Recent content by g6ejd

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    Another idea for wind speed and direction sensing - evaluation please!

    Thanks for doing the research chaps, as I have found all of the circuit diagrams and can now make reference to them without upsetting anyone. They are almost too trivial to post frankly, as all that's in the sensor is a single opto-slot switch. I have yet to find a picture of the disk, but for...
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    Another idea for wind speed and direction sensing - evaluation please!

    Thanks Hippy for the link to the photo of the disc. http://web.archive.org/web/20080610143200im_/http://homepages.ihug.co.nz/~chris-s/mk2_chopper_disk.JPG From which there will be 4 pulses, 3 with regular 120-deg intervals for any given speed and one pulse that is coincident with and that...
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    Absolute lowest power

    Supercapacitors are another option: where charge-hold-up time is given by T = C. (V1 – V2) / IL where T is the hold-up time, C is capacitance, V1 is the charge voltage prior to discharge, V2 is the minimum allowable voltage at the end of the discharge and IL is the load current. Using a...
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    Reading a clocked input at the right time

    FYI - 2 x 7474 and 1 NAND gate gets you a digital PLL showing phase between the two signals.
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    Simple quick question

    Well, there are a number of ways to do this, but because both switches are feeding the same point (an OR gate), you will need to connect your PICAXE to the switches themselves otherwsie you won't be able to detect which switch was activated. Assuming there is a voltage at the junction of the S1...
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    Weather Station

    I've just seen that Rev-Ed used to sell the Mexican (I think) manufactured what was the Texas Instruments weather station. It enables wind speed, direction and temperature (18B20) so really easy to link to a PICAXE for a comprehensive station. It's shame they are out of production :( They were...
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    Useful Code Examples - e.g. Bargraph, large characters on an LCD/OLED

    Hi Folks, see this link for some useful PICAXE code examples of big characters on an LCD display such as a 20x4, or a very useful bargraph : http://www.phanderson.com/lcd106/lcd107.html
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    Signal Generator

    I've done this in the past using a resistor ladder as nickab12 suggests, see attached. Surprisingly the purity of the output is not bad but the output impedance will be quite high, so would need to buffer it with say an op-amp LM355/741 etc. Mine was linked to a display and a double pole switch...
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    Parity check - 18M parts

    Has anyone figured out how to conduct a simple parity check with the 18M2 part. Easy with X2 parts becuase they have the NOB - Number Of Bits command. I have my MSF receiver getting and displaying time, but I'm trying to stop it updating a DS1307 RTC when there are reception errors. If the...
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