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    resistor help

    I suspect that these are mislabeled as being 12V, and are more likely designed for 5V. They look like "regular" white LED's with a resistor in parallel buried in the heat shrink tubing. The facts that you measured 200mA at 12V, the specified current is 20mA and the resistor gets very hot...
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    Sound detector to detect hammer strikes

    Yes, vibration detectors are freely available. I just thought that it would be a simple "quick and dirty" means of testing whether monitoring sound board vibrations is a viable technique for detecting hammer strikes (assuming that you have access to a record player). Furthermore it would be...
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    Sound detector to detect hammer strikes

    Just an "off the wall" idea for sound detection - a gramophone cartridge. If you had a complete record player, just resting the tone arm on the soundboard would be an easy way to test. Pre-amp and power amp are all built in so you could simply listen to the sound or measure the output at the...
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    Sound detector to detect hammer strikes

    What about something like this? https://www.robotshop.com/ca/en/gravity-flexible-piezo-film-vibration-sensor.html?gclid=Cj0KCQiAmuHhBRD0ARIsAFWyPwiuHO2x_GGwt7isZXJ_9K3QpM-2VmHFllxbKvRZ3YYAvBxBBMipzD0aAhtDEALw_wcB
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    MCP23017 i2c IO expander data

    In line 74 you have incorrectly spelled "Interrupt". You have an extra "r".
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    08 pic acting as rc switch

    My previously posted code is probably quite simiar to that written by Alan Bond. He has even used the same technique of jumpers to select latching or non-latching operation. My design differs mainly in being 2 channel, not using an input pulse buffer and having the thresholds set in code rather...
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    08 pic acting as rc switch

    Here are the two circuits that I have used in the (distant) past.
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    SOMO-14D Embedded Audio-Sound Module

    I decided to look into the SOMO-14D Embedded Audio-Sound Module as an alternative to the ISD2560 sound recorder chip, which I have used successfully in the past for a sailboat race countdown start timer. It may also prove to be a useful unit for model sound effects, commanded by a spare RC...
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    Servo Range Extender and Failsafe

    This project takes a signal from a hobby RC radio receiver, manipulates the signal, then outputs to a servo. The user can set up the following by pressing a button on the board: Neutral position Maximum travel Minimum travel Failsafe position I use it to extend servo travel by up to 180° for use...
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    "servo" vs "pulsout"

    In the process of designing a device to increase the travel of a hobby servo, I discovered that the servo and pulsout commands do not seem to give the same position information to the servo. I would have expected the following examples to give the same result: for b2=0 to 150 pulsout 1,200...
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    Solarizing a picaxe

    How about using a Maxim 8212. Just 3 resistors to set the voltage thresholds which switch an output on and off. Just add a MOSFET for driving something. Sorry Forum, no PICAXE required, unless the 8212 output is used as a PICAXE input. See attached picture for a solar engine application.
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    Li-ion Over-discharge Protection

    I have a moderately fast single engined scale electric boat which is a bit overweight. It currently cariies two 6 x subC NiMH packs of 3500 mAh each. I am looking into replacing them with 7.2V Li-ion pack(s), but am concerned about damage due to over-discharge. Overcharging is not an issue. I...
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    PICAXE-14M pulsout error

    I am designing a rudder/throttle mixer for a 3-engined RC boat using a -14M. Input pulses are taken in for rudder and throttle on pins 1 & 2, and pulses are output on pins 1, 3 & 5 (to the 3 motor speed controllers). Pins 0, 2 and 4 drive LED indicators. I was getting wierd results on the pulse...
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    PCB's - Iron Transfer Method

    I've been making PCB's for some time using iron-on transfer from a laser print on paper. I bought some glossy paper recently in the US, and have just tried it. It works perfectly. NO imperfections, NO smearing, EASY to remove with a bit of soap and water, NO furry redidue across the bare copper...
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    Variable Speed Bipolar Stepper Motor

    My first venture into the world of stepper motors. I had no problem getting the bipolar stepper (salvaged from a printer) to work via an L293 bridge driven by a Picaxe-18. Variable speed easily achieved by a variable pause between each step (as long as the pause >4ms). I now need to control...
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    Sealed Lead-Acid Battery Charger

    I am exploring the possibility of a Picaxe controlled 12V sealed lead-acid (SLA) battery charger, so need to provide a regulated voltage to a low impedance load. The scheme suggested in a previous thread ("Driving low impedance with PWMOUT") seems to employ the power transistor (MOSFET...
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    Large Numbe Maths

    I am attempting to modify the response of an RC sevo to give a non-linear response (e.g a square law relationship between the PWM from the receiver and the PWM to the servo). I am having some difficulty within the confines of integer maths and word variable length. I understand that the actual...
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    Bench Power Supply

    I am considering building a new bench power supply (my old one has bit the dust). It strikes me that a Picaxe may be ideally suited by using ADC to monitor the DC supply and PWM (driving a MOSFET) to regulate it to a pre-set value. With a voltage divide/pot arrangement on the ADC input, this...
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