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Re: Lipower UVLO modification

 by Valen ¦  Sat Aug 04, 2018 4:30 pm ¦  Forum: Projects ¦  Topic: Lipower UVLO modification ¦  Replies: 2 ¦  Views: 326

One last edit the forum doesn't allow me to make anymore:
"Just unsolder R3 and fill it as a solder jumper. (or both for that matter as C2 will be useless anyway if R3 is shorted)"

Re: Lipower UVLO modification

 by Valen ¦  Sat Aug 04, 2018 4:07 pm ¦  Forum: Projects ¦  Topic: Lipower UVLO modification ¦  Replies: 2 ¦  Views: 326

Yes, R3 and C2 seem to have been rotated. But in the current configuration this is easier to mod. In the old configuration it was easier to accidentally unsolder the other components. Just unsolder R3 (or both for that matter as C2 useless anyway) and fill it as a solder jumper. Then UVLO never even...

Re: BOB-12009 - 1.5V to 5V

 by Valen ¦  Sat Aug 04, 2018 2:29 pm ¦  Forum: SparkFun Product Questions ¦  Topic: BOB-12009 - 1.5V to 5V ¦  Replies: 1 ¦  Views: 226

The mosfets on BOB-12009 has a switch-on threshold (Vgs)of around 1.3 volt for the average majority of units, worst case population has a maximum of 1.5 volt. You might get lucky that it will have lower thresholds and it works. But don't count on it. In fact, assume it fails. So yes, you have to. An...

Re: Noob question on lumenati project

 by Valen ¦  Sat Aug 04, 2018 2:16 pm ¦  Forum: Projects ¦  Topic: Noob question on lumenati project ¦  Replies: 1 ¦  Views: 321

One of those led chip takes 25 mA on it's own according to the APA102C datasheet. (Though the hookup guide mentions 60mA per unit!) Times 16 led units. At full brightness the extra load of the pro mini won't matter much. But yeah, technically you should add the pro mini board miliAmps consumption to...

The led tied to pin 13 does what you program the pin to do. So it depends entirely on how your code works. (or is misbehaving from intended)

Re: Questions on my mind.

 by Valen ¦  Sat Aug 04, 2018 1:37 pm ¦  Forum: Forum ¦  Topic: Questions on my mind. ¦  Replies: 1 ¦  Views: 1766

1: A general question deserves a general answer: Try, observe, learn. Oh, and RTFM/Datasheet. 2: Before you make changes you should know how the device works on the circuit level in the first place. Learn electronics and dissect each part of the circuit. Then work out how your change makes it behave...

Re: AD8232 ECG Board shows square waves

 by Valen ¦  Sat Aug 04, 2018 9:34 am ¦  Forum: SparkFun Product Questions ¦  Topic: AD8232 ECG Board shows square waves ¦  Replies: 6 ¦  Views: 376

Just a guess, but 5v*650/1023 = 3.2 volt. Are you sure the analog pin does not have a pull up resistor enabled in the code or physically connected? [edit: never mind, the internal pull up should get it to around 5 volt on an uno.] Or show a good and clear photo of how it is wired up. You must have m...

If the sensors are analog then it should be no problem. But are they!?! If I look at what Sparkfun has to offer then there are various temperature sensors. Please be more specific which one you intend to use. The air quality sensor ( is mostly a digital sensor...

Re: Unable to upload code from Arduino to Sparkfun 8266 Thing

 by Valen ¦  Thu Jul 05, 2018 4:24 am ¦  Forum: Projects ¦  Topic: Unable to upload code from Arduino to Sparkfun 8266 Thing ¦  Replies: 3 ¦  Views: 318

Can you program the Thing without the wires and additional boards connected? Disconnect the connections to the other boards in a systematic manner (one part at a time). Reduce complexity until it works. Then find out what was wrong before that step.

Re: Unable to upload code from Arduino to Sparkfun 8266 Thing

 by Valen ¦  Thu Jul 05, 2018 4:23 am ¦  Forum: Projects ¦  Topic: Unable to upload code from Arduino to Sparkfun 8266 Thing ¦  Replies: 3 ¦  Views: 318

p.s. Even with stick-in connector pins you can have loose wobble contacts. Soldering may not be required for breadboard but always check for loose connections. Especially with long stiff cables.

Re: Unable to upload code from Arduino to Sparkfun 8266 Thing

 by Valen ¦  Thu Jul 05, 2018 4:19 am ¦  Forum: Projects ¦  Topic: Unable to upload code from Arduino to Sparkfun 8266 Thing ¦  Replies: 3 ¦  Views: 318

Sorry, that spaghetti of wires is too hard to untangle visually. Individual pins cannot be made out. (too dark also) Please make a drawing of the 2 boards and clearly show which pins are connected by the various colored wires. Surely your MAC OS has an bitmap image editor linke MS Paint. Double chec...

Re: Battery Life/Relay advice

 by Valen ¦  Thu Jul 05, 2018 3:50 am ¦  Forum: Arduino ¦  Topic: Battery Life/Relay advice ¦  Replies: 1 ¦  Views: 2761

Sure you can use relays with 100+ volt ratings in 5 volt circuits. It should not be used in circuits that go above (or near) 100 volt. Be mindfull though that digital pins cannot supply much current. Less than the 50ma that you state. Also, they need to be protected from the inductive kickback of th...

If you supply external 3.3 volt with GND to it (EDIT: or simply 5 volt and GND to the Vusb pin and GND), and only connect to pin U0RXD, U0TXD, RTS,DTR and GND with a separate USB-to-serial converter (with 3.3volt signal levels) then it should work. The second USB-to-serial converter will likely not ...

Re: Flex sensors and Wireless Motor Shield Analog Input

 by Valen ¦  Thu Jul 05, 2018 3:18 am ¦  Forum: SparkFun Product Questions ¦  Topic: Flex sensors and Wireless Motor Shield Analog Input ¦  Replies: 2 ¦  Views: 164

The hookup guide suggests to connect the flex sensor to pin A0. This is also used as software serial receive pin on the shield for the Xbee. So there is a conflict depending the setting of the switch. Pins A2,A3,A4 might work better. Also make sure it is not defined as an output with internal pull-u...

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