Motorola C139 V1.9.24 Won't Load from osmocom-bb

Rusty Dekema rdekema at gmail.com
Tue Apr 8 23:17:41 UTC 2014


>> Is it "official" PCS1900 support, or are you seeing some of the
>> received RF energy in the PCS band (in a very strong signal area,
>> presumably) seep through the imperfect 1800 MHz SAW filter with the
>> antenna switch set to DCS?

My apologies for the blank message which went out a moment ago; that
was a mis-click on the send button.

I have found that the PCS1900 support on this C123 is sufficient to
run the phone as a BTS using layer23/transceiver (with some code
edits). PCS1900-only handsets in the same room can connect and
exchange SMS/USSD messages when the C123 is operated in this manner.

Using layer23/mobile, the C123 sees a PCS1900 control channel. When I
try to camp on that channel, the host (PC) side of layer23/mobile
segfaults, and I have not yet attempted to debug this. But it seems
reasonable to expect that the phone would be able to camp on that cell
were it not for whatever is making it crash.

For what it's worth, on a standard PCS1900 phone, this particular
control channel in the location where I am testing shows an RSSI
somewhere between -87 and -97 dBm. On the C123 running layer23/mobile,
it is usually closer to -97 dBm, but it seems like there should be
more attenuation than that if it was passing through an imperfect 1800
MHz filter (at least, I would think).

Another thing I intend to try (if I can) is to change the C123's menu
language from Chinese to English, and then see if its built-in
software can camp on the PCS1900 cell in question.

Cheers,
Rusty D




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