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    Best Solder and flux to use

    Hi, A quick question please. After 10 years of soldering i am about to run out of solder wire and flux. For the wire I have been using 60/40 Lead, 22AWG (0.7mm) wire with flux inside (Roisin? the reel doesn't say). For the the flux Ihave beenusing Roisin paste. CLeaning the board from the...
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    Recommendations for soldering station

    Hi all, I am looking for some advice please. I am on the market for a soldering station/hot air gun to solder SMD components onto my boards. What features are necessary/important for soldering and reworking small components? Any particularly good brands/models? I am looking for a tool which...
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    Tricky push button circuit - Is there a known solution?

    Hi, this is not a Picaxe question but I think it suits the forum nonetheless. It is the kind of “fundamental circuits “ question. I am trying to devise a “button pushed circuit” but I cannot figure out how to do it. I hope it is allowed. I am using a NodeMCU (a breakout board for the ESP8266)...
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    Temperature measurement in low power applications

    A sanity check please. It occurred to me that in applications where batteries need to last for a long time (years) a DS18B20 would not be a suitable sensor for temperature measurement, due to the fact that it takes quite a while to measure and transmit the temperature to the microcontroller. 12...
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    Amazing prices for prototype board manufacturing and assembly

    Hi all, I was surfing the net (as you do on a lazy bank holiday morning) and I came across this prototype board manufacturing and assembly website: https://www.pcbastore.com/ The prices for board assembly look incredibly low. If one needs to make 10-50 off something it is really not worth...
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    how to interface with a 24V pressure sensor

    Hi, I bought a pressure sensor to measure water level in a tank (1-5 metres). The sensor requires 24V DC and it modulates the current in the range 4-20mA, according to the pressure reading. In regards to how to interface it with the Picaxe I was thinking of putting the sensor in series with...
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    Harvesting power from ethernet?

    Hello, I have a project where I use NodeMCU boards to transmit temperature data in my flat to a web server through WiFi. It all works fine but, due to the high power consumption of the NodeMCU (about 150mA at 5V) I need to connect it to a power supply plugged into the mains. I am thinking...
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    USB To TTL UART stick

    Hi, I have mislaid my USB to serial TTL stick so I need to buy a new one. I have been looking at something like this: http://www.ebay.co.uk/itm/182388994594 which is similat to what I had before. What I would like though is something which has the voltage conversion (from 5 to 3v3) for the Tx...
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    How to turn a NO relay into a NC

    Hi all, I am trying to control a relay with an 08M2. The intent is to power cycle a broadband router (12V, 1A power supply) I would like to buy an off the shelf solid state relay because I haven't got time to make one and for other reasons I have no control over. Ideally I would like the relay...
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    Anyone with experience of DS-RFLoRa-2 (RF Solutions)?

    Hello, I would like to experiment with the possibilities offered by the LoRa technology for range, reliability, power consumption, etc. I am considering the module form RF solutions http://www.rfsolutions.co.uk/acatalog/FM-LORA-Transceiver-Module-pre-set-to-868MHz.html#SID=335 The reasons I...
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    Mimic a thermistor with a digital potentiometer?

    Hi, I need to find a way to digitally replicate the behaviour of a thermistor. The Project: I am working on creating a close loop control to optimise the heating system in my block of flats. The heating system has two large identical boilers controlled by a compensator (Datasheet attached)...
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    How to weatherproof an installation

    Hi everyone, Happy New Year. I am struggling to get repeatable behaviour for my project and I wonder whether it might be some dampness which causes the lack of repeatability and I might have broken the "best practice for external installations". Could someone please offer advice? Here is a...
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    Remote sensor with Solar charging and single cell LiFePo4 battery

    Hi, I have been reading several forum threads to try and understand how a remote (as for outside the house and away from mains electricity) WiFi connected temperature sensor could operate without the need to change or remove the batteries for recharging. One obvious choice would be to use a...
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    Picaxe Maths

    Hi, I am having trouble with the conversion of the calibadc10 into a decimal number to display. the code below aims to calculate two variables containing the units and two decimal points. getVoltage: calibadc10 voltUnit voltDec = Vref*50/voltUnit *2 voltUnit = Vref/voltUnit...
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    Running out of memory

    Hi, I am running out of space for the code in the 18M2 I am using for my project and I was wondering whether there are good tricks to use when coding the Picaxe to reduce the memory footprint to make more room for extra functionality. The project is nothing new for this forum, but it is for...
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    power a 3.3v circuit from 5v using a 2N7000 eMosfet?

    Hi, I have searched the forum But I haven't found an answer. I need a sanity check, as I am not confident in my limited skills. I need to control a 3v3, 200mA load (ESP8266) with a Picaxe running at 5v using 3AA batteries and to make the batteries last for days I need to turn off the 3v3 load...
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    Datalogging interrupts

    Hi there, I am doing a project to log the gas consumption in my house using a hall effect sensor switch and an AXE110 datalogger. I have sorted out the hardware side, with some help and I now have turned to the software. The idea is, rather than logging the status of the hall switch at...
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    Problem with A3213EUA-T, Hall Effect Switch

    Hi, hopefully somebody will be able to shed some light on my issue. I am trying to sense the passing of the wheel in my gas meter using a A3213EUA-T, Hall Effect sensor Switch. I have wired it up on a stripboard as for the datasheet, with cloely coupled 0.1microfarad capacitor between Vdd...
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    Hacking an angular position sensor

    Hi forum, I haven't posted a message for a while, being busy in raising my kid. At work however we have a small project we are trying to mae sense of and I tought I would ask the forum. I know how people feel about giving advice for business use. I am not asking for any time intensive input...
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    How to measure sound with Picaxe?

    Hi, I am thinking of logging the sound level from a microphone. The idea is to put a specialised chip between the microphone and the Picaxe. The chip should be able to: 1) interface with the microphone 2) apply a weighting curve (for example A weighting to get the DbA value) 3) send out the...
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