del.icio.us
We hope that our ongoing tests and semi-ramblings of the T-Mobile MDA (this may or may not apply to the Cingular 8125) signal reception and network registration issues it continues to have hasn't turned you into an anti-fan of the MDA and HTC Wizard platform. It really is an awesome device.

We continue to test this during the 30-day return period since little has been done to isolate where the weak link is:

Network -> Phone (OS or HW) -> Sim Card

The basics would indicate that under the following test conditions a conclusion can be reached...

We have two (2) MDAs with non-sequential serial numbers. This could potentially isolate the "bad batch" conclusion that is so easily drawn by the carrier's tech. support (they would immediately suggest a new SIM card and replacement device since their network tests would indicate that there are no issues on their end).

We have four (4) T-Mobile sim cards. Again, non-sequential serials.

We have one (1) Palm Treo 650 on the Cingular network.

Here's what we wanted to test:

1. Is there ANY T-Mobile signal in the room (a sometimes brown spot - not totally dark, not full strength signals)

2. Are the devices themselves defective or problematic that would require further investigation?

3. Are the Sim cards defective?

Here's our rather simple testing methodology:

1. Signal strength on both devices (unfortunately we did not have access to a Cingular 8125 on the Cingular network - this would have been a much better side-by-side). In a given spot, assuming that both devices are already registered on the network, what are their signal indicators telling us? (OK, again, a gain meter would have provided more controlled results, but...)

2. Time to Network Registration. Go from a dark spot (say an elevator within a concrete/metal building where NO ONE (not even Sprint, Nextel, Verizon) gets signal to where the signal is acquired and the phone registers.

That's it. Pretty simple. Here's what happened...

(Click on the picture for an enlarged version)


In the middle of the street in SF, CA where both phones are already registered, full strength is indicated on the signal meter of the respective devices. OK. This would indicate that T-Mobile's signal is just as strong as Cingular's in this spot.

Now, we go into the elevator and both devices drop signal immediately (as to be expected).

Immediately upon exiting the elevator into a hallway (again in this concrete/steel building), the Palm Treo 650 on the Cingular network immediately (and boy do I mean immediately!) gets two bars. The T-Mobile MDA is still searching.

We then go into a room where it's know that the MDA has spotty reception (some inbound/outbound calls have been made) but for the most part, the MDA endlessly searches. The MDA continues as expected - searching. The Cingular Treo 650 maintained its two bars from the elevator to this room. Call quality was fine with the Treo 650.

We have two more (new) MDAs coming in next week as replacements with new SIMs (this will be 6 SIMs now!). We expect the results to be the same which indicates that the problem is with the MDA on the T-Mobile network. More on this later...

Here's the update!