Qi USB C Receiver for Kobo Sage?

[AudioPhool]

I found the following thread from 2020: https://www.mobileread.com/forums/sh...d.php?t=334608

No specific brand of receiver was mentioned. Since then, I was wondering if any Kobo (Sage) owners have had good luck installing a specific Qi USB Receiver?

It has been very convenient using Qi for our Galaxy phones with built-in receivers and would like to replicate same on my new Sage.

[MGlitch]

No but any receiver with a small usb plug and thin cable to the pad should work.

If you’re particularly tinkery you could ignore the thickness of the wire and just strip it, lay it flat, insulate the flat and flex them from the port along the back of the device.

But the obvious caveat there is you know what you’re doing because the farther you modify things the more they can go wrong.

[Quoth]

A 2m long USB-C cable to charge makes more sense and very cheap.

If you are expert at electronics you don't need to ask how to do this (even adding Qi charging internally with automatic connecting). If you are not expert then you buy a separate Qi power receiver which plugs into USB-C when wanted and sticks to rear (ugly and pointless).

If you are expert at electronics you might even disable Qi on things that only have it and ensure a charge cable works on an added socket (coax power or USB). No doubt there will be /are phones with Qi & BT & WiFi and no sockets at all.

[Quoth]

It's actually easy to build a Qi power receiver. A DIY one to add (ready made) is about $15 on Adafruit.

How it works:
https://www.allaboutcircuits.com/tec...less-charging/

The Wikipedia article is pretty useless.

A decent Qi Charger is harder to make.

Basically it's just an RF switching power supply with the transformer split between the charger plate and the gadget receiver. Also more limited in power than a direct connection. A Sage can charge from flat in less than 50 minutes by using about 1.5A. The add-on Qi power receivers are usually 0.5A, so x3 charging time. You need contact and reasonable alignment. As a USB-C fits in either way round and is quicker to insert I can't see the point of Qi. Of course there are Frand patents, which only possible because the USPTO is broken. The actual use is at least 60 years old and transformers with the two parts separate are maybe 150 years old, more than 120 anyway.

[AudioPhool]

Thanks for the replies. And thanks Quoth for the information and education regarding the subject.

For $11.88, I thought I would give this Qi receiver a try: https://www.amazon.com/gp/product/B0...0?ie=UTF8&th=1

[Cootey]

Originally Posted by AudioPhool

Thanks for the replies. And thanks Quoth for the information and education regarding the subject.

For $11.88, I thought I would give this Qi receiver a try: https://www.amazon.com/gp/product/B0...0?ie=UTF8&th=1

That looks handy. Please let us know how well it works for you. I’m not speaking for Quoth, but many people here are invested in their cables setup, so adding a Qi charger to a setup of cables seems redundant, but it appears you’re coming from the opposite side where you’ve already invested in a wireless charging setup and like your electronics to work around that.

I’d be interested in a charging time comparison between wired and unwired with your Sage.

[Quoth]

Originally Posted by Cootey

I’d be interested in a charging time comparison between wired and unwired with your Sage.

Depends on the the Qi adaptor bought. In theory the same speed is possible, but most deliver about 1/3rd of what the Sage can charge at, so approximately 150 minutes vs 50 minutes for a charge from flat.

No magic, just physics and mathematics. With a suitable 2A charger (not all), the Sage seems to take about 1500mA. Most slim 3rd party Qi adaptors are 500mA (but could be less). Required alignment accuracy with mat/dock will vary with charger design, not so much the receiver. It's inductive "contactless" rather than actually "radio" wireless, so a metal back damps the power and any separation or mis-alignent also drops the power.

I was also thinking that a €5 book stand and €3 cable 2m long with some modelling compound would make a dock for any ereader or tablet (obviously a particular dock would only suit one gadget with connection at side, but might suit several with socket on an end).

[DNSB]

For what it is worth, testing with a Qi charging receiver, my Sage takes ~3.5 times as long to charge compared to charging from a USB-C charging port using a USB-C/USB-C cable. The Anker wireless charger is rated at 10W but the receiver never comes close to that level even when charging a Samsung phone that should be able to handle 10W easily.

[Quoth]

Originally Posted by DNSB

For what it is worth, testing with a Qi charging receiver, my Sage takes ~3.5 times as long to charge compared to charging from a USB-C charging port using a USB-C/USB-C cable. The Anker wireless charger is rated at 10W but the receiver never comes close to that level even when charging a Samsung phone that should be able to handle 10W easily.

Thanks. I suspected at least x3 longer looking at the specs.
I use a USB-A to USB-C cable, using the 2A charger than came with my Lenovo Tablet. It charges a lot slower on the USB-C port of my Dell Lunch Box PC.

[Skydog]

I use this Anker mini-bank for my Sage OTG (or any ereader/small device). No cables, no wireless pad, no fuss. Built-in, foldable, flush USB-C fits in a small pocket. Multiple colors to match Kobo's OEM covers: