Dollar sign being converted to question marks on new modems

[brian kusler]

Hello.

We’re transitioning from F4 modems to newer models. On both the H5 and the MultiConnect Cell 100 we’re noticing a change in character set behavior on incoming messages. Specifically the dollar sign $ character is being converted to a question mark ? at the modem level (i.e., if i send an SMS message with a dollar sign in the body, the Cell 100 receives it as a ? or blank space). We don’t observe this behavior when one of our old F4s receives the same message. We’re not noticing this with any other characters in the SMS charset. Any thoughts?

Our application allows our hardware to fall back to ASCII mode when we encounter odd carrier transcoding of SMS charsets, but because the dollar sign is in the ASCII set, this workaround is failing us.

[brian kusler]

Hello.

After much testing it seems like something happening on AT&T’s network. Their gateway is transcoding the dollar sign. If we use an M2M providers’ SIM card on the T-Mobile network, this doesn’t happen. I guess I need to take this one up with AT&T.

Hope this is helpful to someone else 🙂

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