I have been using the RB411UAHR successfully with a number of Sierra Wireless MC8795v’s.
My last shipment of RB411UAHR’s are having issues in that the 3G modules will not establish a wireless connection.
I did some digging and it appears that the modules are putting themselves into low power mode because they are getting over voltage.
I’m wondering if there were any hardware changes (specifically related to the miniPCIx pinout or power) between the last batch of RB411UAHR’s that worked and this batch that is apparently having issues.
For reference, here is the one that is failing (AT command sent to the module, which is attached to the miniPCIx slot):
at!pcvolt?
Volt state: High Critical
Power supply voltage: 5160 mV (255 cnt)
And here is one that is running currently in the field:
at!pcvolt?
Volt state: Normal
Power supply voltage: 3244 mV (160 cnt)
And, I took the same module that was failing on the “new” RB411UAHR and put it on a miniPCIx to USB adapter (in other words, verifying the module is good):
at!pcvolt?
Volt state: Normal
Power supply voltage: 3204 mV (158 cnt)
I’m not sure what is responsible for regulating the 5vdc USB power down to 3vdc, but as far as I can tell, its something on these new RB411UAHR’s that was not present on previous 411 hardware.
Any thoughts or help would be greatly appreciated.