CatalinRO

Appreciate your feedback :) Regarding the code, unfortunately I have none. But I have some recommendations: just use a regular Arduino countdown timer project and start from there, I am telling you this since I tested once a 4 digits huge display using a simple Arduino Nano using code found online (it was a regular clock, pretty easy to convert it to more digits and countdown timer).

I can confirm too that removing the insulation using an aspirin works very good, only thing is not to breath in the smoke, not sure if it is toxic, but smells bad :) (I think it works because aspirin it is an acid substance - acetylsalicylic acid)

I have no experience with Dell PA-7E, but I can give you some hints to start you up. You need to open the case first, then identify the main ICs, get the data sheet and then identify on the board which components are in control / feedback of the output voltage. Be careful since you expose live high voltages !!!

It is hard to tell you now because this tutorial is pretty old and I don't remember details. Initially I experimented with some MOS-FETs in TO220 package, that was overkill but that was available around. Then I found more easy to use SMD devices (SO8 package) because they can handle the current well and also in one package were both MOS-FETs (one P and one N MOS-FETs), for me it was available IRF7309, IRF7317 (both are dual N/P MOS in SO8 package). You should chose something with Vds > 20V, Vgs >= 12V, Id >3A, (for P version, put a "-" in front of the voltages, currents) etc, it is not so critical for this application,

I am not sure. From what I remember now, I can tell you that I used a variable resistor and I played with the voltage, I wanted to see if I can get 13,8 Volt or 12 Volt, but when I was close to 15 Volt, things became unstable and the power brick stopped working on that voltage range.

Great project, you got my vote because I really understand the effort to make it and to present it to the world in such detail! I wan to emphasize something you did not stress enough :) : the beauty of the hardware you created is that the ESP8266 can be programmed with a lot of firmware and can do multiple functions besides a weather station - such module can collect data, can take decisions. When I tried in the past a similar concept (use google translate and check this out: http://catalinsimion.blogspot.com/2017/06/esp8266-outdoor-module-solar-powered-MQTT-Domoticz.html and here: http://catalinsimion.blogspot.com/2017/06/esp8266-mqtt-arduino-domoticz-home.html), I found very useful to use ESPEasy (https://www.letscontrolit.com/wiki/index.php/ESPEasy), it is an awesome firmware, pro...

Great project, you got my vote because I really understand the effort to make it and to present it to the world in such detail! I wan to emphasize something you did not stress enough :) : the beauty of the hardware you created is that the ESP8266 can be programmed with a lot of firmware and can do multiple functions besides a weather station - such module can collect data, can take decisions. When I tried in the past a similar concept (use google translate and check this out: http://catalinsimion.blogspot.com/2017/06/esp8266-outdoor-module-solar-powered-MQTT-Domoticz.html and here: http://catalinsimion.blogspot.com/2017/06/esp8266-mqtt-arduino-domoticz-home.html), I found very useful to use ESPEasy (https://www.letscontrolit.com/wiki/index.php/ESPEasy), it is an awesome firmware, providing a well structured web GUI and offering plenty of sensor support. I installed ESPEasy on Sonoff modules, on WeMos, on ESP-07 etc, all worked just fine and helping me to move faster along the project and being able to use the application instead of thinkering days, weeks, months (I used a local Domoticz deployment on a Banana Pi SBC, but accesible from Internet, but ESPEasy can be setup to send data to other web servers). Keep up the good work! :)

Thanks for the tip about the TP5100 :) As a solar charger / protection circuit for 18650 batteries, I used in the past TP4056 / DW01 modules and they worked great, the only limitation was the input voltage, therefore I used small solar panels able to provide a maximum of 6 Volt. I'll give it a try to TP5100.

Hi, do you have some detailed pics showing the marking on the 2 ICs I indicated on the red rectangles?

Hi Alain, the wall charger is designed to charge NiMH original Yaesu battery only. For the modification I made, I need an extra charger for the 18650 Lithium batteries. I charge these Lithium batteries on that charger, then I move them into the battery holder I modified and I can use the FT-60. I advise to use only protected 18650 batteries because the transceiver will drain them and may damage them.

Well done, thumb up! Try building one of these for flat-earthers :)

Maybe a silicone tube garlic peeler can help on removing the skins from the kernels (search "silicone garlic peeler" on Google). Anyway, I'll give it a try to your nutella :)

Very nice and simple, I like it. I built a similar device a while back, more complicated, I built it for a friend, still did not receive any images from his camera :) (he mentioned that the device is working fine, he has images with his dog, but no wild animal triggered it yet :) ). -> https://www.instructables.com/id/PIR-Sensor-for-DSLR-Photo-Camera/

By the way, for certain values of the variable resistor, this Dell power supply will shut down it's output and will not turn it on again unless you disconnected it from the mains (in advance you need to rotate the variable resistor to a suitable value). For sure it was designed to provide a fixed voltage with a good efficiency and maybe a modification of + / - 4 Volts can be ok, but to have a nice variable power supply, not really. But for such mods, BeachsideHank made a useful comment about using a linear regulator :) (I think there are as well Instructables on this)

Thank you for your feedback! I wanted to check for myself the formula (on this Dell power supply it is Vout = 2.5 x (R41 + R42||R42A) / (R42||R42A) ). I used values of the resistors on board (see my schematic from the Instructable) and the output voltage (19,5 Volt), I expected to calculate 2.5 Volt from the voltage divider at the VSENSE pin, since this will be compared with the internal 2.5 Volt reference. (R42 || R42A = 1996 Ohm). Voltage divider output (R41 and R42||R42A) for 19.5 Volt input is 0.556 Volt. For a certain frequency, R41 is parallel with R41A, in that situation divider output is 17,17 Volt. Not sure why.

Thank you for your feedback!

Thanks for your feedback! This effort was mostly on mechanical side, on the electronics was less effort. I think this was the reason: somewhere on the circuit I have only to replace a single resistor without considering the mechanical part of the project. This modified power supply will serve my Lithium charger only and can supply around 4 Amps max, while linear regulators can supply less current, have voltage drop on them, need extra heat sink, need a case too. I used a linear regulator for a bench power supply.

Thanks for your feedback, it may work what you are saying. You can provide the correct voltage using 5 volt USB and a regular diode and using the USB charger you should be able to give a certain amount of current. Also you need to keep an eye on a clock, divide battery capacity to the current provided by USB charger to see how much time is needed to let it charge. One I'll experiment this:)

Thanks for your feedback, I agree about lipos from ebay, you can pay a few dollars for a 6000 mAh :) I use recovered 18650 from laptop batteries. Regarding the electronics I used, that micro USB module may fail as well, but I trust it since I am using this for a while and on the other hand the voltage is lower.

Thank you for your feedback :)

Thank you for your feedback, I added an important-missing link - there is an youtube video and there you can find a good explanation on how this module work. Basically it will take care on the Lithium cell (single cell), it will charge it and will discharge it on the given specs of the Lithium.

What is the exact damage done to the board? I am not sure that I understood what is fixing your method. Initially I thought that you had an overvoltage and damaged the micro and the only way is to replace it :)