It took an OpenVox engineer to sort out this obscure problem in the end, but
it was pretty much as I suspected: the Quectel M20 GSM module serving span 1
was stuck in an unusual state, in which it would only operate in the 900 MHz
band. Fine for O2, Vodafone and Tesco; but no good for
Is anybody intimately familiar with the OpenVox G400P card, or the Quectel M20
RF modules fitted to it?
I am having a strange network connectivity issue with just such a card, as
follows:
The card was previously used with four O2 SIMs, and -- once I mastered
creating message PDUs! -- worked
