usb - Delphijustin industries

DIY cable tester

Justin Roeder — Sat, 27 Aug 2022 13:36:30 +0000

In this blog I will show you two ways to make a cable tester. The 1^st way uses a arduino (software controlled). The 2^nd way uses a decade counter chip(CD4017) and a flashing LED. I am going to order the Dual RJ45 jack to screw terminals from eBay. The other connectors are from parts-express. I couldn’t find one that would tell you that it has screw terminals on parts-express. But starting from 2 dollars off of eBay you couldn’t go wrong! The screw terminals allows secure connections from other types of cords, such as USB and TV coax, whereas punchdown would not be a good choice. The reason for that is each pin on the RJ45 connector will be tied together with the usb cable, coax and rca cables. This tester will tell you which pin on one side is wired to on the other side, tells you if there’s no connection and tells you about any shorts. I ordered connectors that were attached to a cord so that soldering will be easier. It’s basically a LED chaser with two of LEDs in series one for side a and the other one for side b. You can find the arduino code on github. To use simply connect one side of the cord to side a and the other to side b

arduino circuit
4017 chip circuit

Once the parts come in a YouTube video will be uploaded

The post DIY cable tester first appeared on Delphijustin industries.

USB charger data voltages

Justin Roeder — Thu, 14 Jul 2022 20:35:10 +0000

You may be thinking that usb charging devices use just the 5v and ground wires? Well your wrong as those devices don’t want to break the charger by drawing too much current. They require certain voltages on the 2 data lines. It took me alot of research to figure out how to configure it. If you want you can try shorting the green(data+) and white(data-). This may charge at the wrong current or refuse to charge.

Here’s 3 different voltage dividers simulated in everycircuit

3 voltage dividers(you will need 2, total of 4 resistors) hook one of the data lines in the middle of each dividers

Those are configuration values used in chargers. Here’s a list of voltages.

Data+	Data-	Information
2v	2v	500mA
2v	2.7v	1000mA
2.7v	2v	2100mA
2.7v	2.7v	2400mA
1.2v	1.2v	Unknown Samsung devices

Data lines configuration

I used r1 as 60k (51k+9.1k) and r2 is 75k. For data+. For data- r1 is 75k and r2 is 49.99k resistor. I’m using a 3a 5vdc power adapter and it seems better.

The post USB charger data voltages first appeared on Delphijustin industries.

How to mount small hobby solar cells, plus a USB Solar power supply?

Justin Roeder — Thu, 24 Dec 2020 04:00:54 +0000

I looked all over the internet for a way to mount these solar cells, And only come up was ones you mount on houses. So I got a cardboard box and glue gun and tried gluing them to the piece of cardboard and it was a success! I got 19 of the 0.5v 0.8A solar cells from all electronics. They work great outside, I get around 11v. Inside there’s not enough current/voltage to run the panel meter. I got about 6v in the bathroom with it being really

All glued to the cardboard

I think for right now it doesn’t charge the phone correctly because I have the green and white wires on the USB Cord tied together. A friend told me that I need resistors on the data lines. So I looked online and came across this circuit and says it will tell the phone to draw only 500mA.

Circuit for changing

I will have to wait for the resistors to come in the mail to test it with the resistors. Down below is the pinout of the regulator I used. Just that and the 19 solar cells. Each solar cell is conneted in series(the same way batteries are connected).

The post How to mount small hobby solar cells, plus a USB Solar power supply? first appeared on Delphijustin industries.