say I had a 48Hz square wave whose high V value was modulated over time (see the black line in the first attached graphic) and I wanted to extract and output the curve of the modulation as a voltage (the red line)... How would I go about this ? Some thoughts that...
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    Freq Gen Help! - Need input in Hz instead of period...

    working now  :)  - So there is also a bit of work to do on the uP programming but I understand what is required (I'll need a 16bit I/O expander as well)  -  hmmm,  so what are all those NOR gates doing like that ?  I am yet to understand them ...
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    Freq Gen Help! - Need input in Hz instead of period...

    I'd like to check it out but clicking on the pic or the text link below it pops up a window saying: You are not allowed to access this section Is there a paid subscriber function here ? I hope I'm not being rude asking if you could post the schematic elsewhere ?  :-X thanks for your help...
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    Freq Gen Help! - Need input in Hz instead of period...

    Yep, thats definitely a start! What do you have in mind ? btw - the bottom limit off 100Hz is only because of the mechanical limits in the system thats its going to be finally impaled upon - it could go down to zero if need be, although the parts might not like that ! the odd frequencies I...
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    Freq Gen Help! - Need input in Hz instead of period...

    I was thinking yes I could enter Hz values into a uP and have a nifty LCD and telephone pad interface and let it do the math for me - but I'm still stuck with the same problem all along ...  ok at one end in terms of resolution but then it all gets out of whack a the other end of the spectrum...
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    Freq Gen Help! - Need input in Hz instead of period...

    Just read your last reply - I'm understanding the 4059 a bit more now and should note that I meant the 4017 when i referred to the 4024 in my last post ... Like I said tho I'm still stuck with dividing periods rather than working directly with Hz - I want the value entered on the thumbwheel...
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    Freq Gen Help! - Need input in Hz instead of period...

    Okidoki - I've found some BCD thumbwheels locally:  http://www.jaycar.co.nz/productView.asp?ID=SR1250&CATID=&keywords=bcd+switch&SPECIAL=&form=KEYWORD&ProdCodeOnly=&Keyword1=&Keyword2=&pageNumber=&priceMin=&priceMax=&SUBCATID= So each digit is...
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    Freq Gen Help! - Need input in Hz instead of period...

    Hi, I would like to build an device that provides a %50 cycle 0-5v square wave (easy!) - that has a range of frequencies that can be directly inputted from 100.0 Hz to 10,000.0 Hz (harder!) - I would like the 0.1 increments if possible  ... I've played around with a microcontroller called the...
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    Anti-Static Wrist Straps - use with battery powered cct's ??

    The LDR cct is nice now, especially with the LPF on the input ... I have a problem with having too many projects on the go at once - I will move onto one before completing the last...  The LDR cct has taken a back foot as it is not really required until the new year - the latest project is more...
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    Anti-Static Wrist Straps - use with battery powered cct's ??

    Hi, I have never had problems with zapping components in digital ccts and have used a fair amount of different components that came in the static sensitive device bags... The other day two components arrived in the aforementioned bags and they are worth $32US each. I thought it would be a...
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    Adjustable Voltage Reg LM317, Should it be getting this hot ?

    ok, its off to the store for me ... thanks for the answer, I would have gotten one anyway but its nice to have a heads up to the actual numbers involved - Data sheets can still read like the dead sea scrolls to me, but more and more lately the specs are starting to be meaningful - all good +...
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    Adjustable Voltage Reg LM317, Should it be getting this hot ?

    Hi, I've made the little circuit of resistors around an LM317 adjustable voltage regulator that is specified in its spec sheet (240R bet pin1 and pin2 and a 5k pot bet pin1 and gnd)... When using a 12v lead acid battery as an input and regulating the output down to to just above 7.2 volts...
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    Remote control - all i need is one bit (;

    I was also forwarded this product from the guys at the OOPic mailing group: http://www.maxstream.net/products/xbee/xbee-pro-oem-rf-module-zigbee.php and these by another : http://www.glolab.com/ the maxstream product seem much more spec'd up than the glolab product - I'll compare your site...
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    Comments welcome re. amplification/scaling and offset/bias CCT

    I suppose when you are adding op-amps to sort problems that op-amps youve already added to solve problems have themselves caused ... ..then its time to stop  :P I like the way your drawing has now color - very exciting ! Nick
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    Comments welcome re. amplification/scaling and offset/bias CCT

    the main cost in the units will be the PCB - so adding a quad op-amp IC per 1.3333 cct's wont be too much of a hassle ...  Any room for another op-amp in there  ;D ? I will breadboard this all up later tonight and see how it goes - thanks again for your help - I've got a little understanding...
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