On 11/23/2016 2:24 PM, Leon Fauster wrote:> DIY based onhttp://www.pcengines.ch/ hardware ...the APU2, which is their current generation board suitable for a router like this, requires 12VDC up to 1 amp, so tis not suitable for USB power (5V, up to 2.5 amp) unless you rig up a USB to 12V DC-DC converter. I do wonder how the OP plans on connecting his phone and/or tablet via ethernet to this. if the hotel internet is wifi, and he wants his own private wifi for said phone/tablet, the router would need TWO wifi adapters. -- john r pierce, recycling bits in santa cruz
On Nov 23, 2016, at 3:40 PM, John R Pierce <pierce at hogranch.com> wrote:> > On 11/23/2016 2:24 PM, Leon Fauster wrote: >> DIY based onhttp://www.pcengines.ch/ hardware ... > > ...tis not suitable for USB power (5V, up to 2.5 amp)I think you mean 2.5 *watts* not amps. USB 2.0 and below are 500 mA @ 5 Vdc max == 2.5W. There are nonstandard extensions to USB to allow 2+ amps, but you can?t expect to get that from generic USB ports. USB 3 Type C fixes this, but I don?t think that helps the OP.> unless you rig up a USB to 12V DC-DC converter.Increasing the voltage decreases the current. TANSTAAFL. With typical conversion losses, you could only expect to get about 170 mA out of USB when boosted to 12V. Incidentally, the Raspberry Pi is only USB-powered in the sense that the base board will usually run fine from a PC USB port. Add a couple of wifi radios and an Ethernet adapter, and you may exceed the 500 mA limit. The Pi is also famously intolerant of power rail sags and such. It?s best to think of the Pi as a device that just happens to have a micro USB power connector on it, but which is still wall-powered.> I do wonder how the OP plans on connecting his phone and/or tablet via ethernet to this.It can be done: http://www.gottabemobile.com/2014/08/28/how-to-connect-an-ipad-to-ethernet/ I assume there are equivalent methods on Android.> the router would need TWO wifi adapters.Yes, that?s a much simpler option, inherent in a proper travel router, another reason to avoid hacking something up with a Pi. The problem?s already been solved, and solved well.
On 11/23/2016 3:15 PM, Warren Young wrote:> On Nov 23, 2016, at 3:40 PM, John R Pierce<pierce at hogranch.com> wrote: >> On 11/23/2016 2:24 PM, Leon Fauster wrote: >>> DIY based onhttp://www.pcengines.ch/ hardware ... >> ...tis not suitable for USB power (5V, up to 2.5 amp) > I think you mean 2.5*watts* not amps. USB 2.0 and below are 500 mA @ 5 Vdc max == 2.5W. There are nonstandard extensions to USB to allow 2+ amps, but you can?t expect to get that from generic USB ports.USB 2 battery charging extensions 1.2, from 2010, allow as much as 5 amps in charge mode, and 1.5 amps while communicating over the USB. Yes, the port (or power adapter) has to be built to allow this much power, and the device has to verify the port can provide it before it can suck it down. my 5+ year old laptop has one such 'charging' port, the other ports are limited to 0.5amp. you have to enable the charging port in the BIOS, and it can be configured to stay live when the laptop is sleeping as long as the laptop is plugged in and not running on the laptop's internal battery. http://www.usb.org/developers/docs/devclass_docs/BCv1.2_070312.zip -- john r pierce, recycling bits in santa cruz
Am 24.11.2016 um 00:15 schrieb Warren Young <warren at etr-usa.com>:> On Nov 23, 2016, at 3:40 PM, John R Pierce <pierce at hogranch.com> wrote: >> I do wonder how the OP plans on connecting his phone and/or tablet via ethernet to this. > > It can be done: > > http://www.gottabemobile.com/2014/08/28/how-to-connect-an-ipad-to-ethernet/I have such a setup here with an iPadAir. Normal network use works but "facetime" seems to be hardwired to WIFI. It complains not having a connection. So, not 100% functional. -- LF
On 11/23/2016 11:40 PM, John R Pierce wrote:> On 11/23/2016 2:24 PM, Leon Fauster wrote: >> DIY based onhttp://www.pcengines.ch/ hardware ... > > the APU2, which is their current generation board suitable for a router like this, requires 12VDC up to 1 amp, so tis not suitable for USB power (5V, up to 2.5 amp) unless you rig up a USB to 12V DC-DC converter. > > I do wonder how the OP plans on connecting his phone and/or tablet via ethernet to this. if the hotel internet is wifi, and he wants his own private wifi for said phone/tablet, the router would need TWO wifi adapters. > >You are right, I had forgotten about needing two WiFi adapters... If there is an Ethernet jack in the hotel room I would go with that but that is, of course, far from assured and two WiFi nets would be needed.