LilSnoop40
Posts: 7
Joined: Wed Jan 16, 2013 3:02 pm

Power Supply for WiFi Dongle (Edimax) connected?

Tue Mar 04, 2014 12:34 pm

hello, I am trying to find the best power supply that will be strong enough to run a RPI with a edimax wifi dongle connected. the power supply's below are listed in order by the ones I tried first, number 3 is the one I am currently using. I have tried the brands below some work fine on one RPI but then might not work on the next, some will drop wifi connection:

(1) - AmazonBasics Wall Charger with USB Outlet (2.1 Amp Output)
http://www.amazon.com/gp/product/B005CG ... UTF8&psc=1

(2) - EasyAcc US 5V 2A Universal Travel AC Micro USB Wall Charger Adapter long cord for Tablet: Google Nexus 7,Google Nexus 10,Most Smartphone, external battery and other Micro USB Port Devices (1.6M/5.25 Feet Black)
http://www.amazon.com/gp/product/B00A9P ... UTF8&psc=1

(3) - Samsung OEM 1.0A Travel USB Wall Charger with Detachable Micro USB Data/Charge Cable - Bulk Packaging
http://www.amazon.com/gp/product/B006YC ... UTF8&psc=1

It's odd that one of the above work fine on one board then the next board that I get it will have issues like wifi drop. I see the wifi drop when its doing add-on updates. if I look at the ipad XBMC remote app the green connectivity light turns red then green back and forth. or when I select a link throughout the showing I am watching the app drops connection but the movie plays fine.

I am about to try one of these PowerGen Black 2.4-Amp (12 Watt) Dual USB Wall Charger w/flip down Plug Designed for Apple and Android Devices, its added to my amazon cart as we speak:

https://www.amazon.com/gp/buy/spc/handl ... vascript=1

Please advise, I live in the US and I don't want use a hub just looking for a reliable power supply to power the board and a wifi dongle.

Thanks

klricks
Posts: 7163
Joined: Sat Jan 12, 2013 3:01 am
Location: Grants Pass, OR, USA
Contact: Website

Re: Power Supply for WiFi Dongle (Edimax) connected?

Tue Mar 04, 2014 2:13 pm

What else is connected to the RPi?
The 5V micro USB input goes through a 'polyfuse' (F3) which limits the power through the RPi to 750mA or so. Go above that and the RPi will not be reliable. USB devices drop out. CPU hangs reboots etc.
So if an adapter gives good clean 5.00V regulation at 1A then there is no point in getting an adapter with larger mA output. Note that many cheap power supplies drop out or can't hold 5.00 volts at near the maximum load or have overstated specs on the label.
You could have other problems as well such as not turning off the WIFI power saving mode etc.

Note - nobody else can view a link of something in your shopping cart - checkout basket.
Unless specified otherwise my response is based on the latest and fully updated RPiOS Buster w/ Desktop OS.

User avatar
FLYFISH TECHNOLOGIES
Posts: 1750
Joined: Thu Oct 03, 2013 7:48 am
Location: Ljubljana, Slovenia
Contact: Website

Re: Power Supply for WiFi Dongle (Edimax) connected?

Tue Mar 04, 2014 2:22 pm

Hi,
LilSnoop40 wrote:hello, I am trying to find the best power supply that will be strong enough to run a RPI with a edimax wifi dongle connected.
Your goal might be wrong due to (also wrong) conclusion that power supply is causing the problem.

Several discussions were held in this forum mentioning RasPi internal fuse taking care for limiting the current. You should focus firstly to the question how the dongle's current can safely bypass the fuse. Two of discussions:
http://www.raspberrypi.org/forum/viewto ... 54#p501554
http://www.raspberrypi.org/forum/viewto ... 93#p496993


Best wishes, Ivan Zilic.
Running out of GPIO pins and/or need to read analog values?
Solution: http://www.flyfish-tech.com/FF32

LilSnoop40
Posts: 7
Joined: Wed Jan 16, 2013 3:02 pm

Re: Power Supply for WiFi Dongle (Edimax) connected?

Tue Mar 04, 2014 2:28 pm

Every build I make looks like this:
SanDisk Extreme 16 GB SDHC Class 10 UHS-1 Flash Memory Card 45MB/s SDSDX-016G-X46
http://www.amazon.com/gp/product/B0037F ... UTF8&psc=1

Edimax EW-7811Un 150 Mbps Wireless 11n Nano Size USB Adapter with EZmax Setup Wizard
http://www.amazon.com/gp/product/B003MT ... UTF8&psc=1

RASPBERRY PI MODEL B 756-8308 Raspberry Pi B
http://www.amazon.com/gp/product/B009SQ ... UTF8&psc=1

CY Raspberry Pi Case (Blackberry)
http://www.amazon.com/gp/product/B00ASJ ... UTF8&psc=1

Power supply any of the 3 above

The only OC settings I do look like this:
arm_freq=800 sometimes change this to 900
core_freq=400
sdram_freq=400
over_voltage=0

I add this as well, I was told this will disable the wifi from sleeping:
1.) echo "#!/bin/sh" > /storage/.config/autostart.sh && chmod +x /storage/.config/autostart.sh
2.) nano /storage/.config/autostart.sh
3.) rmmod 8192cu ; modprobe 8192cu rtw_power_mgnt=0 rtw_enusbss=0
4.) save and exit
5.) cat /storage/.config/autostart.sh (type this to see if the file you created is correct.)

Hope this is enough info.

Thanks

Return to “Troubleshooting”