Results from same sensor & transmitter, but 2 different receivers (with different revision numbers)

Diabetes Technology Glucose Monitoring
#1

I had mentioned in another thread that my theory for why some of us were seeing new sensors not last as long as before had to do not with the sensors themselves, but with the receivers (that have had their software updated):
http://www.tudiabetes.org/group/dexcomusers/forum/topics/a-little-unscientific-g4-research?commentId=583967%3AComment%3A3370280&groupId=583967%3AGroup%3A168831

I have been using a new sensor & transmitter with 2 different receivers (thanks to Clare, I didn't know that was possible :-) for 10 days now.
One receiver was my old one that I have had for 15 months (revision number: 2.0.1.104) and one is the new replacement receiver I got this past January (revision number: 2.0.1.158).

I got the flu yesterday so this morning I took a bath and had both receivers right next to one another and noticed this when I came out of my bath:

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Can you guess which receiver is the new one?

The receiver that didn’t miss a signal was my old one with revision number: 2.0.1.104, and the receiver below it (that missed 2 data points given the exact same broadcast signal from the same exact transmitter is my new receiver with revision number: 2.0.1.154.

Given that the receivers were right next to one another, the only other explanation that I could think of was that the receivers took their readings at different times… but this is not the case because when my sugars go low they both alert me at the exact same time (the beeps are in sync with one another) so it must be the transmitter that broadcasts every 5 minutes (rather then the receiver that accepts the signal when it decides to).

Anyway, this is obviously just one data point (or 2 points in this case :slight_smile: but it does seem very odd that 2 receivers getting the exact same signal would yield such different results.
It’s almost as if the new revision number does not trust the readings it gets from its own transmitter or something!

#2

You can find out exactly when the dexcom receiver gets the reading on the xml report. Go to the studio software. Under the patients tab click on your name, then export data. It will ask you for the date range you want to export. It exports it to your documents as an xml file which you can look at and find out exactly to the second when the receiver gets the reading. The receiver on top is the older receiver the one on the bottom is newer. But the sensor is also 2 weeks old in this picture and 3 weeks old today so it wouldn't surprise me if it dropped a few points here and there. Also both receivers gave me a false low at 2 am both said 47 and my blood sugar was 110 and 112 on separate fingersticks.

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#3

Just curious....How and why do you have 2 G4 receivers? I can see the benefit with a child - 1 with the parent and 1 with the child. Does your insurance pay for a new one every so often - or did you purchase an extra one? Aren't they warranted for 4 years or so? How does having 2 benefit you? Just curious/nosy.

(I meant to ask both of you - bort269 and Clare.)
#4

Hey Nevada, I have 2 receivers because insurance covered the second receiver after a year. They're only warrantied for 1 year.
I plugged my receiver in to my computer one day and got a message about the USB failing to connect properly and the receiver would not charge up. So I called Dexcom and they said you are out of warranty so we will send you a new one. In the meantime someone here suggested doing a "hard reset" which I did and which made the old receiver work again. So that is how I ended up with 2 that work.
The benefit for me personally is I don't have to be without the CGM data during the 2 hour calibration period. Necessary absolutely not, beneficial sure.

#5

Thanks Clare!

#6

This is interesting! Even if they read at different times, I could understand a receiver missing one reading because it read at a different time, but two is unlikely.

I'll be really interested to see whether the older receiver takes readings for more days than the new...Please keep us posted.