Using PAW Classic's 5v header for fan power?

[tj80]

Hi,

I have a "classic" PAW in a repurposed Stratux case which has been working well since the earliest days of PilotAware.  I recently added a second wifi dongle to use iGrid, this works very well until the unit has been running for an hour or so when the wifi connection to my tablet starts to intermittently drop.  I have isolated the cause as excessive heat (primarily generated by the RTL dongle) causing the wifi dongle to drop out, and adding a small 5v fan to the case seems to entirely solve the problem.

As I'm using a Raspberry Pi 2 which does not have built-in wifi I do not have any spare USB ports to power the fan.  I've been testing with a separate cable running to the second USB port on my powerbank, but notice there are unpopulated pads on the classic PAW board JP2 header marked 5v and GND which appear to route directly to the GPIO pins on the Pi.  The fan only draws 60mA (though presumably has a slightly higher draw at start-up) - would I be OK to power it from these unused pads on the PAW board?

Many thanks,
Tim

[exfirepro]

Hi Tim,

I have certainly run a fan in one of my development Rosettas in the past - when testing dual RTL SDRs for multi-band reception, but that was in pre-iGrid days so only had the on-board WiFi to consider. In your case you have (as you state) two WiFi dongles to power as well. In my case, the fan was powered directly from the 5volt-out points at the USB end of the PAW Bridge board. There would certainly be no problem in giving it a try - you just need to keep an eye out for any sign of under-voltage errors appearing on the PAW Home Screen (or on the Radar Screen if you habitually use that).

i would be very interested in hearing whether that definitely has an effect on your WiFi connectivity.

Best Regards

Peter