Eggtimer ASL Level "jumping" on new Quantum. Thoughts?

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Tractionengines

Jack of all trades, Master of... (oh never mind)
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I have a newly assembled Eggtimer Quantum that is acting strange. I am wondering if anyone else has seen anything similar. The unit powers up, and all the screens are OK. ( Main, Setup, Testing ) I did tested the output channels with Estes Igniters, and they fired fine. I would say all is good to go.... BUT the issue I noticed was that the ASL Altitude displayed on the main screen seems to jump around with each refresh of the screen. I am used to seeing a VERY small change with each refresh of the page... but not this much.

I decided to make test of it from a cold start a few hours later. Below is data taken from the main screen over 15min period. Each time it would beep and refresh, I wrote down the ASL, Volts, and Temp...

Reading ASL Volt Temp
1 1089 7.4 72.0
2 1011 7.4 69.6
3 997 7.4 69.3
4 1016 7.4 69.8
5 1040 7.4 69.8
6 992 7.4 70.3
7 989 7.4 70.3
8 1055 7.4 70.9
9 1009 7.4 72.0
10 1025 7.4 72.2
11 1006 7.4 62.2
12 961 7.4 62.2
13 998 7.3 62.1
14 972 7.4 62.1
15 1013 7.3 61.7


Max = 1089' / Min = 961' / Difference = 128' while sitting on my desk next to the Proton.

Since the Quantum readings seemed odd. I fired up a Proton and recorded the same data. It is MUCH more stable in the ASL reading.

Reading ASL Volt Temp
1 993 7.8 64.4
2 994 7.8 68.2
3 995 7.8 70.3
4 995 7.8 72.0
5 994 7.8 63.5
6 994 7.8 64.2
7 994 7.8 64.8
8 996 7.8 65.3
9 994 7.8 66.0
10 994 7.7 66.2
11 994 7.8 68.0
12 995 7.8 68.5
13 993 7.8 68.5
14 996 7.7 69.3
15 993 7.7 69.4


Max = 996' / Min = 993' / Difference = 3' while sitting on my desk next to the Quantum.

Both of these are from "Cold Start". Not sure what to do, but I don't think I can trust the Quantum....


@cerving Any thoughts.
 
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Make sure you have it on the latest firmware. I used to have apogee detect problems in my vac chamber on older versions of the Quantum code; conclusively fixed by upgrading. Not sure if that directly relates to what you're seeing though. That last temperature reading from the Quantum is a serious anomaly too.
 
The reading on the screen is the "current" reading, not the filtered version that's used for flights. We should probably change that... due to a number of things (including the inherent sensitivity of the sensor), you can expect a little bit of variability in successive unfiltered readings.

The temperature reading may be off, the latest version of the firmware fixes that.
 
@cerving thanks for your thoughts... the variance of 138' seemed huge on the Quantum, compared to only 3' on the Proton sitting next to each other.

Is there a difference in programming between them?

I will leave the Quantum "as is" and turn off the outputs. Then send it "ride along" on some flights to log the data. If the CSV file looks good, then I'll feel better.
 
I am sure it would be a programming change, but probably only changing a pointer for what address info is displayed. Current momentary value input from sensor, versus buffered & filtered value after processing...
 
One more thing that it could be is that there was a very noisy batch of the TE MS5637 sensors shipped out last year, around the middle of the year. Most of them ended up in Quarks where it really didn't matter, but about twenty or so went into Quantums. Look at the baro sensor with a 10x jeweler's loupe... if it's stamped 02BM12322 then let me know... I'll replace the sensor at no charge.
 
OK, that's a newer one. Update the firmware and that should take care of the problem.

BTW, I just posted an update... the current Quantum version is 1.09C.
 
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The original Firmware was 1.09A. I did the update to 1.09C. , I thought I messed it up for a minute when it did continuous beep when I reconnected battery. (I forgot to remove the PGM jumper. Doesn't say to remove paperclip in instructions...)

I see that the display now shows ASL Alt. in "ft" & "m" Also, Temp in "F" & "C". Nice.

Still think I may have issues. Where does the Temp reading come from the Baro Chip, or the Wi-Fi module? I don't think the Baro Chip was any where near 100F. The only warm items were the 3.3V Regulator, and the Wi-Fi Module. Here are the readings over 5 minutes:

Time ASL ft m Temp F C
0 1087 331.3 84.8 29.3
1 1063 324.1 90.1 32.3
2 1112 338.8 93.0 33.9
3 1120 341.4 95.0 35.0
4 1122 341.9 95.3 35.2
5 1102 335.9 96.0 35.5


So ASL high-low is 59ft different, and temp was slowly rising. I am going to go over the solder joints again. maybe there is a cold joint. Then if still like this, I will build the other Quantum Kit I have here and see what it does. (This one can "ride along" on some flights for data collection, and see what that looks like.)

THANK YOU for the help Cris.
 
@cerving New issue...

After the firmware update yesterday I was going to let this one "as-is" as a fly along flight recorder only, so we could look at the data files. All was working fine. Everything was working. Channels tested etc...

Now this afternoon as soon as I power it up: I only get a single continuous beep as soon as battery is connected. I BRIEFLY hooked it to the lab power supply and its pulling ~388mA. (Yesterday it was ~75mA sitting, and ~92mA when beeping.) The 3.3V regulator gets hot in a hurry, so something is pulling there... it is holding at 3.278V.

Not sure where to start looking for the sudden high power draw ... and reason for continuous beep at power up ... any thoughts?

( The second unit is up and running, the ASL Level does jump around a bit too, but not as much. Updated firmware on that one too. )
 
Sounds like something shorted... did you have it in a sled or sitting on the table when you did the update? There are a lot of components on the bottom, so it's possible to break something if you push on the board.
 
It was sitting on some papers on my desk for the update. It worked fine after the update as I did more observations (still on my desk) of the ASL and Temp readings. (Was trying to get a feel for battery life to.) It was on for a total of 1 1/2 hours in 4 segments AFTER the update.
Then it sat (unplugged from battery) overnight, and today continuous beep when plugged in.... Just odd.

I will be out of the office till Monday. So I have the weekend to think about it. During lunch Monday I will give every joint another look, with fresh eyes...and digital magnifier

Only thing I can think of is someone knocked it on floor and put it back, but no obvious "physical damage"...
 
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Well 2 of us went over this with digital imaging & high magnification. No "shorts" or "bad" solder joints. So I am thinking that when I reflowed it for the original issue, I may have overheated something internal to the WiFi Module. When I get some time, I will pull the module off. This way I can look as the joints for the module, and clean everything.

Can the module be powered up independently with only 3.3V & Common? Should it transmit SSID at that point?
 
Sounds like something shorted... did you have it in a sled or sitting on the table when you did the update? There are a lot of components on the bottom, so it's possible to break something if you push on the board.
Cris,

Finally did some work on this board. I used our re-work station and removed the WiFi module. Then tested the Board with it removed. (Lab Power Supply @ 8.0V in, Current draw less than 1mA, 3.317V Regulator output.) Here are the voltages at each pin location. (Top view of PCB.) Does anything look off? If not the board seems OK.

PCB_Voltages.JPG



I then tested the WiFi Module independently. Lab Power Supply @ 3.300V in with only VCC and GND connected. It was drawing 328mA. I then measured Resistance of each PAD to GND. The VCC to GND Resistance of 10.27ohms would give 321mA almost exactly what we see. There is NOTHING visable on the outside of the module even with digital magnification... so I must have fried something internal to the module.

WiFi_Module_Ohms.JPG

Thoughts.... If it is only the module... Can I buy a programmed QUANTUM WiFi Module replacement from you? I want a few other kits as well.

THANK YOU.
 
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